Particle tracking serves as a computational technique for determining the mean field of dynamically tracked charged macroparticles of a particle beam within an accelerator. Conventional solver tend to neglect collisionality, resulting in loss of relevant information (particle and momentum redistribution). In this study, macro-particle collisions are incorporated into a 3D Poisson solver. In...
With the development of the steady state micro bunching (SSMB) storage ring, its parameters reveal that the ultra relativistic assumption which is wildly used is not valid for the electron beam bunch train, which has length in the 100 nm range, spacing of 1 μm and energy in hundreds MeV range. The strength of the interaction between such bunches and the potential instability may need careful...
As one of the state-of-the-art radiotherapy approaches, proton therapy possesses conformal dose profiles yet expensive cost. Designing a facility with a small footprint and a high treatment efficiency is the main goal for researchers to fulfill the potential of proton therapy and make it more affordable both for vendors and patients. In this contribution, the design of a light-weight proton...
SSRF (Shanghai Synchrotron Radiation Facili-ty)/SXFEL (Shanghai Soft X-ray FEL) Facility has de-veloped an advanced variable polarization transverse deflecting structure TTDS (two-mode transverse deflect-ing structure) to perform variable polarization based on the design of a dual-mode RF structure. The 15-cell prototype of the TTDS was fabricated at SSRF/SXFEL. Because the two modes operate...
The Round to Flat Beam Transformation (RFBT) is one of the emittance exchange techniques that can improve the Luminosity for the future accelerator project International Linear collider (ILC). RFBT experiment can be conducted in the KEK-STF, and the expected performance is 334 in emittance ratio. In December 2023, we performed a pilot experiment at STF to optimize the injector conditions. To...
The Beam Coupling Impedance (BCI) is a crucial aspect in the realm of accelerator physics, as it describes the electromagnetic interactions between charged particle beams and the accelerator structure. The measurement and quantification of BCI is an essential requirement to assess and mitigate its impact, particularly when introducing new components or addressing problems within existing...
This study explores various neural network approaches for simulating beam dynamics, with a particular focus on non-linear space charge effects. We introduce a convolutional encoder-decoder architecture that incorporates skip connections to predict transversal electric fields. The model demonstrates robust performance, achieving a root mean squared error (RMSE) of $0.5\%$ within just a few...
An accurate physics simulation model is key to accelerator operation because all beam control and optimization algorithms require good understanding of the accelerator and its elements. For the AGS Booster, discrepancies between the real physical system and online simulation model have been a long-standing issue. Due to the lack of a reliable model, the current practice of beam control relies...
Steady-state microbunching (SSMB) represents an innovative scheme for generating high-power coherent radiation. This approach is expected to generate kilowatt-scale extreme ultraviolet (EUV) radiation for lithography in the semiconductor industry. During the second phase of the SSMB proof-of-principle experiment (SSMB PoP II), the creation of quasi-steady-state microbunches requires specific...
Strong field Terahertz (THz) light source has been in-creasingly important for many scientific frontiers, while it is still a challenge to obtain THz radiation with high pulse energy at wide-tunable frequency. In this paper, we introduce an accelerator-based strong filed THz light source to obtain coherent THz radiation with high pulse energy and tunable frequency and X-ray pulse at the same...
An ion cloud confined in a Paul trap eventually reaches a Coulomb crystalline state when strongly cooled toward absolute zero. The normalized emittance of the Coulomb crystal can be in the sub-femtometer range. The trap is thus usable as a unique ion source for nano-beam production, though the available beam intensity is limited. This new concept was first discussed nearly 20 years ago* and...
This study examines Laser Engineered Surface Structures (LESS) in the context of their potential application within particle accelerators. These structures are investigated due to their efficient reduction of secondary electron yield to counteract the formation of electron clouds, a phenomenon detrimental to accelerator performance. A critical aspect of their evaluation involves understanding...
In the SuperKEKB/Belle-II experiment, a multitude of elementary particle reactions is initiated through the collision of 4 GeV positrons with 7 GeV electrons, paving the way for the exploration of new physics. The experiment includes plans for the substantial enhancement of luminosity in the future, aiming to achieve an integrated luminosity approximately 100 times the current level. However,...
In this paper, we delve into the application and comparative analysis of the Accelerator Physics Emulation System Cavity-Beam Interaction (APES_CBI) module within the BEPC-II (Beijing Electron-Positron Collider) experiments. We developed the APES_CBI module as an advanced time-domain solver, specifically designed to analyze RLC circuits driven by beam and generator currents and to simulate the...
A novel tuning approach, Model Coupled Accelerator Tuning (MCAT), has been applied to the separated function DTL at TRIUMF's Isotope Separator and Accelerator (ISAC). A digital twin of the rare-isotope postaccelerator is used for transverse and longitudinal tune optimizations, which are then loaded directly into the control system. Beam-based testing produced accelerated beam with a 0.26%...
At the Facility for Advanced Accelerator Experimental Tests (FACET-II) accelerator, a pair of 10 GeV high-current electron beams is used to investigate Plasma Wakefield Acceleration (PWFA) in plasmas of different lengths. While PWFA has achieved astonishingly high accelerating gradients of tens of GeV/m, matching the electron beam into the plasma wake is necessary to achieve a beam quality...
The automation upgrade of the photoinjector for the Compact X-Ray Light Source (CXLS) at Arizona State University is described. As the accelerator vault of the CXLS is only 10 meters long, the photoinjector drive laser is located in an enclosure inside the vault. Since ionizing radiation is present in this room during operations, it necessitates remote control of all devices used to optimize...
Super-NaNu is a proposed neutrino experiment as part of the SHADOWS proposal for the high intensity facility ECN3 in CERN's North Area. It aims to detect neutrino interactions downstream of a beam-dump that is penetrated with a 400 GeV high intensity proton beam from the SPS. The experiment would run in parallel to the HIKE and SHADOWS experiments, taking data with an emulsion detector....
We present a novel method for minimizing the effects of radiative depolarization in electron storage rings by use of vertical orbit bumps in the arcs. Electron polarization is directly characterized by the RMS of the so-called spin orbit coupling function in the bends. In the Electron Storage Ring (ESR) of the Electron-Ion Collider (EIC), as was the case in HERA, this function is excited by...
High Power Targetry (HPT) R&D is critical in the context of increasing beam intensity and energy for next generation accelerators. Many target concepts and novel materials are being developed and tested for their ability to withstand extreme beam environments; the HPT R&D Group at Fermilab is developing an electrospun nanofiber material for this purpose.
The performance of these nanofiber...
This work examines the multi-pass steering of six electron beams in an FFA arc ranging from approximately 10.5 GeV to 22 GeV. Shown here is an algorithm based on singular value decomposition (SVD) to successfully steer all six beams through the arc given precise knowledge of all beam positions at each of one hundred and one diagnostic locations with one hundred individual corrector magnets:...
We are developing a compact synchrotron light source using laser electron acceleration, focusing on creating a tabletop accelerator-based radiation system. Our approach involves a small ring-type dipole with block-shaped permanent magnets, prioritizing cost and weight reduction. Simple beam dynamic calculations revealed that a smaller electron beam divergence angle results in a more stable...
The paper introduces design and optimization of a high-repetition-rate infrared terahertz free-electron laser (IR-THz FEL) facility, which leverages optical resonator-based FEL technology to achieve a higher mean power output by increasing pulse frequency. Electron beam of the facility will be generated from a photocathode RF gun injector and further accelerated with a superconducting linear...
A beam position monitor based on Cherenkov diffraction radiation (ChDR) is being investigated as a way to disentangle the signals generated by the electromagnetic fields of a short-pulse electron bunch from a long proton bunch co-propagating in the AWAKE plasma acceleration experiment at CERN. These ChDR BPMs have undergone renewed testing under a variety of beam conditions with proton and...
Beam tomography is a method to reconstruct the higher dimensional beam from its lower dimensional projections. Previous methods to reconstruct the beam required large computer memory for high resolution; others needed differential simulations, and others did not consider beam elements' coupling. This work develops a 4D reconstruction using Markov Chain Monte Carlo.
The linear acceleration part of the SHINE project consists of two 3rd harmonic cryogenic modules which are operating at 3.9 GHz. Each of the cryomodules consists of eight 3.9 GHz 9-cell superconducting cavities. The SHINE specifications of the 3.9 GHz cavities are Qo >2.0e+9@13.1 MV/m and maximum accelerating gradient >15 MV/m. The 3.9 GHz cavities were treated with buffered chemical polishing...
Recent experimental measurements in the Large Hadron Collider (LHC) have shown a clear correlation between beam-beam resonance driving terms and beam losses, with a characteristic bunch-by-bunch signature. This observation creates interesting conditions to study diffusive processes. Over the past few decades, early chaos indicators, frequency map analysis and dynamic aperture studies have been...
We performed an optimisation study of a C-band photoinjector for high-charge electron beams. Such a device is capable of producing high brightness electron beams, with low energy spread and small transverse emittance, which are properties required by Inverse Compton Scattering radiation sources and compact light sources in general. This work aimed to carry out, via numerical simulations,...
FEL oscillators typically employ a two-mirror cavity with spherical mirrors. For storage ring FELs, a long, nearly concentric FEL cavity is utilized to achieve a reasonably small Rayleigh range, optimizing the FEL gain. A challenge for the Duke storage ring, with a 53.73 m long cavity, is the characterization of FEL mirrors with a long radius of curvature (ROC). The Duke FEL serves as the...
A large challenge with Plasma Wakefield Acceleration lies in creating a plasma with a profile and length that properly match the electron beam. Using a laser-ionized plasma source provides control in creating an appropriate plasma density ramp. Additionally, using a laser-ionized plasma allows for an accelerator to run at a higher repetition rate. At the Facility for Advanced Accelerator...
Photocathodes at Negative Electron Affinity (NEA), like GaAs and GaN, allow for efficient production of spin-polarized electrons. When activated to NEA with cesium and an oxidant, they are characterized by an extreme sensitivity to chemical poisoning, resulting in a short operational lifetime. In this work, we demonstrate that deposition of a cesium iodide (CsI) layer can be used to enhance...
A Compact Transverse Deflecting System (Compact-TDS) designed for longitudinal electron bunch diagnostics in the femtosecond regime is presently undergoing commissioning at the Karlsruhe Institute of Technology (KIT). This technique, based on THz streaking using a resonator structure, demands a high level of electron beam controllability and stability at the micrometer scale. To meet these...
The ongoing Plasma-driven Attosecond X-ray source experiment (PAX) at FACET-II aims to produce coherent soft X-ray pulses of attosecond duration using a Plasma Wakefield Accelerator [1]. These kinds of X-ray pulses can be used to study chemical processes where attosecond-scale electron motion is important. For this first stage of the experiment, PAX plans to demonstrate that <100 nm bunch...
This work presents the design of a compact high-efficiency terahertz source, a collaborative effort between UCLA and RadiaBeam Technologies. The system, driven by a thermionic RF gun, features prebunching elements including alpha-magnet and electromagnetic chicane to effectively compress the long beam generated from the gun. By sending such beam into tapering enhanced waveguide oscillator, we...
This paper explores the phenomenon of asymmetric blowout in plasma wakefield acceleration (PWFA), where the transversely asymmetric beam creates a transversely asymmetric blowout cavity in plasma. This deviation from the traditional axisymmetric models leads to unique focusing effects in the transverse plane and accelerating gradient depending on the transverse coordinates. We extend our...
As part of the Snowmass'21 planning exercise, the Advanced Accelerator Concepts community proposed developing multi-TeV linear colliders and considered beam-beam effects for these machines [1]. Such colliders operate under a high disruption regime with an enormous number of electron-positron pairs produced from QED effects. Thus, it requires a self-consistent treatment of the fields produced...
Meaningful prediction and enhancement of spin-polarization in the RHIC/EIC accelerator complex relies on accurate modeling of each sub-component. Here we describe a symplectic field approximations of both Siberian Snakes in the AGS, enabling practical long-term tracking calculations. Without such symplectic representations, particle motion destabilizes very quickly close to injection energy....
An electron beam degrader is under development with the objective of measuring the transverse and longitudinal acceptance of the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab. This project is in support of the CE+BAF positron capability. Computational simulations of beam-target interactions and particle tracking were performed integrating the GEANT4 and Elegant...
This paper details the implementation and benchmarking of crystal collimation within MERLIN++ accelerator physics library and demonstrates its application in simulating crystal collimation process for the High Luminosity(HL) upgrade of Large Hadron Collider(LHC) at CERN. Crystal collimation is one of the key technologies suggested to enhance the current collimation system according to the...
In vivo studies support that the combination of protons and spatial fractionation, the so-called proton minibeam radiotherapy (pMBT), enhances the protection of normal tissue for a given tumor dose. A preclinical pMBT facility for small animal irradiation at the 68 MeV cyclotron of Helmholtz-Zentrum Berlin (HZB) will improve the understanding of this method. A two-step energy-degrading system...
The Compact X-ray Light Source (CXLS) requires the acceleration of electron bunches to relativistic energies, which collide with focused IR laser pulses to produce X-rays which are then transported to the experiment hutch. A class 4 UV laser is used at the photocathode to liberate the electrons that are generated via the photoelectric effect. During electron acceleration bremsstrahlung...
In addition to the desired electron beam, RF photoinjectors such as the one in LCLS-II produce dark current via field emission. Left unchecked, the dark current can cause various operational issues in the accelerator, such as increased radiation, damage to accelerator components and diagnostics, and desorption of gases from vacuum chamber surfaces. In this contribution, we present measurements...
The coherent THz facility developed at NSRRC delivers superradiant radiation with wavelengths ranging from 100 – 500 um from a gap tuneable U100 planar undulator. An S-band laser-driven photocathode rf gun has been used in its 25 MeV linac system to generate a sub-picosecond high brightness relativistic electron beam via velocity bunching for emission of coherent THz radiations. However, the...
The attainable acceleration gradient in normal conducting RF accelerating structure is limited by RF breakdown, a major challenge in high gradient operation. Some of the recent experiments at the Argonne Wakefield Accelerator (AWA) facility suggest the possibility of breakdown mitigation by using short RF pulses (on the order of a few nanoseconds) to drive the accelerating structures. To...
To generate the very high brightness beams in light sources, injectors based on radiofrequency photo-guns with very high peak electric fields on the cathode are used. However, this very high surface electric field on the surface of a radio frequency cavity leads to the generation of dark current due to the field emission effect which can damage the instrumentation and radio-activate...
The performance of superconducting radiofrequency (SRF) cavities is critical to enabling the next generation of efficient, high-energy particle accelerators. Recent developments have focused on altering the surface impurity profile through in-situ baking, furnace baking, and doping to introduce and diffuse beneficial impurities such as nitrogen, oxygen, and carbon. However, the precise role...
We present measurements of enhanced quantum efficiency (QE) in thin film photocathodes due to optical interference in the cathode-substrate multilayer. Modulations in the quantum efficiency of Cs$_{3}$Sb films grown on multilayer 3C-SiC substrates are observed over a range of visible wavelengths, and are shown to increase the QE by more than a factor of two at certain wavelengths. We derive a...
Bunch length is an important parameter for free-electron laser (FEL). The deflecting RF cavity was used in the beam length diagnostic instrument. In this paper, we present the design of a 3-cell rectangular deflecting RF cavity for a compact terahertz (THz) free-electron laser (FEL) facility. The 3-cell deflecting cavity has a residual orbit offset of zero as compared to single-cell deflecting...
As compared to conventional travelling-wave (TW) structures, parallel-coupled accelerating structures eliminate the requirement for the coupling between cells, providing greater flexibility in optimizing the shape of cells. Each cell is independently fed by a periodic feeding network for this structure. In this case, it has a significantly short filling time which allows for ultrashort pulse...
Capable of achieving a high repetition rate with strong focusing, Fixed Field Alternating gradient (FFA) accelerators have the potential to be used for pulsed high intensity operations. With no pulsed high intensity FFA ever built so far, a prototype machine called FETS-FFA has been proposed to study the FFA option for the next generation spallation neutron source (ISIS-II). One of the...
In the field of structure wakefield acceleration there is considerable interest in radiofrequency (RF) structures capable of producing high gradients. Structures in the sub-terahertz (sub-THz) regime are of note due to their high gradient and high efficiency, allowing for a low physical footprint. In the pursuit of this goal we have designed a metallic corrugated W-band structure using the CST...
Coherent synchrotron radiation (CSR) in linear accelerators (linacs) is detrimental to applications that require highly compressed beams, such as FELs and wakefield accelerators. However, traditional measurement techniques lack the precision to fully comprehend the intricate multi-dimensional aspects of CSR, particularly the varying rotation of transverse phase space slices along the...
Minimizing the energy spread within the electron bunch is essential for an optimal performance of free electron lasers. Wakefields from corrugated and dielectric structures have been demonstrated to be effective in bunch dechirping. However, the repercussions in beam quality are not yet well understood. Here, a dielectric wakefield structure, manufactured to be included at the CLARA facility,...
Stationary CT is a novel CT technology to significantly improve scanning speed, by using distributed multiple ray sources instead of conventional helical rotation with single source. This work presents an S-band multi-beam accelerator as a multiple MV-level X-ray source for industrial stationary CT application. This accelerator consists of 7 parallel-distributed acceleration cavity and 6...
Negative Electron Affinity (NEA) activated GaAs photocathodes are the only one capable of generating spin-polarized electron beam larger than 90%. However, the NEA layer currently made from mainstream cesium (Cs) and oxygen (O) is chemically unstable, the NEA-GaAs photocathode has a rapid QE degradation over time or electron beam. As a result, it requires an operating vacuum pressure of 1e-9...
Radiotherapy is an effective, non-invasive, widely used treatment for cancerous tumours that uses x-ray photon, electron and ion beam sources. The Laser-hybrid Accelerator for Radiobiological Applications (LhARA) is a novel laser-driven accelerator system under development that aims to prove the principle of the laser-driven approach to Particle Beam Therapy (PBT). This study aims at the...
A surface treatment device has been established at the Wuxi Platform, enabling chemical polishing treatment on coupon samples. Currently, several samples treated with buffered chemical polishing (BCP) have been utilized in the investigation of nitrogen doping and medium-temperature baking mechanisms. This paper presents the development process of this device along with the experimental...
Many mature methods to measure the betatron function of a lattice rely on beam position monitor (BPM) data and the model of the whole machine. In this study, specific sections of the Relativistic Heavy Ion Collider (RHIC) were analyzed, taking advantage of BPMs separated by drift spaces near interaction points (IPs) and B3/B4 magnet sections of RHIC. This (local) approach would provide a...
One of the Grand Challenges in beam physics is development of virtual particle accelerators for beam prediction. Virtual accelerators rely on efficient and effective methodologies grounded in theory, simulation, and experiment. We will address one sample methodology, extending the understanding and the control of deleterious effects, for example, emittance growth. We employ the application of...
The Rapid Cycling Synchrotron (RCS) of the Electron Ion Collider (EIC) will be used to accelerate polarized electrons from 400 MeV to a top energy of 5, 10, or 18 GeV before injecting into the Electron Storage Ring. At 1 GeV, the RCS will perform a merge of two bunches into one, adding longitudinal dynamics that effects the dynamic aperture, depending on the merge parameters. In this paper,...
Crab crossings are designed to increase the luminosity of accelerators by ensuring beam interactions are closer to a head on collision. One will be implemented at the Electron Ion Collider (EIC) at Brookhaven National Laboratory. It is then important to examine how the crab cavity will affect beam dynamics at the EIC. Methods such as Frequency Map Analysis (FMA) have been shown to be helpful...
The use of glassy carbon (GC) as a future nuclear waste storage material depends on its capability to retain all radioactive fission products found in spent nuclear fuels. Ruthenium (Ru) is one of the most important fission products in nuclear reactors. This work investigates the effects of implantation temperature and annealing on the structural evolution and migration of Ru implanted in GC....
DAΦNE is a a medium energy electron-positron collider operating in the National Laboratory of INFN at Frascati, Italy. The accelerator complex consists of two rings with an approximate circumference of 97 m. High-intensity electron and positron beams circulate and collide with the center of mass energy of around 1.02 GeV. The FCCee is an ongoing lepton collider project and its current injector...
The experience gained at CERN by the R&D for LINAC4 has been exported to medical and societal applications. With an innovative design of the Radio Frequecy Quadrupole (RFQ) at high frequencies, it is possible to build very com- pact structures, reproducible in industry and with the po- tential of full portability. ELISA (Experimental LInac for Surface Analysis) is a linear proton accelerator...
In the context of the HL-LHC upgrade, RF Crab Cavities (CCs) are one of the key components. Due to the increased intensity, the collider will operate with a large crossing angle scheme and these CCs will be used to counteract the geometrical reduction factor coming from the crossing angle. Amplitude and phase noise injected from the Low-Level RF, are known to induce transverse bunch emittance...
CERN Proton Synchrotron (PS) is featured with 100 C-shaped combined-function Main Units (MUs) magnets with a complicated pole shape. The operation and the modelling of the PS-MUs has been historically carried out with empirical beam-based studies. However, it would be interesting to understand whether, starting from a proper magnetic model and using the predicted harmonics as input to optics...
The Future Circular Collider (FCC) study foresees the construction of a 90.6 km underground ring where, as a first stage, a high-luminosity electron-positron collider (FCC-ee) is envisaged, operating at beam energies from 45.6 GeV (Z pole) to 182.5 GeV (ttbar). In the FCC-ee experimental interaction regions, various physical processes give rise to particle showers that can be detrimental to...
As the China Spallation Neutron Source (CSNS) Phase II project upgrades beam power to 500 kW, maintaining horizontal beam orbit stability necessitates more precise output current from the main magnet power supplies. The existing control strategy, suited for 100 kW extraction power, falls short of the higher precision requirements for the output current, characterized by a quasi-sinusoidal...
THz-frequency accelerating structures could provide the accelerating gradients needed for compact next generation particle accelerators. One of the most promising THz generation techniques for accelerator applications is optical rectification in lithium niobate using the tilted pulse front method. However, accelerator applications are limited by losses during transport and coupling of THz...
The present ion physics program in the CERN accelerator complex is mainly based on Pb ion beams. The ALICE3 detector upgrade proposal at the Large Hadron Collider (LHC) requests significantly higher integrated nucleon-nucleon luminosity compared to the present Pb beams, which can potentially be achieved with lighter ion species. These lighter ion species have also been requested by the...
Plasma wakefield acceleration is nowadays very attractive in terms of accelerating gradient, able to overcome conventional accelerators by orders of magnitude. However, this poses very demanding requirements on the accelerator stability to avoid large instabilities on the final beam energy. In this study we analyze the correlation between the driver-witness distance jitter (due to the RF...
To reduce the dark current and secondary electron multiplication in conventional conducting accelerator cavities, and to improve the quantum efficiency of copper photocathodes, thereby achieving higher beam quality and enhancing the acceleration gradient and operational stability of accelerators, Tsinghua University designed a 13.56 MHz internal coil-type capacitive discharge plasma...
Dielectric-lined waveguides have been extensively studied for high-gradient acceleration in beam-driven dielectric wakefield acceleration (DWFA) and for beam manipulations, including the application of zero transverse force modes in the waveguides. In this paper, we investigate the zero transverse force modes excited by a relativistic electron bunch passing through a dielectric waveguide with...
A minimally-invasive gas jet in-vivo dosimeter for medical treatment facilities is being developed at the Cockcroft Institute (UK), to provide full online (real time) monitoring with less frequent calibration. The monitor functions via a thin, low-density, gas jet curtain, intersecting with the beam. Online monitoring is crucial for hadron beams where acceptable dose tolerances are narrow,...
Field emission (FE) and vacuum arcs limit the maximum achievable accelerating field of both normal and superconducting cavities. The performance of accelerating cavities can be improved after a long conditioning process. Understanding this process and the formation of vacuum arcs is important for all technologies where vacuum arcs cause device failure. The understanding could be more complete...
In order to miniaturize ion injectors for particle therapy, a design of ion injectors based on a 325 MHz operating frequency was completed. The LINAC was consist of a 2.0 m length RFQ and a 3.8 m length IH-DTL, which was designed to accelerate 12C4+, 3H+, 3He+ and 18O6+ beams to 7 MeV/u. The RFQ cavity and the first DTL tank was been manufactured using aluminum. This paper gives an overview of...
The occurrence of breakdown events are a primary limiting factor for future accelerator applications aiming to operate under high field-gradient environments. Experimental evidence often leads to a hypothesis that breakdown events are associated with temperature and dark current spikes on the surface of RF devices. In the past decade, there has been increased interest in unveiling the...
Fourth-generation synchrotron radiation sources, which are currently being planned in several accelerator laboratories, require fast orbit feedback systems to correct distortions in the particle orbit in order to meet stringent stability requirements. Such feedback systems feature corrector magnets powered at frequencies up to the kilohertz range, giving rise to strong eddy currents. To...
The Future Circular Electron-Positron Collider (FCC-ee) represents a cutting-edge particle physics facility designed to further investigate the Z, W± and Higgs boson in addition to the top quark. The implementation of Nested Magnets (NMs) in the FCC-ee arc cells would maintain high luminosity and reduce its energy consumption. The use of these special magnets induces changes in the damping...
Radio Frequency Knock Out (RF-KO) resonant slow extraction is commissioned at the Cooler Synchrotron (COSY) Jülich for the first time to extract the stored beam and deliver spills with constant particle rates to the experiments. Therefore, transverse RF excitation generated with a software-defined radio is applied to control the extraction rate. A built-in feedback system adjusts the...
Particle beams with asymmetric transverse emittances and profiles have been utilized in facilities for driving wakefields in dielectric waveguides and to drive plasma wakefields in plasma. The asymmetric plasma structures created by the beam produce focusing forces that are transversely asymmetric. We utilize the ellipticity of the plasma ion cavity to model the beam evolution of the flat beam driver.
By using a high-energy electron beam (beam energy of several hundred MeV) strongly focused on the tumor lesion area, radiotherapy can be performed with a relatively simple beam generation and handling system while resulting in a suitable shape of the deposition energy curve in a tissue-like material. Quadrupole magnets are typically used for beam focusing, which makes the beam delivery system...
Laser-field emission, or optical field emission, is a process that can produce electron beams with high charge density and high brightness with ultrafast response times. Using an extended nanostructure, such as a nanoblade, permits plasmonic field enhancement up to 80 V/nm with an incident ultrafast laser of wavelength 800 nm. Stronger ionizing fields lead to higher current densities, so...
A non-invasive bidirectional beam profile monitor using beam-induced fluorescence upon a thin sheet of gas has been developed at the Cockcroft Institute in collaboration with CERN and GSI. This device is particularly suited to the Electron Beam Test Stand, and as such, a bespoke gas injection has been optimized for this specific use-case to provide diagnostics unavailable to conventional...
As an important experimental tool, the Optical Frequency Combs (OFCs) has had a profound impact on research in various fields, whereas, generating high power high repetition frequency OFCs at tunable frequencies is still a limitation for most of the existing methods. In this study, free-electron laser (FEL) is proposed to generate coherent X-ray OFC with a tunable repetition frequency and...
Obtaining ultrashort electron bunches is the key to the studies of ultrafast science, yet second and higher order nonlinearities limits the bunch length to a few femtoseconds after compression. Traditional regulation methods using rf higher order harmonics have already optimized the bunch length to sub-fs scale, yet the energy loss and rf jitter are not negligible. In this paper we demonstrate...
Generating layers of symmetrical optical caustic beams using a specific configuration of cylindrical lenses is an innovative idea with potential application in precision alignment and other fields. The technique allows the generation of layers of non-diffracting beams with opposite accelerating directions. This approach can be extended in two dimensions or to create rotationally symmetric...
The CERN Accelerator Beam Transfer group has recently launched a study to investigate the life cycles of pulsed septum magnets. The development is aiming to enhance the prediction of anomalies, leading to reduced life cycles of these beam transfer equipment. For this reason, the standard vacuum operated, direct drive septa magnet has been chosen to investigate critical design features. In the...
Future electron accelerator applications such as x-ray free electron lasers and ultrafast electron diffraction are dependent on significantly increasing beam brightness. We have designed and produced a new CrYogenic Brightness-Optimized Radiofrequency Gun (CYBORG) for use in a new beamline at UCLA to study the brightness improvements achievable in this novel low temperature high gradient...
LCLS-II-HE is an energy upgrade of the LCLS-II linac from 4 GeV to 8 GeV. The X-ray FEL photon energy (Self-Amplified Spontaneous Emission mode) will extend towards 12 keV (from the present 5 keV) based on the current beam emittance. To reach higher photon energy range towards 20 keV, a new injector with a much brighter electron beam will be required. Here we study an X-ray regenerative...
Schottky monitors serve as non-invasive tools for beam diagnostics, providing insights into crucial bunch characteristics such as tune, chromaticity, bunch profile, or synchrotron frequency distribution. However, octupole magnets commonly used in circular storage rings to mitigate instabilities through the Landau damping mechanism, can significantly affect the Schottky spectrum. Due to the...
In the upcoming compact STorage ring for Accelerator Research and Technology (cSTART), LPA-like electron bunches are only stored for about 100 ms, in which the equilibrium emittance will not be reached. Therefore, to measure parameters such as bunch profiles, arrival times and bunch current losses, bunch-resolved diagnostics are needed.
The booster synchrotron of the KARA accelerator accepts...
SIRIUS is a 4th generation synchrotron light source built and operated by the Brazilian Synchrotron Light Laboratory (LNLS). Recently, investigations of noise sources and the storage ring RF plant identification enabled a fine-tuning of the Digital Low-Level Radio Frequency (DLLRF) parameters. This paper presents the main improvements implemented, which include the mitigation of 60Hz noise...
The institute of applied physics (IAP), university of Frankfurt, has been working for years on the development of increasingly powerful 4-Rod RFQ accelerators for hadron acceleration. The need for such accelerators has increased significantly in the recent past, as accelerator-driven neutron sources are becoming increasingly important following the closure of various test reactors. High beam...
Using hollow plasma channels is one approach to compact positron acceleration, potentially reducing the cost and footprint of future linear colliders. However, it is prone to transverse instabilities since beams misaligned from the channel axis tend to get deflected into the channel boundary. In contrast, asymmetric electron drive beams can tolerate misalignment and propagate stably after the...
Within the context of a design study of a LINAC for ionization cooling, this paper presents the result of incorporating a scattering model in RF-Track (v2.1) for charged particles heavier than electrons. This inclusion enables simulations for applications like ionization cooling channels for muon colliders. Within RF-Track, a novel semi-Gaussian mixture model has been introduced to describe...
Digital Tomosynthesis (DT) is a 3D mode of x-ray imaging. Adaptix Ltd have developed a novel mobile DT device enabled by implementing an array of R-ray emission points and a flat-panel detector. This device gives access to human and animal 3D imaging, as well as to non-destructive material evaluation. DT is not as clinically popular as Computed Tomography (CT) or radiography, and flat-panel...
One of the significant sources of residual losses in superconducting radio-frequency cavities is magnetic flux trapped during the cool-down due to the incomplete Messier effect. If the trapped vortices are non-uniformly distributed on the cavity surface, the temperature mapping revealed the “hotspots” at the location of high density of pinned vortices. Here, we performed a rf test on 1.3 GHz...
A muon collider allows one to have a high energy reach for physics studies while having a relatively compact footprint. Ideally such a machine would accelerate muon beams to about 5 TeV. We present a preliminary lattice design for a pulsed synchrotron that will accelerate muon beams to their maximum collision energy and having a circumference of 16.5 km, which would allow it to fit just within...
In 2023, about 2 months of the LHC operation were devoted to the Heavy Ions physics, after more than 5 years since the last ion run. In this paper, the results of the 2023 Ion optics commissioning are reported. Local corrections in Interaction Point (IP) 1 and 5 were reused from the regular proton commissioning, but the optics measurement showed the need for new local corrections in IP2. We...
SLAC's LCLS-II is rapidly advancing towards MHz repetition rate attosecond X-ray pulses, opening new opportunities to leverage the abundance of data in combination with advances in machine learning (ML) to better align the x-ray source with specific experimental goals. We approach the challenge from both ends of the facility. Starting at the X-ray output, we showcase our low latency, high...
The luminosity of particle colliders depends, among other parameters, on the transverse profiles of the colliding beams. At the LHC at CERN, heavy-tailed transverse beam distributions are typically observed in routine operation. The luminosity is usually modelled with the assumption that the 𝑥-𝑦 planes are independent (i.e. statistically uncorrelated particle distributions between the planes)...
Compact synchrotrons, such as those proposed for cancer therapy, use short and highly bent dipoles. Large curvature drives non-linear effects in both body and fringe fields, which may be critical to control to obtain the desired dynamic aperture. Similarly to current practice, for straight magnet, our long-term goal is to aim at finding a parametrization of the field map that requires few...
Skeleton cyclotron is a compact size air-cored cyclotron with a high temperature superconducting (HTS) coil system. HTS coils’ high critical current density and high heat stability allow magnetic field induction without using any iron core. With this advantage, the magnetic field configuration can be adjusted quickly without consideration for the hysteresis from iron. The purpose of skeleton...
In the framework of the acceleration techniques, the Plasma Wake Field Acceleration (PWFA) is one of the most promising in terms of high machine compactness. For this purpose, a crucial role is played by the particle beam focusing upward and downward the plasma-beam interaction, performed by high gradient Permanent Magnet Quadrupoles (PMQs). In the framework of the INFN-LNF SPARC_LAB (Sources...
Development of an optical fiber-based beam loss monitor (OBLM) is in progress at the Cockcroft Institute (CI), UK. The novel sensor utilizes the Cherenkov radiation (CR) emitted in optical fibers by relativistic particle showers generated in beam loss or breakdown events.
Breakdowns are a problem for high-power magnetrons, such as those in medical accelerator facilities, as damage to the...
SLAC’s LCLS-II-HE upgrade will expand the energy regime of their XFEL at high repetition rates. Due to the low emittance requirement, a superconducting QWR based electron gun was proposed by SLAC and is being developed by FRIB in collaboration with ANL and HZDR. The emittance compensation solenoid consists of two main coils, along with horizontal and vertical dipoles as well as normal and skew...
Ongoing studies at the Spallation Neutron Source (SNS) Beam Test Facility (BTF) seek to understand and model bunch dynamics in a high-power LINAC front-end. The BTF has recently been upgraded with a reconfiguration from a U-shaped line to a Straight line. We report the current state of model benchmarking, with a focus on RMS beam sizes within the FODO line. The beam measurement is obtained...
Nonlinear focusing elements can enhance the stability of particle beams in high-energy colliders through Landau Damping, by means of the tune spread which is introduced. Here we discuss an experiment at Fermilab's Integrable Optics Test Accelerator (IOTA) which investigates the influence of nonlinear focusing elements, such as octupoles, on the beam’s transverse stability. In this experiment,...
Beam profile measurements in the LHC and its injector complex show heavy tails in both transverse planes. From standard profile measurements, it is not possible to determine
if the underlying phase space distribution is statistically independent. A measurement campaign in the CERN PSB was carried out to introduce cross-plane dependence in bunched beams in controlled conditions, in view of...
We report updates on design work* and ongoing development of a fluorescence-based molecular gas curtain which will be used to observe the 2D transverse profile of multi-charge state heavy ion beams at the Facility for Rare Isotope Beams (FRIB). The device will produce an ultra-thin, rarefied nitrogen gas sheet and requires that the gas curtain be uniform and thin to prevent distortion of the...
This paper describes the mechanical design of the Future Circular Collider e+e- interaction region. The Future Circular Collider, as a forefront particle accelerator project, demands meticulous attention to the mechanical integrity and performance of its components, to the integration of the different systems and to the respect of the spatial constraint. The vacuum chamber design, the support...
The SRF community has shown that introducing certain impurities into high-purity niobium can improve quality factors and accelerating gradients. We question why some impurities improve RF performance while others hinder it. The purpose of this study is to characterize the impurities of niobium coupons with a low residual resistance ratio (RRR) and correlate these impurities with the RF...
Space charge has been a limiting effect for low energy accelerators inducing emittance growth and tune spread. Tune shift and tune spread parameters are important for avoiding resonances, which limits intensity of the beam. Circular modes are round beams with intrinsic flatness that are generated through strong coupling, where intrinsic flatness can be transformed to real plane flatness...
Linear particle accelerators are elaborate machines that demand a thorough comprehension of their beam physics interactions to enhance performance. Traditionally, physics simulations model the physics interactions inside a machine but they are computationally intensive. A novel solution to the long runtimes of physics simulations is replacing the intensive computations with a machine learning...
GaAs-based photocathodes activated to negative electron affinity (NEA) is the only existing technology that can deliver intense and highly spin-polarized electron beams for the forthcoming Electron-Ion Collider as well as enable spin-polarized scanning tunneling microscopy, ultrafast spin-polarized low-energy electron diffraction, and other cutting-edge experiments. The degree of...
We present the design and initial characterization of a multi-mode cavity, a novel electromagnetic structure with potential benefits such as compactness, efficiency, and cost reduction. The 2nd Harmonic mode was chosen to linearize the fundamental mode for use as an accelerating and bunching cavity. The reduction in the number of cavities required to bunch and accelerate promises cost and...
A Dielectric Disk Accelerator (DDA) is a metallic accelerating structure loaded with dielectric disks to increase its shunt impedance. These structures use short RF pulses of 9 ns to achieve accelerating gradients of more than 100 MV/m. Single cell and multicell clamped structures have been designed and high power tested at the Argonne Wakefield Accelerator. During testing, the single cell...
Requirements for the noise in electron beams (NEB) have recently approached the Shot-noise level in some new applications. The density fluctuations of intense beams in the near-infrared (NIR) region are being measured at the Fermilab Accelerator Science and Technology (FAST) facility. The main goal of the experiment is to accurately compare the Shot-noise model with the observations of optical...
Numerical optimizations on couplers of the traveling wave accelerating structures usually require lots of calculation resources. This paper proposes a new technique for matching couplers to an accelerating structure in a more efficient way. It combines conventional Kroll method with improved Kyhl method, thereby simplifying the tuning and simulation process. We will present the detailed design...
The alignment installation work of Hefei Advanced Light Facility (HALF) is usually carried out in tunnels. We convert the coordinates of the landmark points to the global coordinate system through coordinate transformation, and accurately adjust them to the corresponding coordinate values for alignment and installation. However, tunnels are often long and narrow, which can easily lead to...
The research is focused on finding new ways to generate high-intensity, monochromatic X and gamma-rays, surpassing the capabilities of existing methods. While Free-Electron Lasers (FEL) have limitations on photon energy, and Inverse Compton Scattering relies on powerful lasers, the search for alternatives continues. TECHNO-CLS, a PATHFINDER project funded by the European Innovation Council, is...
Bulk niobium is currently the standard material for constructing superconducting radio frequency (SRF) cavities for acceleration in particle accelerators. However, bulk niobium is limited, and new materials and surface treatments may allow greater performance to be reached. We present progress on novel materials and treatments for SRF cavity fabrication.
The Shanghai Light Source has been operated since 2009 to provide synchrotron radiation to 40 beamlines of the electron storage ring at a fixed electron energy of 3.5 GeV. The Shanghai Laser Electron Gamma Source (SLEGS) is approved to produce energy-tunable gamma rays in the inverse Compton slant-scattering of 100 W CO2 laser on the 3.5 GeV electrons as well as in the back-scattering. SLEGS...
The beam transverse emittances play a critical role in high-energy colliders. Various measurement techniques are employed to measure them. In particular, the so-called luminosity emittance scans (or Van der Meer scans) are used in order to evaluate the convoluted beam emittances. This method assumes different emittances in the two planes but identical emittances in the two beams. In this...
Low energy electron bunches experience emittance growth due to space charge. This effect can lead to large emittances which are unacceptable for a facility like PERLE at IJCLab. PERLE will be an ERL test facility circulating a high current electron beam. The traditional method to reduce emittance due to this effect is already planned for the PERLE injector, this has a limit of how small the...
The Electron-Ion Collider (EIC) Hadron Storage Ring (HSR) will use strong hadron cooling to maintain the beam brightness and high luminosity during long collision experiments. An Energy Recovery Linac is used to deliver the high-current high-brightness electron beam for cooling. For the best cooling effect, the electron beam requires low emittance, small energy spread, and uniform longitudinal...
ELSA LINCS (ELSA Linac INverse Compton Source) at CEA DAM DIF is an Inverse Compton Scattering X-ray source in the 5-40 keV range, through interaction between 10-30 MeV electrons with a Nd:YAG laser. The source was upgraded to increase the X-ray flux produced in the 5-40 keV range. The new experimental setup and imaging systems have been modified for compatibility with fundamental emission at...
Laser-plasma accelerators (LPAs) can have high acceleration gradients on the order of 100 GeV/m. The high acceleration gradients of LPAs offer the possibility of powering future colliders at the TeV range and reducing the size of particle accelerators at present energy levels. LPAs need tightly focused, high intensity laser pulses and require guiding structures to maintain the laser focus over...
Nanostructures are currently attracting attention as a medium for obtaining ultra-high-density plasmas for beam-driven or laser-driven acceleration. This study investigates Bayesian optimization in Laser Wakefield Acceleration (LWFA) to enhance solid-state plasma parameters towards achieving extremely high gradients on the order of TV/m or beyond, specifically focusing on nanostructured...
The Future Circular electron-positron Collider, FCC-ee, is a design study for a 90 km circumference luminosity-frontier and highest-energy e+e- collider. It foresees four operation modes optimized for producing different particles by colliding high-brightness lepton beams. Operating such a machine presents unique challenges, including stored beam energies up to 17.5 MJ, a value about two...
Ultrafast electron diffraction (UED) is a growing accelerator application that enables the study of transient material processes at sub-picosecond timescales with nanometer spatial resolution. In this proceeding, we present simulations of the Cryogenic Brightness-Optimized Radiofrequency Gun (CYBORG) beamline using the General Particle Tracer (GPT) code that are optimized for the application...
The cathode test stand at LANL is utilized to test velvet emitters over pulse durations of up to 2.5 µs. Diode voltages range from 120 kV to 275 kV and extracted currents exceed 25 A and depend on cathode size and pulse duration. Current density measurements taken with scintillators or Cherenkov emitters produce inconsistent patterns that disagree with the anticipated beam profile. Several...
For the Recycler Ring at Fermilab, space charge tune shifts of almost 0.1 will have to be dealt with under the Proton Improvement Plan (PIP-II) framework. This will lead to the excitation of third order resonances. The minimization of Resonance Driving Terms (RDTs) allows to mitigate the harmful effect of these betatron resonances. Past work has shown that previously-installed sextupoles can...
This study primarily investigates the parameters and processes involved in depositing Nb thin films on copper cavities under DC and HIPIMS modes. For this purpose, a high-power magnetron sputtering system was designed, conducting a total of 36 experiments. Improvement and optimization of parameters such as duty cycle (under HIPIMS mode), peak current, and bias voltage were undertaken to...
The study investigates the radiation attenuation performance of five ternary glass systems with varying chemical compositions: 50P$_2$O$_5$-(50-x)BaO-xEu$_2$O$_3$, where x = 0, 1, 2, 4, and 6 mol%. It utilizes theoretical and Monte Carlo methods to determine shielding parameters such as attenuation coefficients, mean free path, value layers, electron densities, conductivity and neutron...
Generating beam with nC-level charge is of great significance for particle colliders. In order to achieve lower emittance and length of bunch, based on the photocathode injector, we designed a L-band gun and L-band accelerating tube. However, with many coupled parameters, it is difficult to optimize its performance to the limit when optimizing them separately. Therefore, we employed a...
In this work we demonstrate the generation of a record low root mean square normalized transverse electron emittance of less than 30 pm-rad from a flat metal photocathode – more than an order of magnitude lower than the best the emittance that has been achieved from a flat photocathode. This was achieved by using plasmonic focusing of light to a sub-diffraction regime using plasmonic...
Fermilab is currently engaged in the development of an 800 MeV superconducting RF linac, aiming to replace its existing 400 MeV normal conducting linac. PIP-II is a warm front-end producing 2 mA of 2.1 MeV H-, followed by a sequence of superconducting RF cryomodules leading to 800 MeV. To mitigate potential damage to the superconducting RF cavities, PIP-II uses laser-based monitors for beam...
With very small beam sizes at IP (several tens of nanometers in the vertical direction) and the presence of strong FFS quadrupoles in the CEPC, the luminosity is very sensitive to the mechanical vibrations, requiring excellent control over the two colliding beams to ensure an optimum geometrical overlap between them and thereby maximize the luminosity. Fast luminosity measurements and an IP...
Ultrafast high-energy pulsed electron beams can provide deep penetration and variable linear energy transfers by controlling the characteristics of the electron bunch, both of which currently oversubscribed heavy ion facilities cannot provide. Early experiments at the UCLA PEGASUS beamline (~3 MeV) with ~1 ps electron bunches and a 50 μm spot size yielded charge collection transients that were...
The longitudinal compression of intense proton bunches with strong space-charge force is an essential component of a proton-based muon source for a muon collider. This paper discusses a proton-bunch compression experiment at the Integrable Optics Test Accelerator (IOTA) storage ring at Fermilab to explore optimal radio frequency (RF) cavity and lattice configurations. IOTA is a compact...
For certain photonuclear experiments utilizing Compton gamma-ray beams, beam-uncorrelated background poses a significant challenge. At the High Intensity Gamma-ray Source (HIGS), we have developed methods to generate pulsed free-electron laser (FEL) beams by transversely or longitudinally modulating the storage ring FEL. Both methods enable periods of FEL interaction: one by transversely...
At the CERN Large Hadron Collider (LHC), bent crystals play a crucial role in efficiently redirecting beam halo particles toward secondary collimators used for absorption. This innovative crystal collimation method leverages millimeter-sized crystals to achieve deflection equivalent to a magnetic field of hundreds of Tesla, significantly enhancing the machine’s cleaning performance...
Ultra-low-charge operation of free-electron lasers down to 1 pC or even lower, requires adequate diagnostics for both, the users and the operators. For the electro-optical bunch-arrival time monitor (BAM) a fundamental design update is necessary to yield single-digit fs precision with such low charges. In 2023 a vacuum sealed demonstrator for a novel pickup structure with integrated...
Research on a novel permanent quadrpole magnet (PQM) design is introduced in this paper. It can make the quadrupole magnetic field gradient continuously adjustable by modulating several permanent magnet blocks. Four poles of the magnet inform an integral whole to ensure good structural symmetry, which is essential to obtain high-quality quadrupole magnetic field permanent quadrupole magnet....
The utilization of laser modulation techniques shows potential in producing sub-femtosecond electron beams within photoinjector electron guns. The precise spatial alignment between the modulated laser and electron beam is crucial for the stable emission of sub-femtosecond electron beams. In practical applications, inevitable lateral positional fluctuations are present in both the modulated...
Pulse compressors have been widely used to generate very high peak RF power in exchange for the reduction in the RF pulse length for linear accelerators. As compared to a traditional SLAC Energy Doubler(SLED), a spherical pulse compressor is more compact while maintaining a high energy gain. A C-band spherical pulse compressor is studied in this paper, which consists of a dual-mode polarized...
Ionization cooling stands as the only cooling technique capable of efficiently reducing the phase space of a muon beam within a short time frame. The optimal cooling parameters of a muon collider aim to minimize transverse emittance while simultaneously limiting longitudinal emittance growth, resulting in optimal luminosities within the collider ring. This study shows that achieving efficient...
Diamond Light Source (DLS) is a 3 GeV synchrotron facility in the UK, which has been a part of the Cherenkov diffraction radiation (ChDR) collaboration since 2017 and is now in its second phase of experiments. The current experiment aims to produce and test a one-dimensional beam position monitor (BPM) that utilizes ChDR at visible and near-infrared (NIR) wavelengths. This paper will cover the...
Muon colliders hold promise for high luminosity multi-TeV collisions, without synchrotron radiation challenges. However, this involves investigation into novel methods of muon production, acceleration, cooling, storage, and detection. Thus, a cooling demonstrator has been proposed to investigate 6D muon ionization cooling. The MICE experiment validated ionization cooling to reduce transverse...
Laser wakefield accelerators (LWFAs) are capable of supporting accelerating and focusing forces on the order of 10–100 GeV/m, about three orders of magnitude greater than conventional RF accelerators. While theoretical solutions for the electromagnetic (EM) focusing fields have been developed, the field structures have yet to be verified experimentally. In this poster, we present simulation...
The beam loading effect results in a gradient reduction of the accelerating structures due to the excitation of the fundamental mode when the beam travels through the cavity. A recent implementation of this process in the tracking code RF-Track allows the simulation of realistic scenarios, thus revealing the impact of this phenomenon in start-to-end accelerator designs. In this paper, we...
In the injector section of electron linacs, both internal space charge forces and wakefield effects influence the beam dynamics. So far, existing simulation approaches can not account for both effects simultaneously. To fill this gap, we have developed a computational method to account for both effects self-consistently*. It couples a space charge solver in the rest frame of the bunch with a...
The CXFEL project at ASU will produce coherent soft x-ray radiation at a university-scale facility. Unlike conventional XFELs, the CXFEL will use an optical undulator in addition to nanobunching the electron beam instead of a static magnetic undulator. This reduces the undulator period from cm-scale to micron scale and lowers the requirements on the electron beam energy. CXFEL’s overtaking...
Moving towards beam energies around 2-6 MeV in ultrafast electron diffraction (UED) experiments allows achievement of larger coherence length for better k-space resolution, while the temporal resolution is improved when shorter electron bunches are generated and the velocity mismatch between the optical pump and UED probe is reduced.
At Helmholtz-Zentrum Dresden-Rossendorf (HZDR), a series...
The proof-of-principle (PoP) experiment at the Super Proton Synchrotron (SPS) at CERN aims at demonstrating laser cooling of high energy Li-like Pb79+ in a synchrotron. First laser cooling simulations with realistic laser and beam parameters of the Gamma Factory proof-of-principle experiment (PoP) in the Super Proton Synchrotron (SPS) at CERN are presented. Furthermore, we investigate the...
On-axis injection mode is planned to use in the Southern Advanced Photon Source (SAPS), which requires high quality to injection pulsed power supply. Gyromagnetic nonlinear transmission line (GNLTL) is introduced as a pulse compressor to meet the needs for pulse width. In this paper, 3-D finite element model is established based on Landau-Lifshitz-Gilbert equation and Maxwell’s equations. The...
The Karlsruhe Research Accelerator (KARA) is an electron storage ring for accelerator research and the synchrotron of the KIT light source at the Karlsruhe Institute of Technology (KIT). KARA features an electro-optical (EO) in-vacuum bunch profile monitor to measure the longitudinal bunch profile in single shot on a turn-by-turn basis using electro-optical spectral decoding (EOSD). A...
High quality electron bunch trains enable investigations in scientific frontiers with high resolution and efficiency and are earnestly desired by various accelerator facilities, including inverse Compton scattering (ICS), high energy computed tomography, and free electron lasers. An average beam flux can be greatly increased by using the bunch train mode. A bunch train with an average current...
A cavity-based x-ray free-electron laser (CBXFEL) is a possible future direction in the development of fully coherent hard x-ray sources of high spectral brilliance, a narrow spectral bandwidth of ~1-100 meV, and a high repetition rate of ~1 MHz. A diagnostic tool is required to measure CBXFEL spectra with a meV resolution on the shot-to-shot bases. Here we present test results of a single...
A pair spectrometer, designed to capture single-shot gamma spectra over a range extending from 10 MeV through 10 GeV, is being developed at UCLA for installation at SLAC’s FACET-II facility. Gammas are converted to electrons and positions via pair production in a beryllium target and are then subsequently magnetically analyzed. These charged particles are then recorded in an array of quartz...
Recent studies have investigated a longitudinal instability that may develop in electron storage rings featuring higher-harmonic cavities. The instability, also referred to as periodic transient beam loading (PTBL), manifests as a slow oscillation of bunch longitudinal profiles following a coupled-bunch mode 1 pattern. In this contribution, we applied a well-established theory of longitudinal...
In this study, we present a deep learning-based pipeline for predicting superconducting radio-frequency (SRF) cavity faults in the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab. We leverage pre-fault RF signals from C100-type cavities and employ deep learning to predict faults in advance of their onset. We train a binary classifier model to distinguish between stable...
During the operation of the Continuous Electron Beam Accelerator Facility (CEBAF), one or more unstable superconducting radio-frequency (SRF) cavities often cause beam loss trips while the unstable cavities themselves do not necessarily trip off. The present RF controls for the legacy cavities report at only 1 Hz, which is too slow to detect fast transient instabilities during these trip...
Iron-dominated superconducting magnets are one of the most popular and used design choices for superconducting magnetic quadrupoles for accelerator systems. While the iron yoke and pole tips are economic and effective in shaping the field, the large amount of iron also leads to certain drawbacks, namely, unwanted harmonics from the sextupole correctors nested inside of quadrupole iron pole...
The space-charge neutralization of an ion beam by created electrons when the beam ionizes the gas is investigated using a three-dimensional electrostatic particle-in-cell code. Different kinds of injected gases are considered, and their space-charge compensation transient times are compared. The created secondary electrons by the beam collision with neutral gas along the beam trajectories are...
In order to enhance the accelerating gradient of accelerators, cryogenic accelerating structures have been investigated. Based on material characteristics and technical conditions, a fundamental design has been accomplished. Photonic band-gap (PBG) structures employ a lattice of rods to impede the propagation of RF field through the lattice at specific frequencies while effectively damping...
To achieve very high luminosity, the next generation circular colliders adopt the crab waist collision scheme with a large Piwinski angle. In this scheme, beams collide with high current, low emittances, and small beta functions at the interaction point (IP). However, several effects arising from these extreme parameters, especially the coherent X-Z instability, will significantly impact the...
A new infrared Free-Electron Laser (FEL) facility FELiChEM has been established as an experimental facility at the University of Science and Technology of China. It consists of two free electron laser oscillators which produce mid-infrared and far-infrared lasers covering the spectral range of 2-200 μm at the present stage. The output power is a crucial parameter for users, and it is usually...
Manipulation electron beam phase space technology by laser-electron interaction has been widely used in accelerator-based light sources. The energy of the electron beam can be modulated effectively under resonant conditions by using an intense external laser beam incident into the undulator together with the electron beam.
Enhancing the modulation efficiency is crucial for the performance of...
The Mainz Energy-Recovering Superconducting Accelerator (MESA), an energy-recovering (ER) LINAC, is currently under construction at the Institute for Nuclear physics at the Johannes Gutenberg-Universität Mainz, Germany. In the ER mode continues wave (CW) beam is accelerated from 5 MeV up to 105 MeV. The energy gain of the beam is provided through 2 enhanced ELBE-type cryomodules containing two...
The importance of shaping temporal profiles in accelerator physics is highlighted by a wide range of applications, such as plasma acceleration and improved performance in free electron laser applications. In our study, we focus on controlling the dispersion in a bunch compressor and the energy chirp of the beam entering the compressor to achieve diverse temporal profiles. The transmission of...
Metamaterial accelerators driven by nanosecond-long RF pulses show promise to mitigate RF breakdown. Recent high-power tests at the Argonne Wakefield Accelerator (AWA) with an X-band metamaterial structure have demonstrated to achieve a gradient of 190 MV/m, while we also observed a new acceleration regime, the breakdown-insensitive acceleration regime (BIAR), where the RF breakdown may not...
Recent advancements in electron beam compression methods have enabled the production of ultrashort electron beams at the sub-femtosecond scale, significantly expanding their applications. However, the temporal resolution of these beams is primarily limited by the flight time jitter, especially during their generation in photocathode RF electron guns. In this paper, to mitigate the impact of...
Beam Plasma Interactions Experiment (Beam-PIE) is a NASA sounding rocket experiment that successfully ran in November 2023. Beam-PIE used space as a laboratory to explore wave generation from a modulated electron beam in the ionosphere. Beam-PIE electron accelerator used a 10keV electron gun and a 5-GHz RF cavity, enabling the acceleration of the electron beam to a total energy of ~25–60 keV....
The proton Electric Dipole Moment (pEDM) storage ring to measure the electric dipole moment of the proton [1] is proposed to be built in the tunnel of the Alternating Gradient Synchrotron (AGS) at Brookhaven National Laboratory (BNL) by storage ring EDM (srEDM) Collaboration. We proposed that the AGS Booster to pEDM ring transfer and injection line (BtP) would use the partial portions of the...
High-brightness photoinjectors generate low emittance, ultrashort electron beams that are capable of tracking dynamical states of matter with atomic-scale spatio-temporal resolutions via ultrafast electron scattering, as well as providing precisely-shaped electron beams for advanced acceleration research and large-scale facilities such as free-electron laser and inverse Compton scattering. In...
SLEGS is a Laser Compton Scattering gamma source. The gamma energy is 0.66 to 21.7 MeV, and the gamma flux is approximately 4.8e+5 to 1.5e+7 phs/s. Gamma activation method is used in beam flux monitor, medical isotpoe production and nuclear astrophysics in SLEGS*. Gamma beam flux under different collimated apertures has been checked by gamma activation method by using various half-life nuclide...
The thermal diffusion and acoustic properties of Nb impacts the thermal management of devices incorporating Nb thin films such as superconducting radiofrequency (SRF) cavities and superconducting high-speed electronic devices. The diffusion and acoustic properties of 200-800 nm thick Nb films deposited on Cu substrates were investigated using time-domain thermoreflectance (TDTR). The films...
The precision of the proton therapy beam depends on maintaining high field quality in the magnet’s good field region. Iron yoke is employed in magnets to increase the magnetic field and reduce the fringe field. However, when providing a high magnetic field for transporting relatively high-energy particles, the saturation effect of the yoke can distort the field quality. To mitigate this...
The performance and scientific reach of advanced electron accelerator applications, such as particle colliders, x-ray free electron lasers, and ultrafast electron diffraction, are determined by beam brightness. The beam brightness is constrained by the quality of photocathodes and is associated with low Mean Transverse Energy (MTE) of photoemitted electrons. To meet the requirements for...
Beam lengthening is an effective and commonly used method to improving the beamlife of storage rings. Based on the previously proposed design of a room temperature conducting bimodal RF cavity. we conducted relevant dynamic simulations. Tracking study on a simulated storage ring lattice with the beam energy of 2 GeV and the synchronous radiation energy of 357 KeV, the results show that, the...
The Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab operates hundreds of superconducting radio frequency (SRF) cavities in its two linear accelerators (linacs). Field emission (FE) is an ongoing operational challenge in higher gradient SRF cavities. FE generates high levels of neutron and gamma radiation leading to damaged accelerator hardware and a radiation hazard...
Laser-driven ion accelerators (LDIAs) are well-suited for radiobiological research on ultra-high dose rate effects due to their high intensity. For this application, a transport system is required to deliver the desired beam intensity and dose distribution while online dosimetry is required due to the inherent shot-to-shot variability of LDIAs. At the BELLA Center's iP2 beamline, we...
This study focuses on the beam source for the LCLS-II-HE Low Emittance Injector (LEI) design: a state-of-the-art superconducting radiofrequency (SRF) gun. The LEI is intended to enable extending the LCLS-II-HE’s useful photon energy to 20 keV without additional cryomodules. We consider a robust two-slit emittance measurement optimized for the LEI SRF gun, compatible with the current LEI...
We develop an alternative theory of coherent synchrotron radiation (CSR) wakefield using the transverse field solution of Maxwell equations in angular domain. This approach allows us to retain only the radiative interaction between particles and cure the frequently encountered divergence in retarded potentials. We analyze the classical radiation reaction force and mass renormalization induced...
A critical factor in determining the limit of the brightness of an electron beam is the mean transverse energy (MTE) of its source, which describes the spread in transverse momentum of electrons at the moment of emission from the source. To increase beam brightness, there has been much work in growing novel photocathodes with low MTE and high quantum efficiency (QE) near threshold...
The spontaneous emission of radiation from relativistic electrons within a plasma channel is called betatron radiation and has great potential to become a compact x-ray source in the future. We present an analysis of the performance of a broad secondary radiation source based on a high-gradient laser-plasma wakefield electron accelerator. The purpose of this study is to assess the possibility...
The strength of a first-order spin-orbit resonance is defined as the amplitude of the corresponding Fourier component of the spin-precession vector. However, it is possible to obtain the resonance strength without computing the Fourier integral directly. If a resonance is sufficiently strong, then to a good approximation, one can neglect all other depolarizing effects when near the resonance....
A superconducting radio frequency (SRF) cryomodule (CM) for the International Linear Collider (ILC) Technology Network (ITN) is being developed at KEK. In the scope of this, a waveguide system is being designed. Its main features are a low center of gravity, a reduced number of corners and waveguide elements, and a compact bellow for connecting it to the input power coupler. Furthermore, the...
The Spallation Neutron Source accelerator is the highest power proton accelerator in the world, operating with over 1.4 MW with high reliability. Commissioned in 2006, it took thirteen years to achieve the 1.4 MW design goal of the facility and required overcoming tremendous technological challenges. The SNS path to high power has significantly influenced the outlook for future of high-power...
Sustainability of accelerators construction and operation is becoming a driver for new accelerators at the high-energy and beam power frontier. The ICFA Panel on Sustainable Accelerators and Colliders assesses and promotes developments on energy efficient and sustainable accelerator concepts, technologies, and strategies for operation, and assess and promote the use of accelerators for the...
Storage rings and free electron lasers use undulators to produce high-brilliant X-ray photon beams. In order to increase brilliance and photon energy tunability it is necessary to enhance the undulator magnetic peak field on axis by reducing its period without decreasing the electron beam stay clear. Undulator technologies aiming to reach this goal are presented.
We will review of the current state of the advanced photocathode material development and structures necessary for production of electron beams with high brightness, high charge, and electron spin polarization.
Recently, Optical Stochastic Cooling (OSC) became the first demonstrated method for ultra-high-bandwidth stochastic cooling. The initial experiments at Fermilab’s IOTA ring explored the essential physics of the method and demonstrated cooling, heating and manipulation of beams and single particles. Having been validated in practice, with continued development, OSC carries the potential for...
Synchrotron light sources and free electron lasers (FELs) have established as powerful research tools in various disciplines, as physics, chemistry, biology, materials science, and medicine. During the last decade new developments and advancements, leading to construction of new facilities and upgrades to existing ones, have allowed to further extend their capabilities to drive scientific...
This presentation discusses the generalization of the two-dimensional impedance model in the presence of an electron cloud. It will be discussed the implementation of a linear model of the e-cloud forces including both dipolar and quadrupolar forces to improve the modeling of the electron cloud instabilities. The linear model is included in the Vlasov equation, which allows for finding...
The last decade has seen a renaissance of machine physics studies and technological advancements worldwide which aim at upgrading storage ring light sources to the diffraction limit up to few hundreds of keV photon energy. This is expected to improve the spectral brightness and the transversally coherent fraction of photons by several orders of magnitude in the X-ray wavelength range. This is...
While designed to be inherently stable, the accelerator upgrade SLS 2.0 will have a longitudinal multi-bunch feedback system, to be used as a diagnostics device and as a fallback against unexpected problems. Modelling the performance of the system is complicated by the presence of a passive harmonic cavity introduced for longer bunch lengths and correspondingly higher stability thresholds,...
A light source project named Very Compact Inverse Compton Gamma-ray Source (VIGAS) is under development at Tsinghua University. VIGAS aims to generate monochromatic high-energy gamma rays by colliding a 350 MeV electron beam with a 400-nm laser. To produce a high-energy electron beam in a compact accelerator with a length shorter than 12 meters, the system consists of an S-band high-brightness...
Low Level RF (LLRF) control systems of linear accelerators (LINACs) are typically implemented with heterodyne based architectures, which have complex analog RF mixers for up and down conversion. The Gen 3 RF System-on-Chip (RFSoC) device from AMD Xilinx integrates data converters with maximum RF frequency of 6 GHz. That enables direct RF sampling of C-band LLRF signal typically operated at...
We present the design and initial characterization of a multi-mode cavity, a novel electromagnetic structure with potential benefits such as compactness, efficiency, and cost reduction. The 2nd Harmonic mode was chosen to linearize the fundamental mode for use as an accelerating and bunching cavity. The reduction in the number of cavities required to bunch and accelerate promises cost and...
Measuring longitudinal beam parameters is key for the operation and development of high-intensity linear accelerators but is notoriously difficult for ion beams at non-relativistic energies. The Bunch Shape Monitor (BSM) is a device used for measuring the longitudinal bunch distribution in a hadron linac. RadiaBeam has developed a BSM prototype with enhanced performance, integrating several...
LCLS-II-HE is an ongoing project to upgrade SLAC's superconducting linac. The upgrade will add 23 cryomodules with a total of 192 nine-cell 1.3 GHz nitrogen-doped niobium cavities. The production and qualification testing of these cavities is nearly complete. To date, they have achieved an average maximum gradient of 27.0±3.5 MV/m and an average Q0 of 3.24±0.38e+10 at the nominal operating...
Microbunching - or short-wavelength – instabilities are well-known for drastic reduction of the beam quality, its filamentation and strong amplification of the noise in a beam. Space charge and coherent synchrotron radiation (CSR) are the leading causes for such instability. In this paper we present rigorous 3D theory of such instabilities driven by the space-charge forces. We define the...
The muon is a unique particle. It is an elementary particle similar to the electron, but with a mass approximately 200 times greater. Because of their high penetrating power, muons can also be used for imaging such as non-destructive inspection and muon tomography for interior surveys of large structures. Muons derived exclusively from cosmic rays have heretofore been used for these...
In this contribution, we investigate electrostatic traps as a novel source of positron beams for accelerator physics applications. Penning-Malmberg (PM) traps are commonly employed in low-energy antimatter experiments. Positrons contained in the trap are cooled to room temperature or below. We calculate the thermal emittance of the positrons in the trap and show that it is comparable to or...
X-rays in the water window (2.33 nm to 4.40 nm wavelength) can be used to provide high quality images of wet biological samples. Given the limited availability of current generation light sources in this energy range, table-top water window X-ray sources have been proposed as alternatives. We present start-to-end simulations in RF-Track of a water window X-ray source based on inverse Compton...
With the development of the steady state micro bunching (SSMB) storage ring, its parameters reveal that the ultra relativistic assumption which is wildly used is not valid for the electron beam bunch train, which has length in the 100 nm range, spacing of 1 μm and energy in hundreds MeV range. The strength of the interaction between such bunches and the potential instability may need careful...
The Future Circular Collider (FCC) study includes two accelerators, a high-energy lepton collider (FCC-ee) and an energy-frontier hadron collider (FCC-hh). Both machines share the same tunnel infrastructure. We present the current design status of FCC-hh, highlighting the most recent changes, including a new layout following updated tunnel dimensions, a change from 12 to 16 dipoles per cell...
The mitigation of collective beam effects, in particular Coherent Synchrotron Radiation (CSR), is crucial for the development of particle accelerators with higher beam brightness. Among the strategies proposed in the literature, the use of appropriate shielding walls to curb CSR is an attractive strategy with many associated open problems. In particular, simulation methods that account for...
THz (1e+12 Hz) radiation is very attractive for its non-ionizing penetrative nature and unique absorption in water, metals, and other chemicals. While THz has great potential for imaging and for diagnosing chemical traces, it has not been utilized extensively due to scarcity of high-power THz sources. Currently, compact THz sources deliver power in the range of 50 μW — 0.5 W, insufficient for...
The Round to Flat Beam Transformation (RFBT) is one of the emittance exchange techniques that can improve the Luminosity for the future accelerator project International Linear collider (ILC). RFBT experiment can be conducted in the KEK-STF, and the expected performance is 334 in emittance ratio. In December 2023, we performed a pilot experiment at STF to optimize the injector conditions. To...
A particle accelerator is a time-varying complex system whose various components are regularly perturbed by external disturbances. The tuning of the accelerator can be a time-consuming process involving manual adjustment of multiple components, such as RF cavities, to minimize beam loss due to time-varying drifts. The high dimensionality of the system (~100 amplitude and phase RF settings in...
Owing to strong 10-100 GV/m accelerator gradients, Laser Plasma Accelerators (LPAs) have the capability to generate high-brightness and high-energy electron beams in compact facilities. The (sub)PW laser systems that drive LPAs are currently operating at 1-10 Hz repetition rates, while the next generation of multi-kHz technologies are being aggressively pursued at various R&D facilities...
A new, rapidly converging cavity optimization tool is presented that uses adjoint methods. The tool is able to work with any cavity solver that can output and input the results of cut-cell meshing of a cavity. Because it is an adjoint method, one needs only a single forward solve for each iteration in the process of convergence. One also needs a backward solve for each optimization target or...
Dielectric laser acceleration (DLA) is a promising approach to accelerate single electrons at a high repetition rate to GeV energies, for indirect dark matter searches. Relevant concepts include the integration of the dielectric structure inside the laser oscillator. To efficiently use muons for high energy physics applications, they need to be accelerated rapidly, before they decay. Plasma...
The Electron-Ion Collider (EIC) will use swap-out injection scheme for the Electron Storage Ring (ESR) to overcome limitations in polarization lifetime. However, the pursuit of highest luminosity with the required $28~\mathrm{nC}$ electron bunches encounters stability challenges in the Rapid Cycling Synchrotron (RCS). One method is to inject multiple RCS bunches into a same ESR bucket. In this...
This study explores various neural network approaches for simulating beam dynamics, with a particular focus on non-linear space charge effects. We introduce a convolutional encoder-decoder architecture that incorporates skip connections to predict transversal electric fields. The model demonstrates robust performance, achieving a root mean squared error (RMSE) of $0.5\%$ within just a few...
A new growth chamber at the High ElectRon Average Current for Lifetime ExperimentS (HERACLES) beamline at Cornell has been installed enabling Negative Electron Affinity (NEA) activations of GaAs using Cs-Sb-O and Cs-Te-O recipes. These activation recipes have been shown to be more robust against vacuum poisoning when measured at low voltages and currents. In this proceeding we present charge...
Strong field Terahertz (THz) light source has been in-creasingly important for many scientific frontiers, while it is still a challenge to obtain THz radiation with high pulse energy at wide-tunable frequency. In this paper, we introduce an accelerator-based strong filed THz light source to obtain coherent THz radiation with high pulse energy and tunable frequency and X-ray pulse at the same...
A beam physics design has been carried out for a 200 MeV-LWFA injector to the AWAKE Run 2 experiment as an alternative to the reference RF injector. It is composed of a laser-plasma acceleration stage and a transport line. In addition to specific environment constraints that impose a dogleg configuration, the electron beam must feature unprecedented performances for a plasma-based accelerator:...
Multipacting is a phenomenon arising from the emission and subsequent multiplication of charged particles in accelerating radiofrequency (RF) cavities, which can limit the achievable RF power. Predicting field levels at which multipacting occurs is crucial for optimizing cavity geometries. This paper presents a new open-source Python code for analyzing multipacting in 2D axisymmetric cavity...
The development of a robust spin-polarized electron source capable of sustaining mA scale average beam currents in a photoinjector is critical for many future accelerator facilities such as the International Linear Collider (ILC). In this proceeding we overview the several efforts being carried out at Cornell towards this end, including: high current (>1 mA) gun tests of robust activation...
An ion cloud confined in a Paul trap eventually reaches a Coulomb crystalline state when strongly cooled toward absolute zero. The normalized emittance of the Coulomb crystal can be in the sub-femtometer range. The trap is thus usable as a unique ion source for nano-beam production, though the available beam intensity is limited. This new concept was first discussed nearly 20 years ago* and...
The Electron-Ion Collider (EIC) requires continuous replacement of the stored electron bunches to facilitate arbitrary spin patterns in the Electron Storage Ring (ESR). This is accomplished by a dedicated, spin transparent Rapid Cycling Synchrotron (RCS). The dynamic range of the accelerator is from 400 MeV to 18 GeV. To maintain stability throughout the acceleration ramp, the linear and...
In a generalized longitudinal strong focusing (GLSF) approach employed in steady-state microbunching (SSMB) storage rings, the objective is to achieve complete cancellation of modulations by ensuring that a particle's longitudinal position remains unchanged after passing through both modulators. This requires effective control over the deviation in longitudinal position, which arises from...
The Electron-Ion Collider (EIC) plans to utilize the local crabbing crossing scheme. This paper explores the feasibility of adopting a single crab cavity with adjusted voltage, inspired by the successful global crabbing scheme in KEKB, to restore effective head-on collisions. Using weak-strong simulations, the study assesses the potential of this global crabbing scheme for the EIC while...
Attosecond X-ray free-electron lasers can deliver isolated sub-fs pulses with a peak power that surpasses conventional table-top sources by more than six orders of magnitude in the soft X-ray region [1]. The intensity at the focus is sufficient for non-linear X-ray spectroscopy methods, and two-color configurations enable applications such as attosecond pump/attosecond probe experiments.
I...
At the Facility for Advanced Accelerator Experimental Tests (FACET-II) accelerator, a pair of 10 GeV high-current electron beams is used to investigate Plasma Wakefield Acceleration (PWFA) in plasmas of different lengths. While PWFA has achieved astonishingly high accelerating gradients of tens of GeV/m, matching the electron beam into the plasma wake is necessary to achieve a beam quality...
The complexity of the GSI/FAIR accelerator facility demands a high level of automation in order to maximize time for physics experiments. Accelerator laboratories world-wide are exploring a large variety of techniques to achieve this, from classical optimization to reinforcement learning. This paper reports on the first results of using Geoff at GSI for automatic optimization of various beam...
In this work, we investigate the transverse dynamics of a single particle in a model integrable accelerator lattice, based on a McMillan axially symmetric electron lens. Although the McMillan e-lens has been considered as a device potentially capable of mitigating collective space charge forces, some of its fundamental properties have not been described yet. The main goal of our work is to...
We present a novel method for minimizing the effects of radiative depolarization in electron storage rings by use of vertical orbit bumps in the arcs. Electron polarization is directly characterized by the RMS of the so-called spin orbit coupling function in the bends. In the Electron Storage Ring (ESR) of the Electron-Ion Collider (EIC), as was the case in HERA, this function is excited by...
The high-luminosity, 10e+33 — 10e+34 cm-2s-1 (e-p), Electron-Ion Collider is presently being developed at Brookhaven National Laboratory in partnership with the Jefferson Laboratory. Beam commissioning is planned right after the installation is complete and after passing all necessary reviews, including the Accelerator Readiness Reviews. Initially, the detector performance testing and...
Beam diagnostic technology is one of the foundations of large particle accelerator facilities. A challenge with operating these systems is the measurement of beam dynamics. Many methods such as beam position monitors have an inherent destructive quality to the beam and produce perturbations after the measurement. The ability to measure the beam conditions with non-destructive edge radiation...
The LCLS-II is a high repetition rate upgrade to the Linac Coherent Light Source (LCLS) and will offer photon science users an unprecedented million pulses per second. However, the accelerating gradient on the cathode of the Very-High-Frequency photoinjector is relatively lower compared to traditional electron guns, the longitudinal beam dynamics become more complicated as required to achieve...
The paper introduces design and optimization of a high-repetition-rate infrared terahertz free-electron laser (IR-THz FEL) facility, which leverages optical resonator-based FEL technology to achieve a higher mean power output by increasing pulse frequency. Electron beam of the facility will be generated from a photocathode RF gun injector and further accelerated with a superconducting linear...
Charge-exchange injection is a key to overcome the Liouville's theorem and to get over the intensity barrier. Specifically negative hydrogen linac injector for a ring is mostly used to obtain high intensity pulsed proton beam for high-energy physics or neutron application. However, different from proton linac, beam loss due to stripping can be a significant issue. For instance, the intra-beam...
The MITHRA facility being commissioned at UCLA, will be capable of producing low emittance beams with 100s pC of charge with bunch lengths in the 100s of fs range having an energy of 60 MeV. This can be used to drive plasma wakefields and the long bunch length compared to the plasma skin depth allows us to create a beam with a broadband energy spectrum. The energy spectrum resembles the...
Parallel beam-based alignment (PBBA) techniques can be used to determine the magnetic centers for multiple magnets with simultaneous measurements and are much faster than traditional methods which target one magnet at a time. The PBBA techniques are very desirable for commissioning larger machines such as the Future Circular Collider (FCC). In this study, we applied PBBA techniques on...
Recently exact Hamiltonian integrators have been added for drift, multipoles and dipoles in Accelerator Toolbox. This paper reports the tracking simulations benchmarks performed to compare with the results provided by MADX-PTC for four lattices: FODO, DBA, H7BA and FCC-HFD@Z. Tracking times are also reported for completeness. The agreement in 4D is complete while small discrepancies persist...
The bunch-to-bunch energy control of the electron beam is crucial in the continuous wave XFEL facility. Recently, a delay system based on Double Bend Achromat (DBA) was proposed for the SHINE linear accelerator to achieve this goal. On this basis, we further optimize this structure to realize the bunch compression/decompression while maintaining the electron beam qualities. Here, we will...
One of the main methods to generate X-rays is to bombard metal targets with electron beams. However, this process introduces uncertainty in the electron transport, which leads to uncertainty in the position and momentum of the secondary X-rays. As a result, the focal spot of the X-rays is larger than the electron beam. In this paper, we use the Monte Carlo software Geant4 to investigate the...
The initial design of the capture cavities for a continuous wave (CW) polarized positron beam for the Continuous Electron Beam Accelerator Facility (CEBAF) upgrade at Jefferson Lab is presented. A chain of standing wave multi-cell copper cavities inside a solenoid tunnel are selected to bunch/capture positrons in CW mode. The capture efficiency is studied with varying cavity gradients and...
In a high-energy circular electron-positron collider like the Future Circular Collider (FCC-ee) at CERN, synchrotron radiation (SR) presents a significant challenge due to the radiation load on collider magnets and equipment in the tunnel like cables, optical fibers, and electronics. The efficiency of the anticipated photon absorbers in the vacuum chambers depends on the operational beam...
Near-adiabatic capture into an RF bucket with rising voltage has been used since 1946 or earlier. But until the present work, there is no analytic and deterministic description of the process capable of predicting the final phase space distribution (for arbitrary voltage ramps). Recently, we have developed formulae for trajectories that cross the instantaneous separatrix, and the corresponding...
A single-pass THz free-electron laser (FEL) at the Photo Injector Test facility at DESY in Zeuthen (PITZ) was designed and implemented for a proof-of-principle experiment on a tunable high-power THz source for pump-probe experiments at the European XFEL. THz pulses are generated at a radiation wavelength of 100 μm within a 3.5 m long, strongly focusing planar LCLS-I undulator. High gain is...
FEL oscillators typically employ a two-mirror cavity with spherical mirrors. For storage ring FELs, a long, nearly concentric FEL cavity is utilized to achieve a reasonably small Rayleigh range, optimizing the FEL gain. A challenge for the Duke storage ring, with a 53.73 m long cavity, is the characterization of FEL mirrors with a long radius of curvature (ROC). The Duke FEL serves as the...
An ultrafast laser system for driving the photocathode RF gun at the European XFEL has been recently put into operation. The new laser system, NExt generation PhotocAthode Laser (NEPAL) is capable of providing drive laser pulses of variable pulse lengths and shapes, supporting the facility to extend its capabilities to operate in multiple user-desirable FEL modes. In this paper, we present a...
Photocathodes at Negative Electron Affinity (NEA), like GaAs and GaN, allow for efficient production of spin-polarized electrons. When activated to NEA with cesium and an oxidant, they are characterized by an extreme sensitivity to chemical poisoning, resulting in a short operational lifetime. In this work, we demonstrate that deposition of a cesium iodide (CsI) layer can be used to enhance...
A general theory of symplectic tracking under the influence of space charge force is not yet available, even if some specific solution was proposed [1, 2]. In this paper we will first review how the pull-back of the Lie transform can be used to self-transport the beam distribution and its associated electromagnetic potential under the effect of the space-charge. We will then classify the...
X-ray free-electron lasers (XFELs) have emerged as a promising counterpart to high harmonic generation sources for scientific applications requiring high power attosecond X-ray pulses. To date, attosecond XFELs have specialized in producing isolated pulses enabling the study of nonlinear ultrafast science in the impulse regime. We present a method to coherently shape the spectrotemporal...
The ongoing Plasma-driven Attosecond X-ray source experiment (PAX) at FACET-II aims to produce coherent soft X-ray pulses of attosecond duration using a Plasma Wakefield Accelerator [1]. These kinds of X-ray pulses can be used to study chemical processes where attosecond-scale electron motion is important. For this first stage of the experiment, PAX plans to demonstrate that <100 nm bunch...
The program to upgrade CEBAF cryomodules has been implemented to enhance the energy gain of refurbished cryomodules up to 75 MeV. This strategy involves reusing the waveguide end-groups from original CEBAF cavities produced in the 1990s, and existing five elliptical cell cavities are replaced with a new optimized cell shape cavity constructed from large-grain, ingot Nb material. Following...
This work presents the design of a compact high-efficiency terahertz source, a collaborative effort between UCLA and RadiaBeam Technologies. The system, driven by a thermionic RF gun, features prebunching elements including alpha-magnet and electromagnetic chicane to effectively compress the long beam generated from the gun. By sending such beam into tapering enhanced waveguide oscillator, we...
We discuss a compact, laser-plasma-based scheme for the generation of positron beams suitable to be implemented in an all-optical setup. A laser-plasma-accelerated electron beam hits a solid target producing electron-positron pairs via bremsstrahlung. The back of the target serves as a plasma mirror to in-couple a laser pulse into a plasma stage located right after the mirror where the laser...
Ion beams from laser-driven plasma sources can provide ultra-short (10s of fs for 10s of MeV), ultra-low slice emittance (10s of nm), and high-charge (100s of pC) properties. Demonstrated maximum energies for laser-ion sources are just short of those needed for pivotal applications, such as proton tumor therapy. Here, a robust and energy-scalable concept is presented that could boost the...
The question of the mitigation of the Transverse Mode Coupling Instability (TMCI) by space charge has been discussed for more than two decades. Since few years, it has become clear that the ABS model, which has been often used in the past and which assumes an air-bag bunch in a square well, is not sufficient to properly describe the complexity of the interaction between impedance and space...
HZB is currently designing the lattice for BESSY III, the successor of the 1.7 GeV electron storage ring running in Berlin since 1998. HZB follows a deterministic lattice design strategy, where the natural substructures of a non-hybrid MBA lattice are optimized separately. The substructures consist of only a few parameters, that can be derived from the strategic goals of the project. In the...
This paper explores the phenomenon of asymmetric blowout in plasma wakefield acceleration (PWFA), where the transversely asymmetric beam creates a transversely asymmetric blowout cavity in plasma. This deviation from the traditional axisymmetric models leads to unique focusing effects in the transverse plane and accelerating gradient depending on the transverse coordinates. We extend our...
Meaningful prediction and enhancement of spin-polarization in the RHIC/EIC accelerator complex relies on accurate modeling of each sub-component. Here we describe a symplectic field approximations of both Siberian Snakes in the AGS, enabling practical long-term tracking calculations. Without such symplectic representations, particle motion destabilizes very quickly close to injection energy....
The linac-based single-pass FEL has been successfully operated
in the EUV and x-ray regions for about two decades. However, the oscillator FEL has been limited to operating in the longer wavelength region. This limitation arises from the challenge of obtaining short-wavelength FEL mirrors with high reflectivity, thermal stability, and radiation resistance. With the Duke storage ring FEL, we...
An electron beam degrader is under development with the objective of measuring the transverse and longitudinal acceptance of the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab. This project is in support of the CE+BAF positron capability. Computational simulations of beam-target interactions and particle tracking were performed integrating the GEANT4 and Elegant...
The conceptual design of the laser-plasma-based soft X-ray Free Electron Laser at ELI-Beamlines involves the integration of a novel high-power, high-repetition-rate laser, plasma source, compact LPA-based electron beam accelerator, dedicated electron beam line with relevant diagnostics, undulator beam line, photon beam line with required diagnostics, as well as a photon beam distribution...
The ELBE radiation source at HZDR has a long success story of delivering bright and powerful infrared and THz beams to a broad user community. Following the science driven user requests we have written a conceptual design report for the Dresden Advanced Light Infrastructure (DALI) as a successor to ELBE.
The proposed DALI facility aims to increase the spectral brightness and pulse energy by...
The muon collider has great potential to facilitate multi-TeV lepton-antilepton collisions. Reaching a suitably high luminosity requires low-emittance high-intensity muon beams. Ionization cooling is the technique proposed to reduce the emittance of muon beams. The Muon Ionization Cooling Experiment (MICE) has demonstrated transverse emittance reduction through ionization cooling by passing...
The Electron Ion Collider design strategy for reaching unprecedented luminosities and detection capabilities involves collision of flat bunches at a relatively large crossing angle. Effective head-on collisions are restored using crab cavities, which introduce a correlation of the particles' transverse coordinates with their longitudinal positions in the bunch, or crab dispersion. The...
Power limitations are expected at injection energy for the main Radio Frequency (RF) system due to the doubled bunch intensity in the High Luminosity (HL-) Large Hadron Collider (LHC) era. One way to overcome these power limitations is to reduce the capture voltage. The smaller RF bucket, however, leads to increased beam losses at the start of the ramp. In practice, these beam losses, which...
The Relativistic Heavy Ion Collider (RHIC) was designed for head-on collisions in the Interaction Regions. However, RHIC operation in recent years necessitated crossing angles to limit collisions to a narrow longitudinal vertex region, which created operating conditions with a large Piwinski angle (LPA). The angles were implemented by adjusting the shunt currents of four dipoles, the D0 and DX...
An upgrade to the Continuous Electron Beam Accelerator Facility (CEBAF) at the Thomas Jefferson National Accelerator Facility (JLAB) to extend its energy reach from 12 GeV to 22 GeV is being explored. The upgrade pushes the boundaries of the current CEBAF facilities and will require several state-of-the-art beamline components. The first of which is nonscaling Fixed Field Alternating (FFA)...
We present measurements of quantum efficiency (QE) modulations in CsSb and Cs3Sb photocathodes that arise from optical interference of reflections from the underlying substrate that has multiple semi-transparent layers. The photocathode films are grown on a cubic silicon carbide layer (3C-SiC) which itself is grown epitaxially on Si(100) during fabrication. We find that the QE modulates by up...
Phase space reconstruction using Neural-Networks and differentiable simulation* is a robust beam diagnostic method to obtain complete 4D phase space including the coupling terms such as (x-y’) and (y-x’). In the first experimental demonstration, it was verified that the RMS beam envelope and normalized emittance from the reconstructed phase space are quantitatively similar to those from the...
This poster will discuss the design of the photocathode vacuum suitcase that we currently design and construct for the Cathodes And Radiofrequency Interactions in Extremes (CARIE) test stand. The CARIE test stand is built to test behavior of the high quantum efficiency photocathodes at strong fields. The semiconductor photocathodes must be grown and delivered to the photoinjector under...
Structured plasma channels are an essential technology for driving high-gradient, plasma-based acceleration and control of electron and positron beams for advanced concepts accelerators. Laser and gas technologies can permit the generation of long plasma columns known as hydrodynamic, optically-field-ionized (HOFI) channels, which feature low on-axis densities and steep walls. By carefully...
An energy-recovery-linac (ERL)-based X-ray free-electron laser (FEL) is proposed considering its three main advantages: i) shortening the linac by recirculating the electron beam by high-gradient SRF cavities, ii) saving the klystron power and reducing the beam dump power through the energy recovery in the SRFs, iii) producing a high average photon brightness with high average beam current....
Laser Wakefield Acceleration (LWFA) can generate a high-energetic electron beam in a short accelerating distance of several cm, which is advantageous for the development of an compact accelerator. The LWFA using metal targets is highly influenced by the field ionization process of metal atoms (or ions) due to the high intensity of main laser. Titanium produces a large amount of ionized...
Shanghai HIgh repetitioN rate XFEL and Extreme light facility (SHINE) is an x-ray FEL facility, consisting of an 8 GeV CW superconducting linac and 3 FEL undulator lines, covering the spectral ranges 0.4-25 keV. Photoinjector using VHF gun is one of the key part of the facility. The installation of the electron gun section of the SHINE injector has been completed in August 2023. RF...
The bunching system of injector Linac in High Energy Photon Source (HEPS) includes two sub-harmonic bunchers, a pre-buncher and a traveling wave S band buncher. The buncher is a 6-cell constant impedance traveling wave structure operating in 2π/3 mode at 2998.8 MHz. In this paper, the design and test of the traveling wave buncher are presented. First, the characteristic parameters are...
Capable of achieving a high repetition rate with strong focusing, Fixed Field Alternating gradient (FFA) accelerators have the potential to be used for pulsed high intensity operations. With no pulsed high intensity FFA ever built so far, a prototype machine called FETS-FFA has been proposed to study the FFA option for the next generation spallation neutron source (ISIS-II). One of the...
Distributed-coupling structures has been proposed as an advanced type of high-gradient accelerators, RF power flow independently into each cavity.This method has few advantages such as high shunt impedance, superior power efficiency, and low costs. And the most distributed-coupling structures typically set 0° or 180° as the phase advance which can simplify the design.In this study we...
The Electron-Ion Collider (EIC) at Brookhaven National Laboratory will feature a 3.8-kilometer electron storage ring (ESR) that will circulate polarized beams with energies ranging from 5 to 18 GeV for collision with hadrons from a separate ring at luminosities up to 10^34 cm^{-2} s^{-1}. This contribution focuses on several recent changes to the lattice design of the ESR. Super-bend dipole...
In the field of structure wakefield acceleration there is considerable interest in radiofrequency (RF) structures capable of producing high gradients. Structures in the sub-terahertz (sub-THz) regime are of note due to their high gradient and high efficiency, allowing for a low physical footprint. In the pursuit of this goal we have designed a metallic corrugated W-band structure using the CST...
Space charge lenses are ion-optical devices that focus an ion beam by the intrinsic electric field of confined non-neutral plasmas, for example electron clouds. This was first proposed by Dennis Gabor in the year 1947 and is therefore also known as Gabor-lenses. Previous studies have shown the strong linear focusing forces of a confined electron plasma. In this paper, the first confinement of...
Stationary CT is a novel CT technology to significantly improve scanning speed, by using distributed multiple ray sources instead of conventional helical rotation with single source. This work presents an S-band multi-beam accelerator as a multiple MV-level X-ray source for industrial stationary CT application. This accelerator consists of 7 parallel-distributed acceleration cavity and 6...
A single wide-momentum-acceptance FFA beam line allows for recirculating a beam several times through a linac. Such a scheme provides an efficient path towards high-energy, high-power continuous beams. This paper describes the development of a conceptual design of an FFA RLA focusing on but not limited to a high-power hadron beam case. We present a complete optics design including arc, linac,...
Many of ion beams generated by the Electron Cyclotron Resonance Ion Source (ECRIS) originate from solid-state materials and undergo a conversion process to transition from a solid to a gaseous state before being introduced into the plasma. Established techniques for thermal evaporation encompass ovens and others. The primary objective is to advance oven technology targeting increased...
A liquid lithium target system is being developed for laser ion sources. Existing laser ion sources are operated at the repetition rate of the order of 1 Hz. The limitation stems from the use of solid laser targets because of the craters created and the need to provide a fresh surface by either repositioning the laser beam or the target. In addition, an enormously large surface area is needed...
Research on heavy ion linac was began more than ten years ago to improve the HIRFL operation. In China, the first continuous wave (CW) heavy ion linac, SSC Linac, working at 53.667 MHz was designed and constructed as the SSC injector. The ion particle can be accelerated to 1.48 MeV/u with the designed A/q=5.17. At present stage, this CW linac has been put into operation and the Uranium has...
Intra-beam Scattering (IBS) is one of the main mechanisms of emittance blowup and performance deterioration in the Large Hadron Collider (LHC) accelerator complex. It is particularly relevant since the recent upgrades across the injector complex to reach the high brightness beams of the High Luminosity LHC (HL-LHC) era have been implemented. Several studies have focused on developing an...
The X-ray Laser Oscillator (XLO) uses LCLS pulses to pump population inversion in solid copper and lase on the K alpha line, producing fully coherent, transform limit X-ray pulses, opening new avenues for experiments in fields such as inelastic X-ray scattering, parametric down-conversion, quantum science, X-ray interferometry, and coherent imaging. An important component of XLO is a bow-tie...
To explore and detect novel effects and mechanisms inherent in materials, a tenable wavelength terahertz free electron laser (THz-FEL) is integrated into the terahertz near-field high-throughput material property testing system (NFTHZ). Employing a compact linear accelerator capable of adjusting electron energy within the range of 10 to 18 MeV as the injector, pre-bunching of electron bunches...
Terahertz radiation sources have significant applications in non-invasive detection fields, including medical imaging, drug design, and the quantification of specific biochemical substances. Currently, accelerator-based terahertz sources play a crucial role in producing high-power terahertz radiation. To achieve high-power Terahertz output, beam manipulation is necessary. This paper presents...
One of the Grand Challenges in beam physics is development of virtual particle accelerators for beam prediction. Virtual accelerators rely on efficient and effective methodologies grounded in theory, simulation, and experiment. We will address one sample methodology, extending the understanding and the control of deleterious effects, for example, emittance growth. We employ the application of...
Electron storage rings in synchrotron light sources are typically composed of 𝑁 identical sectors that repeat over the ring. Transverse plane betatron frequencies are not an integer harmonic of the beam revolution frequency to avoid that accelerator imperfection effects are turn-by-turn amplified causing beam losses. Consequently, orbit variations induced by ring parameters not affecting beam...
Since the start of the Large Hadron Collider (LHC), dust-induced beam loss events resulted in more than hundred premature beam aborts and more than ten dipole quenches during proton physics operation. The events are presumably caused by micrometer-sized dust grains, which are attracted by the proton beams and consequently give rise to beam losses due to inelastic proton-nucleus collisions....
Design of the electron-ion collider (EIC) at Brookhaven National Laboratory continues to be optimized. Particularly, the collider storage ring lattices have been updated. Dynamic aperture of the evolving lattices must be kept sufficiently large, as required. In this paper, we discuss the collider Electron Storage Ring, where the lattice updates include improvements of the interaction region...
Crab crossings are designed to increase the luminosity of accelerators by ensuring beam interactions are closer to a head on collision. One will be implemented at the Electron Ion Collider (EIC) at Brookhaven National Laboratory. It is then important to examine how the crab cavity will affect beam dynamics at the EIC. Methods such as Frequency Map Analysis (FMA) have been shown to be helpful...
The E-320 collaboration is colliding an electron beam generated at FACET-II with a 10 TW laser pulse [1,2]. In the rest frame of the electron beam, the laser field intensity is comparable to the Schwinger limit, allowing for the study of Strong-Field QED (SFQED). In this regime, quantum corrections to classical synchrotron radiation become important and the probability for electron positron...
Cavity-based XFEL, or CBXFEL, is a future photon source concept under intense development at SLAC. It is considered a path towards full 3D coherence at angstrom wavelength, delivering another 2-3 orders of magnitude leap in source brightness compared to current XFELs configurations. In a first phase of the project, one of the goals is to demonstrate the regenerative amplification by returning...
The EIC electron storage ring has very tight tolerances for the amplitude of electron beam position and size oscillations at the interaction point. The oscillations at the proton betatron frequency and its harmonics are the most dangerous because they could lead to unacceptable proton emittance growth from the oscillating beam-beam kick from the electrons. To estimate the amplitude of these...
ALBA, the Spanish third generation synchrotron light source, is studying the future construction in the same location of a fourth generation light source called ALBA-II. Since the construction of ALBA in 2008, its critical slab has moved significantly, changing with it the accelerator elements positions. In this study, the effects on closed orbit and beam optics errors are simulated from data...
The front end of the 800-MeV proton linac at the Los Alamos Neutron Science Center (LANSCE) is still based on Cockcroft-Walton voltage generators that bring proton and H- beams of various flavors to 750 keV. We have developed 3D CST models of the LANSCE front-end elements including low-frequency and main bunchers. The fields in these elements are calculated with MicroWave and ElectroMagnetic...
In present paper, the coupled effect of spatio-temporal variation of the laser pulse propagating inside magnetoplasma on electron acceleration have been investigated theoretically. The variation in the dielectric properties under the combined effect of relativistic and ponderomotive non-linearity have been taken into account. Two coupled second order non-linear differential equations...
In this paper, beam dynamics simulations in a compact 200 kV DC electron gun at Tsinghua University are carried out and pm·rad-scale low normalized transverse emittance is obtained in the preliminary results. Small emission areas and low initial electron energies contribute to the generation of beams with low transverse emittance. We used electrochemical etching to fabricate tips for cold...
We experimentally and numerically demonstrate that electron beam energy spread produced by laser heating can be used for shaping electron beam current profile. In particular, we introduce this method for generating attosecond pulse duration X-ray free electron laser. Electron beam scattering material (slotted foil) is additionally used for final selection of the effective current profile. This...
High current electron bunches with lower emittance and slice energy spread are required to generate the intense XFEL. However, it is difficult to maintain the emittance and slice energy spread during the bunch compression at magnetic bunch compressors (BC). The higher current peaks in the head and tail of compressed bunches spoil the core slices by the wakefield and coherent synchrotron...
The FERMI free-electron laser makes use of electron bunches in the 50 fs to 1 ps range. After the FEL process, the spent electron bunches are sent through a thin metallic foil placed in the main beam dump, where coherent transition radiation with THz frequencies is generated and transported to the TeraFERMI beamline. Intensity and spectral properties of those THz pulses strongly depends upon...
GaAs-based photocathodes can provide electron beams with high spin-polarization. In order to be used in a photo-gun for high-current applications such as energy-recovery linacs and colliders, the quantum efficiency as well as the lifetime of the photocathode needs to be as high as possible. Both parameters depend on the quality of the thin layer that is applied to the photocathode surface...
Brookhaven National Laboratory is presently implementing dedicated accelerator research space to support development of accelerator technology for industrial, security, and medical applications. The need for such research capacity was identified through interactions with non-DOE organizations needing support in the development of accelerator technology as part of outreach events supported by...
The utilization of machine learning techniques in accelerator research has yielded remarkable advancements in optimization strategies. This paper presents a pioneering study employing a machine learning algorithm, GPTune, to optimize beam intensity by adjusting parameters within the EBIS injection and extraction beam lines. Demonstrating significant enhancements, our research showcases a...
The Super Proton Synchrotron at CERN serves the fixed-target experiments of the North Area, providing protons and ions via slow extraction, and employs the crystal shadowing technique to significantly minimize losses. Over the past three operational years, the use of a crystal, positioned upstream of the electrostatic septum to shadow its blade, has allowed to achieve a 25% reduction in...
Accelerator-driven high brilliance neutron sources are an attractive alternative to the classical neutron sources of fission reactors and spallation sources to provide scientists with neutrons. A new class of such neutron facilities has been established referred to as High-Current Accelerator-driven Neutron Sources (HiCANS). The basic features of HiCANS are a medium-energy proton accelerator...
We report on a week-long study of a conceptual design of EUV FEL light source based on an energy recovery linac with on-orbit laser plasma accelerator injection scheme. We carried out this study during USPAS Summer 2023 session of Unifying Physics of Accelerators, Lasers and Plasma applying the art of inventiveness TRIZ. An ultrashort Ti-sapphire laser accelerates electron beams from a gas...
THz-frequency accelerating structures could provide the accelerating gradients needed for compact next generation particle accelerators. One of the most promising THz generation techniques for accelerator applications is optical rectification in lithium niobate using the tilted pulse front method. However, accelerator applications are limited by losses during transport and coupling of THz...
The Large Hadron Collider (LHC) employs special optics and configurations, alongside low-beta* collision optics, to address specific experimental requirements. These include calibrating luminosity monitors (vdM) and facilitating forward physics measurements in TOTEM and ALFA experiments (high-beta). The special optics have been in use since Run 1, and for Run 3, they have been updated for...
The present ion physics program in the CERN accelerator complex is mainly based on lead (Pb82+) ion beams. Lighter ions have been considered both by the ALICE3 detector upgrade proposal at the Large Hadron Collider (LHC) --- as a potential way to achieve higher integrated nucleon-nucleon luminosity compared to the present Pb beams --- and also by the Super Proton Synchrotron (SPS) fixed-target...
The physical realization of integrable Hamiltonian dynamics provides promising avenues for investigations of new particle accelerators, best demonstrated by the Integrable Optics Test Accelerator (IOTA) at Fermilab. The core concept of IOTA centers around the results of the Danilov-Nagaitsev paper, where taking the paraxial approximation of the Hamiltonian for a charged particle can lead to a...
Echo-enabled harmonic generation (EEHG), a free-electron laser (FEL) scheme relying on two modulating sections, each consisting of an optical seed laser, an undulator and a magnetic chicane, has recently been implemented on the FEL-1 radiator line at the FERMI FEL user facility in Trieste, Italy. This setup imprints a density modulation onto a relativistic electron beam at a high harmonic of...
Plasma wakefield acceleration is nowadays very attractive in terms of accelerating gradient, able to overcome conventional accelerators by orders of magnitude. However, this poses very demanding requirements on the accelerator stability to avoid large instabilities on the final beam energy. In this study we analyze the correlation between the driver-witness distance jitter (due to the RF...
Dielectric-lined waveguides have been extensively studied for high-gradient acceleration in beam-driven dielectric wakefield acceleration (DWFA) and for beam manipulations, including the application of zero transverse force modes in the waveguides. In this paper, we investigate the zero transverse force modes excited by a relativistic electron bunch passing through a dielectric waveguide with...
In non-linear optics, achieving integrability can enhance the dynamic aperture in storage rings. We analyze turn-by-turn phase-space data from our Danilov-Nagaitsev lattice implementation at Fermilab's Integrable Optics Test Accelerator using machine learning. AI Poincaré estimates conserved quantities from experimental data without prior knowledge of the invariant structure, showing...
Transverse resonance island buckets (TRIBs) near a third-order resonance are observed at the Cornell Electron Storage Ring with a newly-designed lattice. Hamiltonian perturbation theory and map-based PTC method have been successfully implemented to design the TRIBs lattice and find the fixed points near the third-order resonance. For even higher order resonances which are intrinsically weaker,...
Laser Doppler cooled ion traps can produce stationary bunches of ions with extremely low velocity spread (0.6 m/s RMS) and emittance (10e-13 m normalized). This corresponds to temperatures of a few milli-Kelvin and allows the ions to settle into a fixed lattice analogous to a solid crystal, but with the Coulomb repulsion balanced by the trapping force, rather than a chemical bond. Extraction...
We show how a chicane with anomalous dispersion can be used to compress an electron beam into a narrow, high-current, spike by exploiting the intrinsic chirp created by collective effects. We explore the limits of compression in a linearized model and then apply these beams to impulsively pump valence electrons. In the limit of an ultrashort electron beam, the valence electron wave-packet is...
A new X-band phase shifter for the Very Compact Inverse Compton Scattering Gamma-ray Source (VIGAS) program in Tsinghua University has been fabricated and conducted high-gradient testing. After 10 h of conditioning in the Tsinghua X-band high-power test stand (TPOT), the phase shifter reached a peak power of 72 MW at 230 ns pulse width, and peak power of 82 MW at 130 ns pulse width.
A new X-band mode converter for the Very Compact Inverse Compton Scattering Gamma-ray Source (VIGAS) program in Tsinghua University has been fabricated and conducted low-power testing. S11 is under -30 dB with -0.05 dB of S21 at the operating frequency of 11.424GHz according to the low-power test using the vector network analyzer, which is consistent with simulation results.
A corrugated waveguide based collinear wakefield accelerator is under development at Argonne National Laboratory. The accelerating mode is operating at 180 GHz with a high average power level up to 600 W compounding at the end of the 0.5 m long accelerator module. It is extracted by a dedicated coupler to prevent excessive heating of the corrugated structure of the next accelerator module...
In a preceding study, the wakefield accelerator, which is being actively researched worldwide, was successfully developed by the die stamping method. In order to realize smaller and more precise structure for future wakefield accelerators, X-ray based lithography is successfully implemented to fabricate micro-meter scale wakefield structure. The fabricated structure is half mm radius and 400...
We have fabricated corrugated structures for sub-THz regime by stacking disks. By sending electron beams into the structure, the wakefield of 200 GHz was successfully measured. The frequency and power levels of wakefield were very similar to our design. For the our next target of gigawatts power, we have newly designed a structure of 400 GHz. More precise fabrication is required compared to...
RadiaBeam is designing and manufacturing a fast-ramping alpha magnet is developed for interleaved operation at the Argonne Advanced Photon Source (APS). This interleaving operation requires the alpha magnet to stably complete a 5 s long cycle with a 100 ms ramp-up, 1000 ms nominal field output and a 100 ms ramp-down. A laminated yoke is used to minimize eddy currents, ensure fast field...
The Large Hadron Collider (LHC) at the European Organization for Nuclear Research (CERN) is the world's largest and most powerful particle accelerator, colliding beams of protons and lead ions at energies up to 7 ZTeV. ALICE is one of the detector experiments optimized for heavy-ion collisions.
A fixed-target experiment in ALICE is considered to collide a portion of the beam halo, split using...
Most FELs employ the mechanism of self-amplified spontaneous emission (SASE) from a relativistic electron beam to generate intense femtosecond pulses in the x-ray spectral region. Such SASE FELs are characterized by a broad bandwidth and relatively poor longitudinal coherence, and offer a rather limited control over the spectro-temporal properties. The limitations of a SASE FEL can be overcome...
The Continuous Electron Beam Accelerator Facility (CEBAF) is a 12 GeV recirculating electron accelerator at the Thomas Jefferson National Accelerator Facility (JLAB). Major upgrades to the accelerator are being investigated which include a new 650 MeV injection beamline and state-of-the-art fixed-field alternating (FFA) gradient recirculation arcs. The upgrade will extend the energy of the...
Laser wakefield accelerators (LWFAs) have been experimentally shown to produce sustained gradients of tens of GeV/m over tens of centimeters. While the strength of these fields has been demonstrated, a direct measurement of the field configurations inside an LWFA represents an emerging research topic. Here, we report on the results of transverse probing of the fields inside an LWFA at...
This paper presents the final physics design of the Proton Improvement Plan-II (PIP-II) at Fermilab, focusing on the linear accelerator (Linac) and its beam transfer line. We address the challenges in longitudinal and transverse lattice design, specifically targeting collective effects, parametric resonances, and space charge nonlinearities that impact beam stability and emittance control. The...
FLASH, the superconducting XUV and soft X-ray FEL is undergoing a substantial upgrade (FLASH2020+) with two long shutdowns 2021/22 and 2024/25. In the 1st shutdown, FLASH's 2nd bunch compression chicane (BC2) has been completely redesigned for the FLASH2020+ upgrade project. The redesign allowed the installation of two quad/skew-quad packs in each of the arms of the 4-dipole (C-type) chicane....
Light with polarization structure is called Fully Structured Light (FSL). We present an experimental demonstration of coherent FSL EUV light with spatially varying states of polarization generated at the FERMI free electron laser (FEL) in Trieste, Italy. Control of the polarization is obtained through the overlap of radiation emitted in orthogonally polarized helical undulators with different...
Magnetic hysteresis, eddy currents, and manufacturing imperfections pose significant challenges for beam operation in multi-cycling synchrotrons. Addressing the dynamic dependency of magnetic fields on cycling history is a current limitation for control room tools using existing models. This paper outlines recent advancements to solve this, presenting the outcome of operational tests utilizing...
This contribution presents the initial findings from the 3.2 Million Euro EuPRAXIA Doctoral Network. European Plasma Research Accelerator with eXcellence In Applications (EuPRAXIA) is at the forefront of advanced particle accelerator research, focusing on the development of plasma-based accelerator technologies.
The EuPRAXIA Doctoral Network, a collaborative effort among leading research...
High brightness electron beams with high peak current are critical to reducing the size of XFEL. A promising approach consists in combining low emittance beam generated high-frequency photoinjector with a laser-assisted bunch compression scheme. Such a compression consists in using an infrared laser to modulate the electron beam energy in a planar undulator and a low R56 chicane to compress...
We present a novel concept of the Fixed-Field-Alternating (FFA) permanent magnet small racetrack proton accelerator with kinetic energy range between 10-250 MeV. The horizontal and vertical tunes are fixed within the energy range providing very fast cycling with a frequency of 400 Hz to 1.3 KHz. The injector is commercially available cyclotron with RF frequency of 65 MHz. The permanent magnet...
FLASH, the XUV and soft X-ray free-electron laser user facility at DESY, is in the transitional period between two substantial upgrade shutdowns within the FLASH2020+ upgrade project. FLASH consists of a common part FLASH0 (injector & superconducting linac), two FEL beamlines (FLASH1/2) and an experimental beamline FLASH3, accommodating the plasma wakefield experiment FLASHForward. The first...
Particle beams with asymmetric transverse emittances and profiles have been utilized in facilities for driving wakefields in dielectric waveguides and to drive plasma wakefields in plasma. The asymmetric plasma structures created by the beam produce focusing forces that are transversely asymmetric. We utilize the ellipticity of the plasma ion cavity to model the beam evolution of the flat beam driver.
Almost all linac-based free-electron laser (FEL) facilities have employed a symmetric three- or four-dipole chicane to compress the electron beam in order to achieve a kA-level bunch current. The achromatic C-type chicane has been widely used in present linac-FEL facilities. Coherent synchrotron radiation (CSR) induced microbunching instability (MBI) can be an issue in the chicane design....
Laser-field emission, or optical field emission, is a process that can produce electron beams with high charge density and high brightness with ultrafast response times. Using an extended nanostructure, such as a nanoblade, permits plasmonic field enhancement up to 80 V/nm with an incident ultrafast laser of wavelength 800 nm. Stronger ionizing fields lead to higher current densities, so...
We present second-order fringe maps for gradient dipoles whose poles are curved to follow the reference orbit. While some of the results have been previously found, we find new contributions including soft-edge linear terms that can be significant for gradient dipoles. In addition, we depart from previous works by writing all soft-edge corrections in terms of integrals along the particle...
Strong Hadron Cooling (SHC), utilizing the coherent electron cooling scheme, has been extensively investigated for the Electron Ion Collider (EIC). Throughout our cooling optimization studies, we realized that a Super-Gaussian electron bunch offers enhanced performance in comparison to a Gaussian bunch. Our approach involves initiating the electron beam distribution in a double peak form,...
As an important experimental tool, the Optical Frequency Combs (OFCs) has had a profound impact on research in various fields, whereas, generating high power high repetition frequency OFCs at tunable frequencies is still a limitation for most of the existing methods. In this study, free-electron laser (FEL) is proposed to generate coherent X-ray OFC with a tunable repetition frequency and...
Obtaining ultrashort electron bunches is the key to the studies of ultrafast science, yet second and higher order nonlinearities limits the bunch length to a few femtoseconds after compression. Traditional regulation methods using rf higher order harmonics have already optimized the bunch length to sub-fs scale, yet the energy loss and rf jitter are not negligible. In this paper we demonstrate...
Bunch trains have been considered as a promising means of generating intense, coherent radiation in compact accelerator facilities. However, conventional methods, which impart a sinusoidal modulation on the beam’s longitudinal phase space, are inefficient for generating a high bunching factor density modulation. Only a small fraction of a sinusoidal modulation, which has linearity, primarily...
The Electron Ion Collider (EIC), to be constructed at Brookhaven National Laboratory, will collide polarized high-energy electron beams with hadron beams, achieving luminosities up to 1e+34 cm^−2 s^−1 in the center-mass energy range of 20-140 GeV. The Hadron Storage Ring (HSR) of the EIC will utilize the arcs of the Relativistic Heavy Ion Collider (RHIC) and construct new straight sections...
The longitudinal distribution of the electron beam in the electron storage ring of the Electron-Ion Collider will be modified by the machine impedance. The modified distribution, combined with crab cavities may have an impact on the quality of the hadron beam during the collision. In this paper, we will explore the possible impact on the hadron beam quality with strong-strong and...
Hard X-ray self-seeded (HXRSS) free-electron lasers (FEL) provide high intensity radiation pulses with both transverse and longitudinal coherence in the hard X-ray regime. These sources are important for experiments requiring high spectral density and high photon energies like nuclear resonance scattering. However, as the photon energy increases, HXRSS efficiency may decrease in a typical...
The International Linear Collider (ILC) is a next-generation electron-positron collider designed to operate at center-of-mass energies ranging from 250 GeV to 1 TeV, providing opportunities for exploring physics beyond the Standard Model. A critical component of the ILC is the E-driven positron source, which requires sophisticated technology to produce large quantities of positrons....
The international e-e FCC study group aims to design an accelerator complex capable of injecting tunable and high charge electron-positron bunches into a collider with center-of-mass energy between 90 and 365 GeV. The injector complex will boost the initial energy of the electron-positron bunches using multiple linacs accelerating only electrons, only positrons, and both species up to the...
C-band accelerators have been of particular interest in recent years due to their ability to provide high gradients and transport high charge beams for applications such as colliders and medical technologies. New Advancements in high gradient technologies that can suppress the breakdown rate in a particular structure by using distributed coupling, cryogenic cooling, and copper alloys. Previous...
We report simulation results showing the use of sacrificial bunch charge to achieve high brightness in photoinjector beamlines designed for Ultrafast Electron Diffraction (UED) and Inverse Compton Scattering (ICS). The beam undergoes nonlaminar focusing during which the tails dynamically linearize the core’s transverse phase space. An aperture then removes the resulting diffuse tails, leaving...
Future electron accelerator applications such as x-ray free electron lasers and ultrafast electron diffraction are dependent on significantly increasing beam brightness. We have designed and produced a new CrYogenic Brightness-Optimized Radiofrequency Gun (CYBORG) for use in a new beamline at UCLA to study the brightness improvements achievable in this novel low temperature high gradient...
Reliable operation of a seeded Free Electron Laser requires the simultaneous control of several electron-beam, laser and accelerator parameters. With EEHG the complexity increases due to the second seed laser and the strong dependence of EEHG bunching to seeding parameters. With the recent upgrade of the FEL-1 line, FERMI is the first FEL facility to be operated in EEHG mode for users. This...
In a radiofrequency accelerating structure with ceramic insertion, high shunt impedance (162 megaohm/m) and high group velocity (3.1% of the speed of light) are achieved simultaneously. The ceramic insertion is in the form of a cylinder, sandwiched between copper endplates with the beam aperture opened at the center. We report our theoretical study on this novel type of traveling wave...
LCLS-II-HE is an energy upgrade of the LCLS-II linac from 4 GeV to 8 GeV. The X-ray FEL photon energy (Self-Amplified Spontaneous Emission mode) will extend towards 12 keV (from the present 5 keV) based on the current beam emittance. To reach higher photon energy range towards 20 keV, a new injector with a much brighter electron beam will be required. Here we study an X-ray regenerative...
Due to their compactness, laser-plasma accelerators are a promising approach to future energy frontier electron accelerators. To reach multi-GeV energies in a single accelerator stage, the high-intensity drive laser pulse must be kept focused over several tens of centimeters through a sufficiently low density plasma. Without an external guiding mechanism, the laser will diffract reducing the...
We present a high-performance solver for the magnetostatic equations. The solver can simulate nonlinear and anisotropic magnetic materials on a highly variable grid, enabling efficient resolution of fine features even in very large systems. It is built on the Tpetra parallel sparse linear algebra package, allowing it to handle problems with billions of degrees of freedom and employ hardware...
We are researching the development of an ultra-high intensity heavy ion source based on laser ablation ion source (LIS) technology coupled with a unique beam injection technique called Direct Plasma Injection Scheme (DPIS). A metallic target is ablated using a Q-switched Nd:YAG laser to generate a pulsed high-density plasma, which is then injected and accelerated by a radio-frequency...
Imparting designed nonlinear correlation on the longitudinal phase space is nontrivial task. While RF cavities operating at different frequencies can generate arbitrary correlation in principle, it is hard to realize such system due to the lack of RF power sources and their costs. We present a new method that may overcome such practical limitation by adopting transverse wigglers and transverse...
Betatron radiation is a form of synchrotron radiation emitted by moving or accelerated electron or positron-like charged particles. As a valuable tool it can provide useful information about their trajectories, momentum and acceleration. It has good potential as a novel non-destructive diagnostic for laser-driven plasma wakefield acceleration (LWFA) and beam-driven plasma wakefield...
Elettra 2.0, will be a 4th generation synchrotron radiation source that will replace Elettra, the 3rd generation light source that has been in operation since 1993 at Trieste. In this paper, the effects of the quadrupolar wake fields are investigated, and the transverse mode coupling threshold is presented. Also, the incoherent tune shift for multi-bunch operation is examined considering the...
The Los Alamos Neutron Science Center (LASNCE) is over 50 years old. Currently, Cockroft-Waltons are being used to accelerate H+ and H- beams to 750 keV. The LANSCE Modernization Project (LAMP) is proposing to replace the font-end of LANSCE with a Radio-Frequency Quadrupole (RFQ). A RFQ Test Stand is being commissioned at LANL for technical demonstration of simultaneous dual-beam species...
The plasma accelerator community has made significant progress in advancing particle beams, bringing us closer to realizing the dream of replacing the radio frequency (RF) cavities' MV/m fields with the plasma-sustained GV/m fields for collider applications. The beam requirements for realizing this vision emphasize a collider-quality beam featuring hundreds of pC of charge, energy spread less...
Using hollow plasma channels is one approach to compact positron acceleration, potentially reducing the cost and footprint of future linear colliders. However, it is prone to transverse instabilities since beams misaligned from the channel axis tend to get deflected into the channel boundary. In contrast, asymmetric electron drive beams can tolerate misalignment and propagate stably after the...
The operation of light source accelerators is a complex process that involves a combination of empirical and theoretical physics, simulations, and data-intensive methodologies. For example, the FLASH1 beamline at DESY is upgrading to an external seeding FEL light source*. We utilize special diagnostics, machine learning algorithms, and comprehensive simulations to achieve this. To optimize...
The intrabunch motion for independent longitudinal or transverse beam oscillation modes has been explained analytically for impedance driven bunched-beam coherent instabilities already several decades ago by Laclare and they have been observed in many measurements and simulations. These oscillation patterns do not depend on the bunch intensity, they are head/tail symmetric and they exhibit a...
This study focuses on beam generation in the laser back-illumination mode using metal cathodes of varying thicknesses in a 200-kV photocathode DC electron gun. The aim is to investigate the quality and characteristics of beam production in this mode and provide valuable insights for the application of the electron gun in electron microscopy and related fields. Experimental preparations...
The quest for novel technologies in the ever-evolving landscape of scientific exploration has led to the investigation of plasma lensing as a potential solution for optical matching devices for all kinds of positron sources. This research becomes increasingly significant as the need for higher data output demands innovative concepts to increase positron yield and therefore luminosity....
Transfer maps of different ion optical elements are usually obtained via ray tracing methods without taking into account the imperfections and misalignments of the optics. Normally beam profile monitors do not measure the full 6D phase-space, but only a portion of it. To verify the beam phase-space, we have constructed an Ion Optics Test Stand (IOTS) that is located at the Low Energy Branch...
The plasma wakefield accelerator, with acceleration gradients ranging from GeV/m to TeV/m, holds promise for propelling particles to high energies in linear colliders. This results in exceptionally bright beams characterized by intense ion-derived focusing, leading to the collapse of plasma ions. The non-uniform ion density triggers robust nonlinear focusing, potentially resulting in...
Data driven methods have proved to be a useful tool for analyzing Hamiltonian systems. The symplectic condition is a strong constraint on Hamiltonian systems and it is therefore useful to implement this constraint into neural networks to ensure the accuracy of long term predictions about the system. One such method is the use of SympNets*, linear, activation, and gradient layers that guarantee...
Laser-plasma accelerators (LPAs) are compact accelerators with field gradients that are approximately 3 orders of magnitude higher than RF-based machines, which allows for very compact accelerators. LPAs have matured from proof-of principle experiments to accelerators that can reproducibly generate ultrashort high-brightness electron bunches. Here we will discuss a first combination of LPAs...
A muon collider allows one to have a high energy reach for physics studies while having a relatively compact footprint. Ideally such a machine would accelerate muon beams to about 5 TeV. We present a preliminary lattice design for a pulsed synchrotron that will accelerate muon beams to their maximum collision energy and having a circumference of 16.5 km, which would allow it to fit just within...
The Variable Energy Gamma (VEGA) System is under implementation in Bucharest-Magurele Romania as one of the major components in the project of Extreme Light Infrastructure Nuclear Physics (ELI-NP). The VEGA System is designed as an advanced Laser Compton Scattering gamma-ray source with unique parameters in terms of high spectral density, monochromaticity, high polarizability, and energy...
Linac Coherent Light Source (LCLS) copper linac typically functions in a single bunch mode, having a repetition rate of 120 Hertz. Numerous internal projects and external user experiments at the LCLS necessitate X-ray pulse trains consisting of two or multiple pulses. Previously we have reported on implementing a system of two ultra-fast stripline kickers, aimed at correcting pulse train...
In 2023, about 2 months of the LHC operation were devoted to the Heavy Ions physics, after more than 5 years since the last ion run. In this paper, the results of the 2023 Ion optics commissioning are reported. Local corrections in Interaction Point (IP) 1 and 5 were reused from the regular proton commissioning, but the optics measurement showed the need for new local corrections in IP2. We...
The LHC machine configuration was changed in 2023 compared to previous years, requiring a new set of optics configurations to be measured and corrected. A telescopic optics was deployed in energy the ramp for the first time, which gave rise to a beta-beating of up to 25%. This was corrected using a global correction approach which reduced the beta-beat down to 10%. A change in the phase...
SLAC's LCLS-II is rapidly advancing towards MHz repetition rate attosecond X-ray pulses, opening new opportunities to leverage the abundance of data in combination with advances in machine learning (ML) to better align the x-ray source with specific experimental goals. We approach the challenge from both ends of the facility. Starting at the X-ray output, we showcase our low latency, high...
Local coupling correction in Interaction Regions (IRs) and global coupling correction based on Base-Band Tune (BBQ) measurement have been performed routinely for RHIC operation. However, one still observes significant residual local coupling measured by beam position data. For the Electron-Ion Collider (EIC) project, betatron decoupling for the hadron beam needs to be improved to maintain a...
Operation with ultra-low momentum-compaction factor (alpha) is a desirable capability for many storage rings and synchrotron radiation sources. For example, low-alpha lattices are commonly used to produce picosecond bunches for the generation of coherent THz radiation and are the basis of a number of conceptual designs for EUV generation via steady-state microbunching (SSMB). Achieving...
The luminosity of particle colliders depends, among other parameters, on the transverse profiles of the colliding beams. At the LHC at CERN, heavy-tailed transverse beam distributions are typically observed in routine operation. The luminosity is usually modelled with the assumption that the 𝑥-𝑦 planes are independent (i.e. statistically uncorrelated particle distributions between the planes)...
For the 2024 100 GeV proton run at RHIC, the new sPHENIX detector will require a maximum amount of collisions within ±10 cm of its central Interaction Point (IP), and preferably few or no collisions outside this range. To maximize the collisions within the vertex, a large crossing angle of up to 2 mrad will be used, operating the Large Piwinski Angle (LPA) scheme. To compensate for the...
Laser, MPS, Modulator, Vacuum, LLRF, etc. are installed at the Pohang Accelerator Laboratory-XFEL linac section. Each device must be protected against emergency situations. When an interlock signal occurs in the XFEL linac section of Pohang Accelerator Research Institute, the beam shutter is closed using the PLC and the operation of each device is blocked. We used an Emerson PLC and connected...
The peak-detected Schottky system is a powerful diagnostic tool for observing the longitudinal beam parameters. According to the theoretical model, the peak value of the signal from a wide-band pick-up contains information on particle distribution as a function of the synchrotron frequency. Due to intrinsic assumptions needed for modelling the acquisition set-up and uncertainties in beam...
We present a beam-focusing architecture using electro- and permanent magnets for a novel compact electron beam buncher under development for space-borne electron accelerators. Developing compact and efficient accelerator components has become desirable with renewed interest in using space-borne electron beams for ionospheric aurora research and very low frequency wave generation for particle...
Compact free electron laser (FEL) technology enabled by plasma-based accelerators is rapidly maturing with several milestone demonstrations in the last 2-3 years. Still, critical work is needed to bridge the gap from proof of concept experiments to reliable operation of plasma-based FELs. At the BELLA Center, we have a laser plasma accelerator (LPA) beamline equipped with an electron beam...
Understanding and optimizing the electron cooling performance is essential to ensure high-brightness antiproton beams at the Extra Low Energy Antiproton (ELENA) ring at CERN. This paper presents measurements and simulations of the electron cooling performance in ELENA. The simulations are obtained using the Parkhomchuk model for electron cooling recently implemented in the Xsuite simulation...
As a part of the High Energy upgrade to the Linac Coherent Light Source II at SLAC, LBNL is responsible for the update of the undulators of the Soft X-Ray (SXR) line. In order to span the required photon energy range, the SXR undulators require longer magnetic period. This increased magnetic period leads to higher magnetic force, requiring updates to certain elements of the design. In...
Two distinct crab cavities are planned to compensate the luminosity loss of the 25 mrad crossing angle at the Electron Ion Collider (EIC) interaction point. The crab cavity systems being developed will operate at either 197 MHz or 394 MHz and the 197 MHz system will provide up to 11.5 MV of transverse voltage with up to 60 kW of fundamental mode power with a coaxial coupler. The 197 MHz crab...
Microbunching instability (MBI) has been an important issue in the design of advanced x-ray free-electron lasers. We have performed theoretical and simulation analyses of MBI for the transport in the beam switchyard system, including the effects of different initial beam parameters. In addition, a comparison is given for different beam switchyard section designs.
Previous start-to-end simulations of an emittance exchange (EEX)-based photoinjector have demonstrated highly attractive beam properties. The EEX-based photoinjector can provide another interesting opportunity that potentially eliminate the microbunching instability issue. The space-charge and/or CSR-induced amplification occurs during density-to-energy and energy-to-density modulation...
Two parallel corrugated plates can be used to manipulate the impedance of an electron storage ring such as the KIT storage ring KARA (KArlsruhe Research Accelerator). This impedance manipulation structure opens up the possibility to eventually control the electron beam dynamics and the emitted coherent synchrotron radiation (CSR). In this contribution, we present the impedance that is most...
High Harmonic Generation (HHG) has been a brilliant and successful technique for the generation of natural mode-locked attosecond laser pulses in the VUV regime. It’s promising to employ the HHG laser as an external seed in a harmonic-generation FEL facility for the generation of high power short wavelength mode-locked FEL pulses. In this paper we propose a method to try to make this happen....
Linear particle accelerators are elaborate machines that demand a thorough comprehension of their beam physics interactions to enhance performance. Traditionally, physics simulations model the physics interactions inside a machine but they are computationally intensive. A novel solution to the long runtimes of physics simulations is replacing the intensive computations with a machine learning...
The model of spin depolarization invoking isolated resonances hinges on a closed-form solution of energy ramping with the Single Resonance Model by Froissart and Stora. However, for non-resonant orbital tunes, resonant depolarization by single resonance crossing is impossible in the SRM while using a pair of Siberian Snakes since the amplitude-dependent spin tune is then fixed to one-half....
The TopGun photoinjector is a 1.6-cell C-band gun developed by the University of California, Los Angeles team. Originally optimized for 100 pC operation, its low emittance design has been our starting point. However, the Los Alamos National Laboratory (LANL) needs to operate with a 250 pC bunch charge while maintaining an emittance below 100 nm. The initial optimization of the high charge...
This work aims to improve the ability of particle accelerator researchers to develop high-performance accelerator cavity designs by creating an overall multiphysics framework that integrates and couples existing application codes. This framework will allow accelerator researchers to build multiphysics models that will optimize cavity design, improve understanding of whole-device performance,...
Many reactor-based neutron sources are planned to shut down in the near future, and this is despite the increasing demand for neutron beamlines for a wide range of scientific and industrial applications. Consequently, compact accelerator-based neutron sources arise as a competitive alternative that could meet the need for medium-flux fission or spallation sources. In this work, we explore the...
At Varex Imaging Corporation, we have started a transition to our in-house supply of Accelerator Beam Centerlines (ABC), replacing Varian as a supplier. As part of this program we are considering changing design of our K-15, the only standard production unit capable of delivering Bremsstrahlung at 12000 R/min@1m by striking a copper target with high energy electron beam at 15 MeV. We plan on...
The FLASH facility is currently undergoing a transformation to generate FEL radiation suitable for next generation user experiments. Here, the transition of FLASH1 from a SASE to an externally seeded FEL beamline is in main focus and will significantly expand the facilities capabilities. Near transform limited pulses at superior spectral and energy stability at full FLASH repetition rate of 1...
The beam transverse emittances play a critical role in high-energy colliders. Various measurement techniques are employed to measure them. In particular, the so-called luminosity emittance scans (or Van der Meer scans) are used in order to evaluate the convoluted beam emittances. This method assumes different emittances in the two planes but identical emittances in the two beams. In this...
In high-gain free-electron lasers (FELs) with planar undulators it is possible (in the linear regime) to independently amplify at the fundamental and at odd harmonics, a process referred to as Harmonic Lasing (HL). For the HL process preservation of the quality of the incoming high-brightness electron beam is essential. This requires suppression of the lasing at the fundamental, which can be...
Following the decommissioning of the Main Injector Neutrino Oscillation Search (MINOS) experiment, muon and hadron monitors have emerged as essential diagnostic tools for the NuMI Off-axis nu_mu Appearance (NOvA) experiment at Fermilab. For this study, we use a combination of muon monitor simulation and measurement data to study the monitor responses to variations in proton beam and lattice...
Charged-particle beams with intense longitudinal fields in accelerating structures inevitably couple to transverse modes, potentially causing beam break-up instability. To maintain beam quality in applications like linear colliders, addressing this coupling is crucial. Flat-beams, featuring highly asymmetric transverse sizes, can delay the initial instability in slab-symmetric structures....
In 2023 the LHC restarted after the yearly winter shutdown with a new machine configuration optimized for intensities of up to 1.8e+11 protons per bunch. In the first two months of the 2023 run the bunch intensities were pushed up to 1.6e+11 protons per bunch until a severe vacuum degradation, caused by a damaged RF bridge, occurred close to the ATLAS experiment. Following repair, the decision...
The favorable wavelength scaling of ponderomotive interactions indicates that long-wave infrared (LWIR) lasers are well suited for applications such as laser wakefield acceleration and high harmonic generation. CO2 amplifiers are the primary source of such wavelengths, able to generate TW peak powers with sub-ps pulse lengths. However, a limiting factor for these amplifiers is the necessity of...
To maintain beam emittance and quality, particle beams in plasma wakefield accelerators (PWFAs) need to be focused to extremely small sizes upon entering the accelerator. Conventional methods that achieve this involve large quadrupole electromagnets, which can occupy a considerable amount of space, often spanning several meters. The plasma lens, however, represents a compact, strong...
Measuring the composition and content of dissolved substances in aqueous solutions is in demand in fields such as biomedicine, and industrial production. The material analysis technique based on thermal neutron capture reaction is one of the commonly used methods for analyzing the composition and content of dissolved substances in aqueous solutions. The material analysis technology based on...
The injector section of the SHINE device is currently in the debugging phase. The electron beam energy in the injector section is low and is significantly affected by the geomagnetic field, with an intensity of approximately 250 milligauss. Through theoretical optimization, adjustments to the positions and intensity parameters of helical coils and corrector magnets are being made to...
ELSA LINCS (ELSA Linac INverse Compton Source) at CEA DAM DIF is an Inverse Compton Scattering X-ray source in the 5-40 keV range, through interaction between 10-30 MeV electrons with a Nd:YAG laser. The source was upgraded to increase the X-ray flux produced in the 5-40 keV range. The new experimental setup and imaging systems have been modified for compatibility with fundamental emission at...
Laser-plasma accelerators (LPAs) can have high acceleration gradients on the order of 100 GeV/m. The high acceleration gradients of LPAs offer the possibility of powering future colliders at the TeV range and reducing the size of particle accelerators at present energy levels. LPAs need tightly focused, high intensity laser pulses and require guiding structures to maintain the laser focus over...
Plasma-based particle accelerators maintain accelerating fields that are several orders of magnitude higher than conventional accelerators. This allows for more compact accelerator footprints that can deliver particle beams of very high charge (> 100 pC) and large current (> kA) for various applications. Plasma-wakefield accelerators are promising candidates for next-generation TeV-class...
For the Recycler Ring at Fermilab, space charge tune shifts of almost 0.1 will have to be dealt with under the Proton Improvement Plan (PIP-II) framework. This will lead to the excitation of third order resonances. The minimization of Resonance Driving Terms (RDTs) allows to mitigate the harmful effect of these betatron resonances. Past work has shown that previously-installed sextupoles can...
Scientific opportunities with very hard XFEL radiation demands dedicated facility development towards FEL operation in the sub-ångström regime. Very hard X-rays provide capabilities of high Q-range coverage and high penetration, and also allow access to the K-edge spectroscopy of high-z materials. Production of such X-rays using FELs takes advantage of general FEL characteristics such as large...
The interactions of charged particles with carbon nanotubes (CNTs) may excite electromagnetic modes in the electron gas that makes up the nanotube surface. This novel effect has recently been proposed as an alternative method to achieve ultra-high gradients for particle acceleration. In this contribution, the excitations produced by a localized point-like charge propagating in a single wall...
An analytical form is derived using the Faddeeva function to represent terahertz-frequency pulses generated by optical rectification of ultrashort laser pulses. Spectra of these pulses can be described by a Gaussian fall-off at high frequencies and a power-law as DC is approached. A set of pulsed beams based on this form is also derived for the special case of propagation-invariant...
Coherent synchrotron radiation (CSR) induced microbunching instability (MBI) has been an issue in the multi-bend design for a single-pass high-brightness electron beam transport. Recently a novel design of a non-symmetric four-dipole bunch compressor chicane has been proposed to effectively mitigate the CSR-induced emittance growth, compared with the symmetric C-type chicane widely used in...
Numerical modeling of low-temperature plasma (LTP) ion sources provides cost-effective techniques for developing and optimizing beam characteristics for ion implantation and other applications, including plasma processing and etching. Particle-in-cell (PIC) models are a powerful tool for simulating plasma formation and dynamics in LTP sources. Beam formation and transport of the beam through...
Single-spoke resonators (SSRs) have been developed and tested for the RAON SCL2 project. The design pa-rameters for the SSRs are provided, and the performance of the superconducting cavities is assessed. The single-spoke resonator cavities, cryogenic systems, cryostats, and human machine interface (HMI) are depicted for a vertical test. Calibration and cavity preparations are demonstrated to...
We are presenting a design of a 2-18 GeV electron synchrotron accelerator made of permanent non-linear combined function magnets with fixed betatron tunes. It is based on the successfully commissioned CBETA Energy Recovery Linac where we used a single return beam line based on Fixed Field Alternating gradient (FFA) principle. The 2 GeV injection energy electrons come from the Recirculating...
High-efficiency alkali antimonide photocathodes degrade with little oxidation, making them hard to characterize and test outside their growth chamber. In this proceeding, we report on the design and performance of the PHOtocathode Epitaxy and Beam Experiments (PHOEBE) laboratory at Cornell University, where the growth, characterization, and testing of alkali photocathodes in vacuum has been...
The plasma accelerator-based Free Electron Laser research program at ELI-ERIC (ELI-Beamlines, Czech Republic) intends to utilize the unique qualities of plasma accelerators to build FELs with remarkable brightness, coherence, and pulse length. The program is based on the novel high-power, high-repetition-rate laser system, which is under preparation at ELI-Beamlines. The program entails...
We study the design and spin performance of a polarized electron Booster. This booster will accelerate polarized electrons from 200 MeV to 3 GeV. We examine the polarization transmission of the existing NSLS-II Booster design as well as a modified AGS-Booster lattice using an 8-fold symmetric design and increasing the betatron tune to 7.85 to avoid all intrinsic spin resonances.
The Electron Storage Ring (ESR) of the Electron-Ion Collider (EIC) to be built at Brookhaven National Laboratory will provide spin-polarized electron beams at 5, 10, and 18 GeV for collisions with polarized hadrons. Electron bunches with polarizations parallel and anti-parallel to the arc dipole fields will co-circulate in the ring at the same time, and each bunch must be replaced once it is...
PolFEL, the Polish Free Electron Laser facility, after recent configuration adjustments, will feature a dual superconducting electron linac fed in the first stage by pulse-operating, made of copper photoinjectors. In the second stage, both Cu injectors will be replaced by superconducting injectors enabling the cw operation. The first linac line equipped with two Rossendorf-RI type cryomodules...
High field radio frequency (RF) accelerating structures are an essential component of modern linear accelerators (linacs) with applications in photon production and ultrafast electron diffraction. Most advanced designs favor compact, high shunt impedance structures in order to minimize the size and cost of the machines as well as the power consumption. However, breakdown phenomena constitute...
The Advanced Wakefield Experiment (AWAKE) aims
to accelerate electrons to particle physics relevant energies
using self-modulated proton bunches as drivers in a single
plasma. AWAKE is now in its Run 2b (2023-2024), where
the goal is to stabilise wakefields by using a plasma density step. Experimental demonstrations require probing of the longitudinal wakefields by externally injected...
SLAC has developed the parallel finite element electromagnetics simulation suite ACE3P which employs the parallel high-order finite element (FE) method to solve Maxwell's equations at the macroscopic level. Under the support of an SLAC LDRD, optical nonlinearities in the transient regime have been incorporated into the ACE3P time-domain solver for the investigation of nonlinear physical...
Previously we had developed a new method to fabricate corrugated waveguides (CW) operating in sub-THz frequency regime. As the next step, collaborative effort is underway to demonstrate GW-level high-power sub-THz pulse generation using a CW. We plan to fabricate a CW operating at around 400 GHz. This waveguide will be driven by a bunch train including 16 bunches with nanocoulomb-level charges...
At UCLA, a plasma source using capillary discharge has been developed and studied for its potential use in plasma wakefield experiments at MITHRA and AWA facilities. This compact, 8-cm long source, has the ability to create plasmas covering a wide range of densities, making it suitable for various experiments involving plasma wakefield acceleration (PWFA). With a 3-mm aperture, it can transmit...
We present an update on the design of the Interaction Region (IR) for the the Electron Ion Collider (EIC) being built at Brookhaven National Laboratory (BNL). The EIC will collide high energy and highly polarized hadron and electron beams with a center of mass energy up to 140 GeV with luminosities of up to 10^34 /cm^2/s. The IR, located at RHIC's IR6, is designed to meet the requirements of...
Plasma-wakefield acceleration represents an exciting route towards reducing the footprint of future high-energy electron accelerators by accelerating bunches in fields exceeding 1 GV/m. One such technique employs a double-bunch structure where the trailing bunch is accelerated in the field of a high-amplitude plasma-density wake driven by the leading bunch. A future particle collider or photon...
The longitudinal compression of intense proton bunches with strong space-charge force is an essential component of a proton-based muon source for a muon collider. This paper discusses a proton-bunch compression experiment at the Integrable Optics Test Accelerator (IOTA) storage ring at Fermilab to explore optimal radio frequency (RF) cavity and lattice configurations. IOTA is a compact...
In December 2021, damage to a couple of RHIC power supplies forced
one of two Siberian Snakes in the Blue ring to operate as a partial Siberian
Snake and with a different snake axis of rotation. The time-averaged polarization for that run actually ended up higher than in the Yellow ring, after
casting the undamaged snake as a partial snake as well. In this work,
we simulate...
For certain photonuclear experiments utilizing Compton gamma-ray beams, beam-uncorrelated background poses a significant challenge. At the High Intensity Gamma-ray Source (HIGS), we have developed methods to generate pulsed free-electron laser (FEL) beams by transversely or longitudinally modulating the storage ring FEL. Both methods enable periods of FEL interaction: one by transversely...
Studying the energy deposition in accelerator components, mechanical supports, services, ancillary equipment and shielding requires a detailed computer readable description of the component geometry. The creation of geometries is a significant bottleneck in producing complete simulation models and reducing the effort required will allow non-experts to simulate the effects of beam losses on...
FLUKA simulations of beamlines are important for understanding numerous different aspects of accelerators, including beam losses, particle backgrounds, activation and shielding. Creating a beamline simulation using FLUKA is a time consuming and potentially error prone process. This paper describes a set of python tools called pyflubl (Python FLUKA beamline) which can create a FLUKA simulation...
Dielectric Wakefield Acceleration is a technology under active research, providing the potential to accelerate charged particle bunches with gradients much greater than conventional RF-based metallic cavities. The stability of driving bunches needs to be solved before practical applications are seen. Strong transverse fields are known to be excited in DWAs, with previous research focusing on...
Superlattice GaAs photocathodes play a crucial role as the primary source of polarized electrons in various accelerator facilities, including the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson National Laboratory and the Electron-Ion Collider (EIC) at Brookhaven National Laboratory. To increase the quantum efficiency (QE) of GaAs/GaAsP superlattice photocathodes, a...
For the development of X-band deflecting structure at Shanghai Synchrotron Radiation Facility (SSRF), two units of X-band deflecting structures totally including six RF structures have been used on SXFEL successfully for ultra-fast beam diagnostics. The construction of another new FEL facility has started from 2018, which is named Shanghai high repetition rate XFEL and extreme light facility...
The Accelerator Test Facility (ATF) at Brookhaven National Laboratory is a DOE Office of Science User Facility supported by the DOE Office of Accelerator R&D and Production. It provides its users with 3 major beam capabilities: 75 MeV high brightness electron beams, multi-terawatt long-wave infrared (LWIR) laser beams, and near infrared (NIR) laser beams. These capabilities can be used...
The Electron Storage Ring (ESR) of the Electron-Ion Collider requires some 400 quadrupoles and 200 sextupoles, plus dipole magnets and correctors. In an effort to reduce cost and relax the demand on the magnet vendor pool, used quadrupoles and sextupoles of the Advanced Photon Source at Argonne National Laboratory will be refurbished and installed in the ESR.
The newly commissioned CYBORG (CrYogenic Brightness Optimized Radiofrequency Gun) beamline at UCLA operates in a high gradient, low temperature regime inaccessible to most other existing photoguns and cathode testing infrastructure. The beamline is designed to study electron emission in regime. The final intended configuration of the beamline will be used for studies of novel photocathodes...
Semi-deterministic optimization problems are common in operating complex lasers and accelerator facilities. In these problems, a few optimal solutions exist that can achieve satisfactory system performance for a specific system state. Typically, online optimizations are performed to find these optimal solutions, which can be time-consuming and must be repeated when the system state changes. In...
CLAPA-II, a novel proton therapy accelerator under development at Peking University and supported by the Ministry of Science and Technology of China, utilizes chromatic aberration and dispersion effects for energy selection of the laser proton beam driven by the radiation pressure acceleration (RPA). Through comprehensive research of the energy selection system using TraceWin, CLAPA-II can...
The utilization of laser modulation techniques shows potential in producing sub-femtosecond electron beams within photoinjector electron guns. The precise spatial alignment between the modulated laser and electron beam is crucial for the stable emission of sub-femtosecond electron beams. In practical applications, inevitable lateral positional fluctuations are present in both the modulated...
The Electron-Ion Collider (EIC) utilizes the existing Relativistic Heavy Ion Collider (RHIC) rings as a Hadron Storage Ring (HSR) with some modifications. However, this presents significant challenges, primarily due to beam-induced Resistive Wall (RW) heating resulting from a larger radial offset and shorter EIC bunches (up to 10 times shorter than RHIC). Additionally, the formation of an...
The CERN Proton Synchrotron Booster (PSB) operation involves the crossing of multiple resonance lines in the tune diagram. Loss maps from dynamic tune scans are a helpful way to visualize and quantify the strength of such resonances. Sextupole and octupole correctors can be used in order to partially or fully compensate multiple resonance lines, i.e., third and fourth order lines. The...
This talk summarizes the plans, challenges and key components of the four phases in the AWAKE roadmap. In addition, an overview of the rich measurement program of the second phase, AWAKE Run 2b, during 2023 and 2024 is given. Results from a unique 3-week measurement opportunity with a 10m discharge plasma source prototype are shown, including the effects of different gases, plasma densities,...
The Relativistic Heavy Ion Collider (RHIC) Run 23 program consisted of collisions of 100 GeV gold beams at two collision points for the first time since 2016; the sPHENIX collaboration used the beam to commission their new detector systems while STAR took physics data. Completion of sPHENIX construction pushed the start of the run to May, forcing the collider complex to operate over the summer...
The Fritz-Haber-Institut (FHI) der Max-Planck-Gesellschaft Free Electron Laser (FEL) achieved first light from its Mid-IR beamline at 18 microns on February 14, 2012. In the subsequent years, the 3 to 60 micron light has been supplied to users resulting in 96 refereed publications in Chemical Physics. In 2019, the FEL Group initiated an upgrade to add a Far-IR beamline to the system. On June...
During 2023, examination of the action dependence of sextupolar resonance driving terms (RDT) in the LHC at injection, as measured with an AC-dipole, demonstrated that a robust measurement of the RDTs could still be achieved even with very small amplitude kicks, typically used for linear optics studies. Consequently, analysis of optics measurements from 2022 and 2023 during the LHC energy ramp...
In the High Luminosity Large Hadron Collider (HL-LHC) era, the intensity of the circulating bunches will increase to 2.2e+11 protons per bunch, almost twice the nominal LHC value. Besides detailed studies of known and new failure cases for HL-LHC, it is also required to investigate failures beyond nominal design. A consequence of such failures can be the impact of a large number of high-energy...
Laser wakefield accelerators (LWFAs) are capable of supporting accelerating and focusing forces on the order of 10–100 GeV/m, about three orders of magnitude greater than conventional RF accelerators. While theoretical solutions for the electromagnetic (EM) focusing fields have been developed, the field structures have yet to be verified experimentally. In this poster, we present simulation...
The CXFEL project at ASU will produce coherent soft x-ray radiation at a university-scale facility. Unlike conventional XFELs, the CXFEL will use an optical undulator in addition to nanobunching the electron beam instead of a static magnetic undulator. This reduces the undulator period from cm-scale to micron scale and lowers the requirements on the electron beam energy. CXFEL’s overtaking...
The proof-of-principle (PoP) experiment at the Super Proton Synchrotron (SPS) at CERN aims at demonstrating laser cooling of high energy Li-like Pb79+ in a synchrotron. First laser cooling simulations with realistic laser and beam parameters of the Gamma Factory proof-of-principle experiment (PoP) in the Super Proton Synchrotron (SPS) at CERN are presented. Furthermore, we investigate the...
Laser wakefield acceleration (LWFA) has been highlighted in the development of table-top accelerators and compact light sources. However, the stability issues on beam quality and pointing remain unsolved problems. Many groups apply the technique of ionization injection for higher charge with the narrower energy spread into a supersonic gas jet target or a capillary discharge system. The LWFA...
Generating nanometer-scale density modulation has been pursued due to its potential for compact X-ray source applications. Realization of this nanometer modulation involves two key challenges: development of sub-micron-scale momentum modulation method and conversion method to density modulation without quality degradation. Addressing the first challenge, emittance exchange (EEX) beamline is a...
Dynamic Aperture (DA) studies, based on single-particle tracking simulations including important non-linear fields such as beam-beam effects, have played a crucial role in guiding the operation of the Large Hadron Collider (LHC) in proton-proton collisions. The correspondence between DA computed through simulations and the actual beam lifetime during operation has been established for proton...
The first operational high peak and average power THz self-amplified spontaneous emission (SASE) free electron laser (FEL) at the Photo Injector Test facility at DESY in Zeuthen (PITZ) has demonstrated up to 100 uj single pulse energy at a center frequency of 3 THz from electron bunches of 2-3 nC. The measured shot-to-shot radiation pulse energy has a fluctuation of 10%. Shot-to-shot...
We present an initial capture concept for the continuous wave (CW) polarized positron beam at the Continuous Electron Beam Accelerator Facility (CEBAF) upgrade at Jefferson Lab. This two-step concept is based on (1) the generation of bremsstrahlung radiation by a longitudinally polarized electron beam (1 mA, 120 MeV, >90% polarization), passing through a tungsten target, and (2) the production...
We present a Fixed-Field-Alternating (FFA) permanent magnet racetrack electron accelerator with energy range between 10-60 GeV for the future LHeC. Electron beam is brought back to the linac by the single beam line without requiring electric power REDUCING estimated wall power of 100 MW in the present LHeC design to a negligible power for arcs as the permanent magnets are used. The design is...
Diamond-II is a future 4-th generation synchrotron light source with a significantly narrower vacuum chamber compared to the existing Diamond storage ring. The strength of wake fields will increase, and, consequently, the risk of single-bunch instabilities also rises. We consider chromaticity adjustment and a passive harmonic cavity as mitigation measures, including for cases with impedance...
Recent studies have investigated a longitudinal instability that may develop in electron storage rings featuring higher-harmonic cavities. The instability, also referred to as periodic transient beam loading (PTBL), manifests as a slow oscillation of bunch longitudinal profiles following a coupled-bunch mode 1 pattern. In this contribution, we applied a well-established theory of longitudinal...
The 2D Orszag-Tang vortex magnetohydrodynamics (MHD) problem is studied through the use of physics-constrained convolutional neural networks (PCNNs). The density and the magnetic field are forecasted, and we also predict magnetic field given the velocity field of the fluid. We examined the incorporation of various physics constraints into the PCNNs: absence of magnetic monopoles,...
In free-electron lasers seeded by a coherent pulse, the term superradiance refers to a regime in which the seed pulse is consistently shortened by a slippage-dominated interaction with the electron beam. This regime is extremely promising for attosecond X-ray free-electron lasers in particular, as it offers a potential path towards shorter, higher power pulses. We study the practical limits of...
In collinear wakefield acceleration, two figures of merits, gradient and transformer ratio, play pivotal roles. A high-gradient acceleration requires a high-charge beam. However, shaping current profile of such high-charge beam is challenging, due to the degradation by CSR. Recently proposed method, utilizing transverse deflecting cavities (TDC) for shaping, has shown promising simulation...
A second hard X-ray beamline (HX2) at the PAL-XFEL (Pohang Accelerator Laboratory, X-ray Free Electron Laser) has been proposed to meet the increased demands of XFEL science. A photon energy ranging between 1.5 to 10 keV was determined to cover low photon energy with enhanced FEL pulse energy of about 3.0 mJ, and to cover mostly used range between 8 to 10 keV simultaneously. Accordingly,...
The microbunching instability (MBI) driven by beam collective effects can cause significant electron beam quality degradation in advanced X-ray free electron lasers. Typically, multiple stage magnetic bunch compressors used to generate high peak current electron beam will dramatically amplify the microbunching instability. In this paper, by redesigning the solenoid elaborately and adopting a...
Cavity-based X-ray free electron laser (CBXFEL) is the proposed scheme to dramatically improve stability and coherence of the existing XFELs. A project to demonstrate proof-or-principle CBXFEL is underway at SLAC National Accelerator Laboratory, in collaboration with Argonne National Lab (ANL, USA) and RIKEN Research Institute (Japan). CBXFEL is expected to operate at 9.831 keV photon energy,...
Laser-plasma accelerators (LPAs) have potential to enable compact light sources and high-energy linear colliders. At the BErkeley Lab Laser Accelerator (BELLA) PW facility, electron bunches with energy up to 8 GeV have been generated using laser pulses with peak power of 0.85 PW (energy 31 J) and an acceleration length of 20 cm. In order to accelerate over this distance of 15 diffraction...
The status of commissioning of the electron injector intended for the next phase of the proton driven wakefield experiment (AWAKE) is presented, showing first experimental results from operating the brazing-free electron gun. To provide a high-quality electron beam, the UV laser was centered on the copper cathode, and a novel simplex and beam-based alignment of the focusing solenoid was...
Provisions are being made in the Electron Ion Collider (EIC) design for future installation of a second Interaction Region (IR), in addition to the day-one primary IR. The envisioned location for the second IR is the existing experimental hall at RHIC IP8. It is designed to work with the same beam energy combinations as the first IR, covering a full range of the center-of-mass energy of ~20...
In the framework of the FLASH2020+ project, the FLASH1 beamline will be upgraded to deliver seeded FEL pulses for users. This upgrade will be achieved by combining high gain harmonic generation and echo-enabled harmonic generation with a wide-range wavelength-tunable seed laser, to efficiently cover the 60-4 nm wavelength range. The undulator chain will also be refurbished entirely using new...
The SASE3 Variable Polarization project is intended to offer polarization control of the X-ray FEL pulses at the European XFEL. The project was completed in early 2022. During the winter shutdown 2021-2022, all four APPLE-X helical undulators were placed in the tunnel and first lasing was achieved in April 2022. Unfortunately, further use of the helical afterburner proved impossible, as the...
A program is underway at the Argonne Wakefield Accelerator (AWA) facility, in collaboration with Euclid Techlabs and Northern Illinois University (NIU), to develop a GV/m-scale photocathode gun, to produce bright electron bunches. The novel X-band (11.7 GHz) photoemission gun (Xgun) is powered by high-power, short RF pulses (9 ns) generated by the AWA drive beam in a wakefield structure. In...
The space-charge neutralization of an ion beam by created electrons when the beam ionizes the gas is investigated using a three-dimensional electrostatic particle-in-cell code. Different kinds of injected gases are considered, and their space-charge compensation transient times are compared. The created secondary electrons by the beam collision with neutral gas along the beam trajectories are...
Using a simplified multi spin resonances model we study the how the interference of spin resonances near a strong intrinsic spin resonance crossing effect the polarization transmission as a function of emittance for a lattice with more than two snakes.
Synchrotron radiation could contribute to detector background significantly, especially when the electron beam deviates from the design orbit. Without effective control, synchrotron radiation could impede physics data taking or even damage detector components. One of the key contributors to suppress synchrotron radiation in the Electron-Ion Collider IR is to control the electron orbit upstream...
A new layout for the energy-frontier hadron collider (FCC-hh) under study at CERN has been designed, following the constraints imposed by the outcome of recent tunnel placement studies. The new lattice and the need to maximize the dipole filling factor triggered a deep revision of the corrector systems located in the regular arcs, such as orbit, tune, linear coupling, and chromaticity...
A new infrared Free-Electron Laser (FEL) facility FELiChEM has been established as an experimental facility at the University of Science and Technology of China. It consists of two free electron laser oscillators which produce mid-infrared and far-infrared lasers covering the spectral range of 2-200 μm at the present stage. The output power is a crucial parameter for users, and it is usually...
Manipulation electron beam phase space technology by laser-electron interaction has been widely used in accelerator-based light sources. The energy of the electron beam can be modulated effectively under resonant conditions by using an intense external laser beam incident into the undulator together with the electron beam.
Enhancing the modulation efficiency is crucial for the performance of...
The soliton-like superradiant regime in a free-electron laser is a fully non-linear phenomenon in which the bandwidth of a short pulse can be coherently broadened as the pulse is amplified. As such, superradiance has long been considered a promising route towards high-power ultrashort pulses exceeding the natural bandwidth of high-gain FELs. This regime has now been observed in several...
The Advanced Light Source Upgrade (ALS-U) is a 2 GeV high-brightness, nine-bend achromat storage ring, designed to reduce the natural emittance relative to the existing ALS by a factor of 20 for improved x-ray coherent flux and brightness. The upgrade includes the installation of an accumulator ring of the same energy as, and slightly smaller circumference than, the storage ring. The bending...
High-power attosecond X-ray pulses are ideal probes of ultrafast nonlinear interactions in quantum systems. We demonstrate the production of soft X-ray pulses with terawatt-scale peak powers and few hundred attosecond pulse durations in a two-stage cascaded X-ray free-electron laser. We diagnose the pulse properties in the time domain with angular streaking. Our results exceed the peak power...
Metamaterial accelerators driven by nanosecond-long RF pulses show promise to mitigate RF breakdown. Recent high-power tests at the Argonne Wakefield Accelerator (AWA) with an X-band metamaterial structure have demonstrated to achieve a gradient of 190 MV/m, while we also observed a new acceleration regime, the breakdown-insensitive acceleration regime (BIAR), where the RF breakdown may not...
The CXFEL is designed to produce attosecond-femtosecond pulses of soft X-rays in the range 300-2500 eV using nanobunched electron beams and a very high power laser undulator. The project includes 5 X-ray endstations with applications in biology, quantum materials, and AMO science. The CXFEL Project overall includes both the CXFEL and the nonlasing hard X-ray CXLS that is described elsewhere in...
The polarized pre-injector for the Electron-Ion Collider is intended to produce four bunches every second, each containing 7 nC, with 85% polarization along the longitudinal axis, for injection into the Rapid Cycling Synchrotron. The pre-injector consists of a polarized electron source, bunching section, longitudinal phase space manipulation, and SLC-Type LINAC. To reduce energy spread and...
The design of the electron-ion collider (EIC) at Brookhaven National Laboratory is well underway, aiming at a peak electron-proton luminosity of 10e+34 cm^-1·sec^-1. This high luminosity, the wide center-of-mass energy range from 29 to 141 GeV (e-p) and the high level of polarization require innovative solutions to maximize the performance of the machine, which makes the EIC one of the most...
The hadron storage ring (HSR) of the Electron-Ion Collider (EIC) is a modification of the RHIC for acceleration and collision of protons and ions. The 6 straights in RHIC will be modified, and the 6 arcs will be left in place. There are four geometric configurations, switching one arc depending upon the energy of the hadrons or ions, and with two different configurations for one straight,...
Wigglers are periodic arrays of magnets with myriad applications in accelerator physics. Generally though, they are only tunable by adjusting the gap between jaws. Here, we present a wiggler based on diametrically magnetized cylindrical magnets with independently adjustable angle. This allows the realization of arbitrary (bandwidth constrained) magnetic configurations. We illustrate its...
The UK XFEL project is now mid-way through its three-year Conceptual Design and Options Analysis (CDOA) phase. The purpose of this phase is to develop concepts to meet the required ‘next-generation’ XFEL capabilities identified in the project’s peer-reviewed Science Case, developed by UK scientists. The envisaged next-generation features are a step-change in both the number of simultaneous...
An x-ray free-electron laser oscillator (XFELO) is a promising candidate for producing fully coherent x-rays beyond the fourth-generation light sources. An R&D XFELO experiment (ANL-SLAC-Spring-8 collaboration) to demonstrate the basic principles and measure the two-pass FEL gain is expected to be accomplished by 2024. Beyond this R&D experiment, an XFELO user facility will be eventually...
The addition of spin-polarized, continuous-wave (c.w.) positron beams to the 12 GeV Continuous Electron Beam Accelerator Facility (CEBAF) would provide a significant capability to the experimental nuclear physics program at Jefferson Lab. Based on bremsstrahlung and pair-production in a high-Z target, the positron source requires a 120 MeV spin-polarized c.w. electron beam of several...
We have launched a research program on attosecond X-ray sources utilizing high-harmonic generation (HHG) driven by an infrared free-electron laser (FEL) oscillator. As the results of the first six years of the program, we have improved the FEL performance at KU-FEL and LEBRA-FEL to achieve FEL intensity high enough for HHG. We observed HHG from a solid target and tunnel-ionizing electrons in...
We report on the status of a degrader device to generate large phase space beams for machine acceptance studies in the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab. The degrader device consists of thin, low-Z targets to degrade the electron beam phase space through multiple scattering, two apertures to define the maximum transverse emittance, and a solenoid to aid in...
Addressing the charged particle beam diagnostics in accelerators poses a formidable challenge, demanding high-fidelity simulations in limited computational time. Machine learning (ML) based surrogate models have emerged as a promising tool for non-invasive charged particle beam diagnostics. Trained ML models can make predictions much faster than computationally expensive physics simulations....
The FLARE project aims to investigate special operation modes of the laser heater at the free-electron laser FLASH in Hamburg that enable the generation of few- or possibly sub-femtosecond soft X-ray pulses. To this end, laser pulses of the laser heater are split and then recombined after one pulse has been delayed. By controlling the interference of both pulses via their temporal overlap, a...
Beam lengthening is an effective and commonly used method to improving the beamlife of storage rings. Based on the previously proposed design of a room temperature conducting bimodal RF cavity, we conducted relevant dynamic simulations. Tracking study on a simulated storage ring lattice with the beam energy of 2 GeV and the synchronous radiation energy of 357 KeV, the results show that, the...
The Continuous Electron Beam Accelerator Facility (CEBAF) operates hundreds of superconducting radio frequency (SRF) cavities in its two linear accelerators (linacs). Field emission (FE) is an ongoing operational challenge in higher gradient SRF cavities. FE generates high levels of neutron and gamma radiation leading to damaged accelerator hardware and a radiation hazard environment. During...
Laser-driven ion accelerators (LDIAs) are well-suited for radiobiological research on ultra-high dose rate effects due to their high intensity. For this application, a transport system is required to deliver the desired beam intensity and dose distribution while online dosimetry is required due to the inherent shot-to-shot variability of LDIAs. At the BELLA Center's iP2 beamline, we...
SOLEIL II is an upgrade project of the existing Synchrotron SOLEIL facility. It aims to reach fourth-generation light source parameters. This includes reductions of the transverse beam emittance, vacuum chamber dimensions and momentum compaction factor. A new impedance model of the SOLEIL II storage ring was developed. This paper demonstrates the evaluation of transverse single- and...
We study coherent transverse beam oscillations in the EIC electron storage ring (ESR), to specify the tolerance for high-frequency ripple of the magnet power supplies. To avoid unacceptable proton emittance growth from the oscillating beam-beam kick from the electrons, the amplitude of these oscillations at the proton betatron frequency needs to be limited to about 1e-4 fraction of the beam...
Plasma temperature dynamics provide significant insight when evaluating ion source performance. Quantities such as beam emittance, or mean transverse energy, are strongly correlated with the source plasma temperature. At LANSCE there is currently no method implemented for measuring initial source emittance or implementing tunability of mean transverse energy through ion source control...
Ultrafast Electron Diffraction (UED) is a pioneering method for real-time observation of atomic-level structures. Recent advancements leverage relativistic electrons from radiofrequency (RF) guns to overcome space charge limitations, enhancing resolution. While perspectives may differ, an ongoing debate surrounds the optimal energy for a UED instrument. Our study contributes to this discussion...
As one of the most important frontiers of international science and technology, the development of ultrafast science has provided important research tools for many disciplines. Free-electron laser (FEL) has the unique advantages of high power and short wavelength in generating ultrafast pulses. In this paper, the theoretical simulations were performed to produce the ultrafast pulses, utilizing...
In this study, we reassess the dynamics within a simple accelerator lattice featuring a single degree of freedom and incorporating a sextupole magnet. In the initial segment, we revisit the H\'enon quadratic map, a representation of a general transformation with quadratic nonlinearity. In the subsequent section, we unveil that a conventional sextupole is essentially a composite structure,...
The aims of the CLARA experiment at the Fermilab Integrable Optics Test Accelerator (IOTA) were to directly measure the coherence length of undulator radiation emitted by a single electron and to test whether the radiation is in a pure classical Glauber coherent state or in a quantum mixture of coherent and Fock states. We used a Mach-Zehnder interferometer (MZI) to study visible radiation...
We develop an alternative theory of coherent synchrotron radiation (CSR) wakefield using the transverse field solution of Maxwell equations in angular domain. This approach allows us to retain only the radiative interaction between particles and cure the frequently encountered divergence in retarded potentials. We analyze the classical radiation reaction force and mass renormalization induced...
Thermionic electron guns that use borides of lanthanum or cerium as the electron emission surface are widely adopted for electron microscopes due to their high brightness. CeB6 cathodes are known for their high environmental durability and can be used up to a vacuum pressure of 1e-6 Pa. At MHI-MS, our company, we also adopt CeB6 cathodes in the C-band compact accelerating structure units we...
One of the challenges of designing the Electron-Ion Collider (EIC) is to mitigate beam-induced heating due to the intense electron and hadron beams. Heating of the Electron Storage Ring (ESR) vacuum chamber components is mainly due to beam-induced resistive wall loss and synchrotron radiation. For the Hadron Storage Ring (HSR) components, heating is mainly due to resistive wall loss because...
Coherent synchrotron radiation has a significant impact on electron storage rings and bunch compressors, inducing energy spread and emittance growth in a bunch. While the physics of the phenomenon is well-understood, numerical calculations are computationally expensive, severally limiting their usage. Here, we explore utilizing neural networks (NNs) to model the 3D wakefields of electrons in...
The spontaneous emission of radiation from relativistic electrons within a plasma channel is called betatron radiation and has great potential to become a compact x-ray source in the future. We present an analysis of the performance of a broad secondary radiation source based on a high-gradient laser-plasma wakefield electron accelerator. The purpose of this study is to assess the possibility...
Powered by a storage ring with energies ranging from 240 MeV to 1.2 GeV, the Duke Free-Electron Laser (FEL) has demonstrated operation across a broad wavelength spectrum from infrared (IR) to vacuum ultraviolet (VUV): 1100 nm to 170 nm. This FEL serves as a photon source for the High Intensity Gamma-ray Source (HIGS), producing polarized, near-monochromatic, and high-flux Compton gamma-ray...
High flux, coherent hard X-rays constitute an efficient tool for applications in high resolution (sub nm) chip metrology which offers notable advantages to the modern semiconductor industry. A candidate source for such photons is represented by a recently proposed compact X-rays free electron laser (XFEL) based on high gradient cryogenic accelerating structures and short period cryogenic...
The Electron Ion Collider (EIC), to be constructed at Brookhaven National Laboratory, will collide polarized high-energy electron beams with hadron beams, achieving luminosities of up to 1e+34 cm^−2 s^−1 in the center-mass energy range of 20-140 GeV. Crab cavities are employed to compensate for the geometric luminosity loss caused by a large crossing angle of 25 mrad in the interaction region....
The Electron Ion Collider (EIC), to be constructed at Brookhaven National Laboratory, will collide polarized high-energy electron beams with hadron beams, achieving luminosities up to 1e+34 cm^−2 s^−1 in the center-mass energy range of 20-140 GeV. The current fractional design tunes for the Hadron Storage Ring (HSR) are (0.228, 0.210) to mitigate the effects of synchro-betatron resonances. In...
The cavity-based x-ray free-electron laser (CBXFEL) R&D project utilizes a low-loss x-ray cavity (65.5 m long) to provide circulating monochromatized x-ray seeding for electrons from the Cu-linac at SLAC. The project aims to demonstrate the two-pass gain in x-ray regenerative amplifier and XFELO modes by 2024. Here, we report on the design, manufacture, and characterization of x-ray optical...
The 2016 Relativistic Heavy Ion Collider (RHIC) Au-Au run took place from January 25 to June 27, 2016. Four so-called vernier scans were performed at 100 GeV per beam, with γ=107.396 at flattop at one of the interaction points, IP6. During this type of procedure, one beam is swept across the other, first horizontally and then vertically, recording the interaction rate as a function of the...
FRIB is in user operation more than one year. Statistics and lessons learned will be presented.
Metamaterials could allow developing superconductive-like materials at ambient temperature, with consequent drastic reduction in energy consumption. They are therefore promising materials for future accelerators of small and big scale. Here, electromagnetic metamaterials to synthesize an equivalent structure that approaches superconductive-like properties, i.e. extremely high electrical...
The 3-GeV RCS (Rapid Cycling Synchrotron) at J-PARC (Japan Proton Accelerator Research Complex) simultaneously delivers high-intensity proton beam to the muon and neutron production targets at the MLF (Material and Life Science Experimental Facility) as well as to the MR (Main Ring). Beam loss mitigation is highly essential not only to keep the machine activation lower for maintaining a stable...
The Los Alamos Neutron Science Center (LANSCE) is one of the oldest operating high-power accelerators in the United States, having recently celebrated its 50th anniversary of operation. LANSCE is comprised of an 800-MeV linac capable of concurrently accelerating both H+ and H- ions, and can presently provide beam to six separate user stations.
The proposed LANSCE Modernization Project (LAMP)...
The main ring (MR) of the Japan proton accelerator research complex (J-PARC) delivers the high-intensity proton beams to the T2K long-baseline neutrino experiment. To observe charge-conjugation and parity-transformation violation in the lepton sector with high accuracy, the upgrade of the MR toward the beam power of 1.3 MW is mandatory. The magnet power supply system of MR was upgraded for...
Ongoing studies at the Spallation Neutron Source (SNS) Beam Test Facility (BTF) seek to understand and model bunch dynamics in a high-power LINAC front-end. The BTF has recently been upgraded with a reconfiguration from a U-shaped line to a Straight line. We report the current state of model benchmarking, with a focus on RMS beam sizes within the FODO line. The beam measurement is obtained...
The nuSTORM experiment aims to create neutrino beams through muon decay in a storage ring, targeting %-level precision in flux determination. With access to two neutrino flavors, it enables precise measurement of nu-A cross sections and exhibits sensitivity to Beyond Standard Model (BSM) physics. With muons in the 1-6 GeV/c momentum range, it covers neutrino energy regimes relevant to...
During the third run of the Large Hadron Collider in 2023, which had the highest intensity bunch population compared to previous runs, increased losses attributed to pressure spikes within a warm vacuum sector triggered a beam dump. Subsequent inspections revealed localised annealing and plasticisation of the tension spring in the sliding contact radio-frequency finger module, alongside traces...
Monochromatization of the beams is presented as a technique to reduce the energy spread and thus improve the CM energy resolution in colliding-beam experiments. Monochromatization consists of generating opposite correlations between a spatial position and the energy deviation in the colliding beams. In beam-optics terms, this can be achieved by generating a nonzero dispersion function of...
FACET-II is the recently completed 10 GeV electron beam facility at SLAC National Accelerator Laboratory. The latest results on the flagship E300 experiment on Plasma Wakefield experiment will be presented.
The Electron Ion Collider (EIC) Hadron Storage Ring (HSR) will reuse most of the existing hardware from the RHIC rings. However, extensive modifications will have to be performed in preparation for the new accelerator parameters and performance required by EIC. The beam vacuum chamber will have to be upgraded and new beam position monitors (BPM) implemented to account for the higher beam...
A Dielectric Disk Accelerator (DDA) is a metallic accelerating structure loaded with dielectric disks to increase its shunt impedance. These structures use short RF pulses of 9 ns to achieve accelerating gradients of more than 100 MV/m. Single cell and multicell clamped structures have been designed and high power tested at the Argonne Wakefield Accelerator. During testing, the single cell...
In 2023, the Pb-Pb run in the Large Hadron Collider (LHC) took place during the last five weeks of operation at a record beam energy of 6.8 Z TeV. It marked the first heavy-ion run of Run 3, following a two-day test that took place in 2022 to verify some key machine and beam upgrades. The 2023 run profited for the first time of higher beam intensities than the previous runs and of machine...
Most current laser-plasma accelerators (LPAs) require driver lasers with relativistic intensities and pulse durations that are significantly shorter than the plasma wavelengths. This severely limits the laser technology that can be used to drive LPAs and with that their wide spread and the currently achievable LPA parameters, such as repetition rate and accelerating gradient. Here, we report a...
In the SuperKEKB/Belle-II experiment, a multitude of elementary particle reactions is initiated through the collision of 4 GeV positrons with 7 GeV electrons, paving the way for the exploration of new physics. The experiment includes plans for the substantial enhancement of luminosity in the future, aiming to achieve an integrated luminosity approximately 100 times the current level. However,...
The viability of next generation, compact, TeV-class electron-positron colliders based on staging of independently-powered plasma-based accelerators relies on the possibility of accelerating high-charge bunches to high energy with high efficiency and high accelerating gradient, while maintaining a small energy spread and emittance. Achieving a small energy spread with high-efficiency requires...
SHINE (Shanghai Hard X-ray FEL Facility) is a high repetition rate X-FEL facility under construction in Shanghai, China. The facility is based on an 8 GeV CW superconducting linac and plans to have 3 undulator lines and 10 experimental stations in phase-I, covering the photon energy range of 0.4 – 25 keV. Mass production of the components and installation of the machine are in course. User...
TAE Technologies (TAE) is a privately funded company pursuing a novel approach to magnetic confinement fusion, which relies on Field-Reversed Configuration (FRC) plasmas stabilized and sustained with high power Neutral Beam Injection (NBI). This advanced FRC-based system simplifies reactor design and could offer a path forward to economical aneutronic fusion.
To validate the science behind...
The Advanced Photon Source Upgrade (APS-U) is a 4th generation 6-GeV synchrotron light source based on a hybrid seven-bend achromat lattice with a record emittance goal of ~40 pm-rad. It is the first storage ring light source that implements full-charge bunch injection in a scheme known as swap-out. APS-U completely replaces the APS storage ring while largely keeping the original injectors and...
Alkali antimonide and telluride photocathodes are widely used in modern photoinjectors and are primary candidates for the most demanding future accelerator applications that require bright and intense electron beams. We report on the progress of the technology maturation and transfer initiative aimed at achieving reproducible automated growth of the alkali antimonide thin films, in order to...
Light drives innovation – the wavelength, the power, the intrinsic qualities. From the mask shop to the packaging fab, from lithography to metrology, each technology node has relied on light invention to enable scaling, process control, reliability, and even ensuring supply chain security. However, the increasing cost and complexity of new light sources to meet industry demands has become...
The vertical beam halo is the main limitation for very low gap operation of in-vacuum undulators at the ESRF EBS. The vertical halo is due to Touschek electrons with large energy deviation crossing some betatron resonances. The crossing of the resonances can transfer horizontal momentum to vertical momentum. The beam halo has been characterized and measured and different low halo optics have...
This report describes the development overview of future science accelerators in Asia, focusing on projects that have emerged, conceptual designs that exist, and plans that may be constructed, commissioned, and operated within next 5 to 10 years. The scope covers accelerators in three major scientific directions: experimental high-energy physics (colliders), applied science (synchrotron...
In the latest years Machine Learning (ML) has seen an unprecedented diffusion in the most different fields in simulations and real life as well. Probably two of the first and most used ML applications in accelerators are the optimization of the final performance of the machines, and the so called virtual diagnostics. In the latest years ML was successfully applied to improve the machine safety...
Particle accelerator projects in Europe are continuously growing and are used in a wide range of domains, ranging from basic science via applied science to applications such as medicine and industry. Traditionally the strongest demands in terms of technologies and performance are coming from particle physics, from which new technologies extend to other applications and finally reach the...
The Compact X-ray Light Source (CXLS) is a compact source of femtosecond pulses of x-rays that is now commissioning in the hard x-ray energy range 4-20 keV. It collides the beams from recently developed X-band distributed-coupling, room-temperature, standing-wave linacs and photoinjectors operating at 1 kHz repetition rates and 9300 MHz RF frequency, and recently developed Yb-based lasers...
Positron source yield is a key factor for reaching the luminosity needed in future lepton colliders. Conventional scheme relies on a few GeV e-beam impacting on a high-density solid target to initiate an e.m. shower and collect the positrons after the target. This scheme is limited by the maximum heat load on the target before its structural failure.
An innovative approach to overcome such...
Osprey DCS is developing the Machine Learning Data Platform (MLDP) supporting data science applications specific to large particle accelerator facilities and other large experimental physics facilities. It represents a “data-science ready” host platform providing integrated support for advanced data science applications used for diagnosis, modeling, control, and optimization of these...
An effective high-power positron converter for electron linear accelerators is not currently available from industry. A commercial source would allow research institutes to have ready access to high-brightness positrons for a wealth of material science, nuclear, particle, and accelerator physics projects. Xelera Research LLC has designed, built, and tested a prototype free-surface liquid-metal...
The Electron Ion Collider calls for polarized proton and helion beams on polarized electron beam collisions. To preserve polarization of polarized hadron beams, six full helical snakes will be installed. As there are currently 4 snakes in RHIC, the remaining two snakes will be made from existing rotator magnet coils. The rotator magnets are made from both right handed and left handed...
The performance of a photoinjector relies on the brightness preservation. For acceleration structures used for emittance compensation, it will lead to a smaller additional emittance growth with fewer nonlinearities. To compensate for the possible asymmetry on both sides of the installation, an S-band acceleration structure with a novel coupler was designed. The beam test results show a...
A new two-stage collimation unit (2SC) for Fermilab Booster will be installed during 2024 summer shutdown. It is a supplementary collimator for existing single stage Booster collimators. Unique operational principles of this new 2SC adapted to Booster conditions are described. Results of beam dynamics simulations on collimation efficiency of the new 2SC are presented. Evaluation of collimator...
The upcoming High-Luminosity Large Hadron Collider (HL-LHC) program requires a beam performance in the CERN Proton Synchrotron (PS) that is at the limits of the current RF systems. Following the discontinuation of the RF tube production of the driver amplifiers a new solid-state design has been developed using radiation-hard amplifier technology. In view that the current system architecture...
The Electron-Ion Collider (EIC) is a cutting-edge accelerator designed to collide highly polarized electrons and ions. For enhanced luminosity, the ion beam is cooled via an electron beam sourced from an energy recovery linac (ERL). The current ERL design accommodates one RF cavity per cryomodule, presenting both beam transport and cost-related challenges. This study investigates the...
Two of the major scientific drivers of particle physics and cosmology are the faith of antimatter after the Big Bang and the origin of Dark Matter. The answers to these questions can be addressed by investigating permanent and oscillating Electric Dipole Moments (EDM) of fundamental particles. The experiments can be performed with polarized beams in a dedicated storage ring.
Important...
The 2023 Particle Physics Project Prioritization Panel recommends an updated approach for accelerator R&D activities in the US research program. Key recommendations for the DOE-HEP General Accelerator R&D Program, a new targeted Collider R&D program, and the potential for increased engagement with the NSF are described.
Despite a shorter-than-scheduled physics run due to a hardware problem, the AD/ELENA antiproton complex delivered record beam intensities to the experiments during the 2023 run. This paper reviews the performance of both the CERN Antiproton Decelerator (AD) and the Extra Low ENergy Antiproton (ELENA) decelerator and their associated transfer lines. It presents the main improvements that...
The International Linear Collider (ILC) requires crabbing system to compensate 14 mrad crossing angle. The crabbing system at 1.3 GHz needs to provide 1.845 MV crabbing voltage for 250 GeV case and 7.4 MV for 1 TeV case and needs to be fitted within 3.8 m allocated space. In this paper, a Wide-Open-Waveguide (WOW) type cavity is proposed as one of the candidates due to its simple structure and...
A very high electron peak current is needed in many applications of modern electron accelerators. To achieve this high current, a large energy chirp must be imposed on the bunch so that the electrons will compress when they pass through a chicane. In existing linear accelerators (LINACs), this energy chirp is imposed by accelerating the beam off-crest from the peak fields of the RF cavities,...
The PIP-II proton accelerator will provide the intensity sufficient to power a new generation of high energy facilities at Fermilab. Extension of that linac to higher energy with following acceleration and bunching rings could provide the intensity needed to feed a muon production target for a high-energy μ+-μ- collider. Scenarios using a rapid-cycling synchrotron or an ~8 GeV Linac are...
Efficient calculation of multi-dimensional derivatives of various performance metrics of RF sources with respect to different design parameters is a critical element of their optimization and sensitivity analysis. The direct approach is to change slightly the value of a design parameter of interest and compute the resulting change in the metric of interest; an example is a calculation of how a...
A new charge selector is currently under development at FRIB to intercept unwanted charge states of higher-power 17 - 20 MeV/u stripped heavy ion beams. The charge selector is located in the first bending segment of the FRIB linac, where high dispersion separates charge states to allow for their selection. The design concept is based on rotating graphite cylinders that act as an intermediate...
Ultrafast high-brightness X-ray pulses have proven invaluable for a broad range of research. Such pulses are typically generated via synchrotron emission from relativistic electron bunches. Recently, compact X-ray sources based on laser-wakefield accelerated (LWFA) electron beams have been demonstrated, where the radiation is generated by transverse betatron oscillations of electrons within...
An Yb:YAG laser has been used to generate both the electron emission from a photocathode and act as the interaction laser on a 100 MeV inverse Compton scattering experiment. The laser generates 25 mJ pulses at 1030 nm, 1.5 ps long, up to 120 Hz. 10 % of the energy is sent into a Fourth Harmonic Generation (FHG) module where frequency doubling happens twice. Up to 200 µJ of adjustable...
The design and study of the Circular Electron Positron Collider (CEPC) present a significant challenge, requiring the proper modeling of various physical phenomena such as the crab-waist collision scheme with a large Piwinski angle, strong nonlinear effects, energy sawtooth, beam-beam interactions, and machine impedances. In response to this challenge, the APES software project was proposed in...
In anticipation of the Eupraxia@SPARC_LAB project at the INFN Frascati National Laboratories, an intensive testing and validation activity for the X-band RF system has commenced at the TEX test facility. The Eupraxia@SPARC_LAB project entails the development of a Free-Electron Laser (FEL) radiation source with a 1 GeV Linac based on plasma acceleration and an X-band radiofrequency (RF)...
ALBA is working on the upgrade project that shall transform the actual storage ring, in operation since 2012, into a 4th generation light source, in which the soft X-rays part of the spectrum shall be diffraction limited. The project was launched in 2021 with an R&D budget to build prototypes of the more critical components. The storage ring upgrade is based on a MBA lattice which has to...
The ALS-U project is an upgrade to the Advanced Light Source (ALS) at the Lawrence Berkeley National Laboratory that aims to deliver diffraction-limited x-ray beams with an increased beam brightness of two orders of magnitude for soft x-rays compared to the current ALS facility. A nine-bend achromat lattice Storage Ring (SR) and a three-bend achromat Accumulator Ring (AR) will be installed in...
We present the optics design of the solenoid compensation scheme at the FCC-ee. The 2T solenoids from the experiments induce coupling on the beams, generating an increase on vertical emittance. This compensation scheme minimizes emittance growth, with a final value of approximately 5% of the nominal. A screening solenoid is placed around the Final Focus Quadrupoles to protect them from the...
Steady-state microbunching (SSMB) represents an innovative scheme for generating high-power coherent radiation. This approach is expected to generate kilowatt-scale extreme ultraviolet (EUV) radiation for lithography in the semiconductor industry. During the second phase of the SSMB proof-of-principle experiment (SSMB PoP II), the creation of quasi-steady-state microbunches requires specific...
An input port for the magnetron uses the helix of the filament as an antenna into the resonant structure of the magnetron. Analytical results indicate the coupling variables in pitch and radius of the filament. High voltage standoff includes a combination of DC blocks and capacitive coupling techniques in either waveguide or coax. The importance of this novel innovation in magnetron...
The Los Alamos Neutron Science Center (LANSCE) is one of the oldest operating high-average-power accelerators in the United States, having recently celebrated its 50th anniversary of operation. LANSCE is comprised of an 800-MeV linac capable of concurrently accelerating both H+ and H- ions, and can presently provide beam to six separate user stations. The LANSCE accelerator operates with much...
The Los Alamos Neutron Science Center (LANSCE) is one of the oldest operating high-average-power accelerators in the United States, having recently celebrated its 50th anniversary of operation. LANSCE is comprised of an 800-MeV linac capable of concurrently accelerating both H+ and H- ions, and can presently provide beam to six separate user stations.
The Proton Storage Ring (PSR) at LANSCE...
The Electron Ion Collider (EIC) Hadron Storage RIng (HSR) requires the crossing of transition for all species except for protons. The current scheme for the Relativistic Heavy Ion Collider (RHIC) utilizes the gamma transition quadrupoles will be adopted for the scheme of the HSR. With rebuilt straight sections, the jump quadrupoles responsible for tune compensation will need to be placed at...
This study examines Laser Engineered Surface Structures (LESS) in the context of their potential application within particle accelerators. These structures are investigated due to their efficient reduction of secondary electron yield to counteract the formation of electron clouds, a phenomenon detrimental to accelerator performance. A critical aspect of their evaluation involves understanding...
The n_TOF is one of the few neutron spallation facilities in the world capable of delivering neutron spectra. These spectra are used for precise neutron-induced cross-section measurements using the time of flight technique. The facility has made significant contributions to a wide range of scientific fields including astrophysics, nuclear technologies and medical applications since the...
In accelerator physics, channeling is a well-established phenomenon. By carefully selecting crystal orientation, particle’s trajectories can be controlled and guided along desired paths. Bent crystals have been used at worldwide particle accelerators as optical elements to steer charged particle beams, with an elective application related to the collimation of the lead ion beam circulating in...
In this paper, we delve into the application and comparative analysis of the Accelerator Physics Emulation System Cavity-Beam Interaction (APES_CBI) module within the BEPC-II (Beijing Electron-Positron Collider) experiments. We developed the APES_CBI module as an advanced time-domain solver, specifically designed to analyze RLC circuits driven by beam and generator currents and to simulate the...
In this study, we present a lattice design for the dif-fraction limited storage ring (DLSR), achieving an ultra-low natural emittance of 25.6 pm·rad (N-IBS). To address the significant intra-beam scattering (IBS) effect resulting from the ultra-low emittance and long damping times, Horizontal Field Damping Wigglers (HFDWs) have been adopted. These components de-crease damping times and beam...
In our pursuit to tailor a precise electron bunch with a photoinjector, fine-tuning laser parameters, especially those influencing the photocathode pulse, is pivotal. Our ongoing research integrates machine learning, training neural networks with experimental data from ATF. The first approach involves generating a downstream photocurrent image to replicate the emission profile, serving as a...
After a long shutdown, the Advanced Photon Source (APS) booster synchrotron was recently re-commissioned for the APS Upgrade (APS-U) project. The APS-U requirements for the booster are more demanding than the old APS: much higher bunch charge, reduced beam emittance, and improved charge stability of better than 5% shot to shot. The booster accelerates electron bunches of 1-12 nC from 425 MeV...
The ATF2-3 beamline is the only facility in the world for testing the Final Focus Beamline of linear colliders and is essential for the ILC and the CLIC projects. A vertical electron beam size of 41 nm (within 10% of the target), a closed-loop intra-bunch feedback of latency 133 ns, and direct stabilization of the beam position at the Interaction Point to 41 nm (limited by IP BPM resolution)...
Super-NaNu is a proposed neutrino experiment as part of the SHADOWS proposal for the high intensity facility ECN3 in CERN's North Area. It aims to detect neutrino interactions downstream of a beam-dump that is penetrated with a 400 GeV high intensity proton beam from the SPS. The experiment would run in parallel to the HIKE and SHADOWS experiments, taking data with an emulsion detector....
High Power Targetry (HPT) R&D is critical in the context of increasing beam intensity and energy for next generation accelerators. Many target concepts and novel materials are being developed and tested for their ability to withstand extreme beam environments; the HPT R&D Group at Fermilab is developing an electrospun nanofiber material for this purpose.
The performance of these nanofiber...
The Canadian Light Source (CLS) storage ring RF frequency varies on timescales of seconds to days. Over approximately 20 years it has drifted from its design value. We outline and discuss our efforts to identify, disentangle and mitigate the potential sources of variations in the RF frequency on various timescales. These sources include the building temperature regulation, the orbit correction...
This work examines the multi-pass steering of six electron beams in an FFA arc ranging from approximately 10.5 GeV to 22 GeV. Shown here is an algorithm based on singular value decomposition (SVD) to successfully steer all six beams through the arc given precise knowledge of all beam positions at each of one hundred and one diagnostic locations with one hundred individual corrector magnets:...
The P42 beamline transports 400 GeV protons from the CERN SPS between the T4 and T10 targets. A secondary particle beam is produced at the T10 target and transported along the K12 beamline to the experimental cavern ECN3, presently housing the NA62 experiment. In the context of the Physics Beyond Colliders (PBC) study, an increase of the beam intensity in P42 has been considered to provide...
The proton storage ring (PSR) upgrade for the LANSCE Modernization Project aims to minimize the yearly maintenance outage by minimizing beam loss. Several improvements could potentially impact the beam dynamics in the PSR, including a larger coated beam pipe and new buncher, injection, and extraction systems. The larger diameter, from 4” to 6”, will directly impact the beam dynamics due to an...
DESY is planning to upgrade PETRA III to a 4th generation light source. The magnetic lattice components are pre-installed and aligned on long girders before being installed in the tunnel. These long girders and the misalignment of the magnets pose a challenge for the PETRA IV lattice, including the storage of the beam in the ring. Commissioning simulations have been performed which showed that...
In 2023, the LHC started its Run 3 operation with 208Pb82+ beams at 6.8 ZTeV, with a substantially higher number of bunches compared to past runs. Several new hardware systems were used operationally for the first time with high-intensity beams, including bent crystal collimators in the betatron cleaning insertion. Crystal-assisted collimation reduces the leakage of secondary ion fragments to...
The BESSY III project evolves from a pre-CDR phase into the CDR phase. And for lattice design, it means, that one of the different Higher-Order-Achromat MBA lattice candidates has to be chosen as the baseline lattice for the iterations with the construction department. Therefore it is essential that the design of the main and most important components, the bending magnets, will be defined as...
Slow resonant extraction plays a crucial role in delivering a high-quality continuous beam to experiments. Simulating extraction and transport of charged particle beams require a process of careful modeling and experimentation. There are various particle tracking simulation tools available to use. Each has its merits and deficiencies. In this work we have used long-term tracking based on the...
LIV.INNO is a new initiative which will train around 40 PhD students over three cohorts. It fosters innovation in data-intensive science, serves as a dynamic platform for collaboration between leading research organizations and the next generation of scientists. Within this context, several projects focus on research that intersects between data science and particle accelerator...
A novel double-crystal experiment is being considered for installation in CERN’s Large Hadron Collider (LHC) to measure precession properties of short-lived baryons such as the Λc+. The experiment utilises a first bent silicon crystal of 50 µrad to deflect halo particles away from the circulating proton beam. Further downstream, a second crystal is installed, which produces a significantly...
The Southern Advanced Photon Source (SAPS) is a 3.5 GeV, kilometer-scale, ultra-low emittance storage ring to be built next to the CSNS (China Spallation Neutron Source) in Guangdong Dongguan, China. A lattice design of storage ring was proposed, consisting of 32 modified hybrid 7BAs, and having a natural emittance of 26.3 pm·rad and a circumference of ~810 m. In this paper, a candidate...
400 GeV protons extracted from the CERN SPS are transported to the T4 target via the TT20 transfer line. The P42 beamline then transports the protons that did not interact in the T4 target to the T10 target. During operation in 2021 and 2022, higher than expected beam losses were measured, in addition to an increased beam spot size that had previously been observed. It was suspected that the...
A large challenge with Plasma Wakefield Acceleration lies in creating a plasma with a profile and length that properly match the electron beam. Using a laser-ionized plasma source provides control in creating an appropriate plasma density ramp. Additionally, using a laser-ionized plasma allows for an accelerator to run at a higher repetition rate. At the Facility for Advanced Accelerator...
The secondary beam production target at future positron sources at the Continuous Electron Beam Accelerator Facility (CEBAF), the International Linear Collider (ILC) or the Future Circular Collider (FCC), features unprecedented mechanical and thermal stresses which may compromise sustainable and reliable operation. Candidate materials are required to possess high melting temperature together...
Bunches excited by a transverse kick out of the closed orbit develop betatron oscillations, whose dynamics is affected by the chromaticity used in the accelerator or storage ring. Specifically, decoherence and recoherence effects caused by chromaticity can be modified by introducing Landau damping in the synchrotron phase space, when using a harmonic cavity to stretch the bunch length in order...
We calculate the coherent radiation of a modulated beam in a short resonantly tuned undulator taking into account the finite transverse size and the angular spread of the beam. The result allows to optimize the radiation by controlling the Twiss parameters in the undulator.
Horizontal and vertical collimators will be installed in the Diamond-II storage ring to protect the ring components against undesired losses and radiation showers. Different loss mechanisms have been studied, including lifetime effects, RF trips, injection losses and kicker misfire. In this paper, we present the latest collimator layout and collimation efficiency. In addition, the risk of...
For the China Spallation Neutron Source (CSNS), the rapid cycling synchrotron (RCS) accumulates and accel-erates the injection beam to the design energy of 1.6 GeV and then extracts the high energy beam to the target. In this paper, the commissioning of 160 kW beam power for the CSNS RCS have been comprehensively studied, in-cluding: increase of the pulse width for the injection beam to...
The CW electron accelerator ELBE is in operation for more than two decades. The timing system has been patched several times in order to meet changing requirements. In 2019 the development of a new timing system based on Micro Research Finland Hardware has been started which is designed to unify the heterogeneous structure and to replace obsolete components. In spring 2024 the system has been...
Beam based alignment (BBA) plays an important role in the commissioning of the fourth generation light source but it takes a lot of time with several hundreds of BPMs. To speed up BBA, a method using AC excitation, called fast BBA, has been proposed and is tested in several 3rd generation light sources. We have recently also proposed and tested a new BBA based on the neural network machine...
Modern synchrotron light sources are competing intensively to increase X-ray brightness and, eventually, approach the diffraction limit, which sets the final goal of lattice emittance. Recently, we propose a new optics solution aimed at reaching low emittance, using a lattice element “Complex Bend”. The Complex Bend is a sequence of dipole poles interleaved with strong alternate focusing so as...
Conceptual design work is under way for a fourth generation light source in Australia.This new light source is being designed as a completely new facility, intended to come into operation around 2037 as the current Third generation Australian Synchrotron reaches its end of life. Previous design work was done to consider a 600 m ring, but on review the decision was made to reduce the...
For the future multi-TeV muon collider, ionization cooling is a critical step to achieve the required beam emittance for a proton-driven muon beam. Ionization cooling of intense muon beams requires the operation of high-gradient, normal-conducting RF structures in the presence of strong magnetic fields. The MAP modular cavity study at Fermilab has demonstrated the RF breakdown threshold at 13...
The operation of the COler SYnchrotron COSY and its further development ended in October 2023. We briefly review the operation of the accelerator facility and continuous development of its sub-systems. Additionally, this work is put in context of the transformation process that COSY operation and the Institute of Nuclear Physics (IKP) of the Research Center Jülich went through starting 2015....
Proton polarization is preserved in the AGS by using helical dipoles partial snakes to avoid depolarizing vertical resonances. These same helical dipoles also drive numerous (82) weak horizontal resonances that result in polarization loss. These horizontal resonances occur at the same energy (and therefore frequency) as depolarizing resonances driven by linear betatron coupling. A new scheme...
This paper details the implementation and benchmarking of crystal collimation within MERLIN++ accelerator physics library and demonstrates its application in simulating crystal collimation process for the High Luminosity upgrade of LHC at CERN. Crystal collimation is one of the key technologies suggested to enhance the current collimation system according to the requirements of HL-LHC upgrade...
The attainable acceleration gradient in normal conducting RF accelerating structure is limited by RF breakdown, a major challenge in high gradient operation. Some of the recent experiments at the Argonne Wakefield Accelerator (AWA) facility suggest the possibility of breakdown mitigation by using short RF pulses (on the order of a few nanoseconds) to drive the accelerating structures. To...
In accelerator labs like GSI/FAIR, automating complex systems is key for maximizing physics experiment time. This study explores the application of a data-driven model predictive control (MPC) to refine the multi-turn injection (MTI) process into the SIS18 synchrotron, departing from conventional numerical optimization methods. MPC is distinguished by its reduced number of optimization steps...
The ALS-U project to upgrade the Advanced Light Source to a multi bend achromat lattice received CD-3 approval in 2022 marking the start of the construction phase for the Storage Ring. Construction of the accumulator under a prior CD-3A authorization is already well advanced. ALS-U promises to deliver diffraction limited performance in the soft x-ray range by lowering the horizontal emittance...
Recent efforts at SLAC aim at developing high-power accelerators powered by compact, high-efficiency RF sources such as klystrons and Inductive output tubes (IOT). Stellant Systems (formerly L3Harris Electron Devices) has long pioneered the IOT design and recently leveraged its power toward various accelerator applications. In this talk, we show the progress of developing a 1.3 GHz HEIOT in...
Jinhua Light Source, which is a industrial light source, will be built in Jinghua City, Zhejiang Province, China. Its energy is 2.6 GeV and beam current is 500 mA. 4 sets of normal-conducting RF systems are likely to be chosen. A kind of 500 MHz HOM-damped normal conducting RF cavity has been designed for the Jinhua Light Source. The KEK-PF main cavity type was selected and three rectangular...
The upgrade of PETRA III to PETRA IV at DESY is currently in its design phase. To achieve the desired beam parameters a 3rd harmonic cavity is necessary for the accelerating system. An investigation of three types of cavity structures thus is conducted to find the most cost effective and environmentally sustainable option.
A high focus in this investigation is placed on the damping of higher...
Higher-order mode (HOM) damping is essential for building large-scale facility linear accelerators, such as a linear collider, because of the need to reduce the wakefield strength inside the accelerating structure. We designed a C-band accelerator cavity with distributed coupling and thin HOM-damping waveguides oriented in the radial direction. It was proposed that nickel-chrome (NiCr) coating...
As compared to conventional travelling-wave (TW) structures, parallel-coupled accelerating structures eliminate the requirement for the coupling between cells, providing greater flexibility in optimizing the shape of cells. Each cell is independently fed by a periodic feeding network for this structure. In this case, it has a significantly short filling time which allows for ultrashort pulse...
The Advanced Photon Source Upgrade (APS-U) will deliver a new storage ring based on a Multi-Bend Achromat (MBA) lattice featuring swap-out on-axis injection, enabling the use of small diameter insertion device vacuum chambers. To leverage this advantage, we designed an X-undulator similar to the APPLE-X undulator but with a fixed gap and additional simpler magnet arrays for force compensation....
The EIC will collide high energy and highly polarized hadron and electron beams with luminosities up to 1e+34 /cm^2/s. Bremsstrahlung photons from the Bethe-Heitler process at the interaction point (IP) need to be counted to determine the delivered luminosities. The pair spectrometer luminosity detector utilizes photon conversions (e+ and e- pairs) in the far-backward region. A sweeper dipole...
To reduce the electric power consumption and advance the magnetic stability, a prototype of BTS dipole magnet in TPS transfer line between booster and storage ring came into sight. An 1 m long, high current dipole will be replaced by a permanent magnet with Sm2Co17. The new permanent dipole magnet will decrease total volume compared with original electric one, and the homogeneity of integral...
In the paper, we simulate and calculate a side-coupled proton accelerating structure with high shunt impedance and Q factor by optimizing the key parameters of the nose cone. The accelerating structure consists of accelerating cell and coupling cell and operates on bi-period mode.
A dual energy electron storage ring cooler was proposed to maintain a good hadron beam quality against intra-beam scattering and all heating sources in a collider. This configuration has two energy loops. Electron beam in the low energy loop extracts heat away from the hadron beam through Coulomb interaction, while electron beam in the high energy loop loses heat through its intrinsic...
A quadruple wiggler consisting of a row of alternating polarity quadrupoles is used in a collinear wakefield accelerator under development at Argonne National Laboratory. We designed such a wiggler and fabricated a prototype consisting of four quadrupoles. The permanent magnet-excited quadrupole has a bore diameter of 3 mm, a length of 25 mm, and a peak magnetic field gradient of 0.94 T/mm....
In the framework of the MYRRHA programme, a large-scale Accelerator Driven System (ADS) being implemented by SCK CEN in Belgium, a fast pulsed magnet system is being designed and specified at CERN. A complete design study has been performed to develop the specifications and drawings for a kicker magnet, as well as the associated pulse generator to deflect the 100 MeV proton beam. This paper...
Ultrafast Microscopy using MeV beam has made significant progress in the past 5 years. However, in order to push to atomic level resolution, other than the requirements of beam source, there are also high demands in high strength focusing elements. In comparison of commercial 100s KeV level electron microscopes, an MeV imaging beamline requires Tesla level lenses, preferably round solenoid...
For several years, significant effort has been spent at GSI to improve the time structure of the spill during slow extraction in SIS18. This led to the requirement to extend the possibilities to experimentally improve the micro-spill structure by partially or fully capturing the beam with an RF of more than 40 MHz. Therefore, a so-called spill-structure manipulation cavity was designed,...
The electron cooler of the Antiproton Decelerator (AD) at CERN was initially developed for the Initial Cooling Experiment in 1979. It was subsequently adapted for use at LEAR and is currently employed in the AD. However, certain components of the cooler are now more than 40 years old and lack spare parts. To ensure the reliable operation of the AD, a new electron cooler is under...
The ALBA synchrotron light source is in the process of a significant upgrade, aiming to become a fourth-generation facility by reducing its emittance by at least 20 times. The initial phase of this project involves a comprehensive prototyping program designed to validate various critical technologies, such as magnets, vacuum systems, girders, etc., essential for facilitating the impending...
The power coupler is one of the most important components for superconducting cavities. Different from the normal conducting cavity, the superconducting cavity has to keep an ultra-high cleanliness environment for operation. As the vacuum barrier, power couplers are welded by many different materials and maybe the gas source since they are installed to the cavities after vertical test,...
X-ray Free Electron Lasers (XFELs) are transformative across multiple disciplines, offering high power and tunable wavelengths. Facilities like FLASH, LCLS, and SwissFEL, including China’s SXFEL and SHINE, provide ultra-bright femtosecond X-ray pulses. Their operation hinges on the precise synchronization of RF and laser sources, typically using femtosecond lasers as the master clock...
The THz spectrum reveals distinctive vibrational and rotational modes, and when charged particle beams produce THz radiation, it becomes a promising source for generating narrowband, high-energy radiation. Particularly in dielectric wakefield accelerators, where a dielectric-lined channel is traversed by a relativistic electron beam, coherent Cerenkov radiation (CCR) is generated. The...
The 3.0 GeV ALBA Synchrotron Light Source, in operation with users since 2012, is looking forward an upgrade aimed at enhancing the brightness and coherence fraction of the delivered X-ray beam. The Storage Ring (SR) will be completely renewed but we plan on keeping the same orbit length and the position of the ID source points. The energy of the electrons will be preserved and the same...
Future colliders will require injector linacs to accelerate large electron bunches over a wide range of energies. For example the Electron Ion Collider requires a pre-injector linac from 4 MeV up to 400 MeV over 35 m*. Currently this linac is being designed with 3 m long traveling wave structures, which provide a gradient of 16 MV/m. We propose the use of a 1 m distributed coupling design as a...
IFMIF-DONES is an ESFRI facility based on a 5 MW deuteron accelerator currently under construction in Granada (Spain) as part of the European roadmap to fusion electricity. Its main goal is to characterize and qualify materials under a neutron field with an induced damage like the one faced in a fusion reactor, developing a material database for the future fusion nuclear reactors. Moreover, a...
The Ring Electron Cooler (REC) is currently under design for use in the Electron Ion Collider (EIC) for hadron cooling. In this device the hadrons are cooled by the electrons and the electrons are cooled through radiation damping, which is enhanced by a number of 4 meter-long wigglers with 2.4 T field. When optimizing the beam envelope, intra beam scattering and Touschek scattering are also...
The Rapid Cycling Synchrotron (RCS) of the Electron Ion Collider (EIC) will be used to accelerate polarized electrons from 400 MeV to a top energy of 5, 10, or 18 GeV before injecting into the Electron Storage Ring. At 1 GeV, the RCS will perform a merge of two bunches into one, adding longitudinal dynamics that effects the dynamic aperture, depending on the merge parameters. In this paper,...
The computation of residual gas density profiles in particle accelerators is an essential task to optimize beam pipes and vacuum system design. In a hadron collider such as the LHC, the beam induces dynamic effects due to ion, electron and photon-stimulated gas desorption. The well-known VASCO was already used to estimate pressure profiles in steady state conditions. Nevertheless, some...
Echo-enabled harmonic generation (EEHG) has been proposed as a seeding method for free-electron lasers but can also be employed to generate ultrashort radiation pulses at electron storage rings. With a twofold laser-electron interaction in two undulators, each followed by a magnetic chicane, an electron density pattern with a high harmonic content is produced, which gives rise to coherent...
In 2023, an RF technique known as empty-bucket channelling was implemented operationally at the CERN Super Proton Synchrotron (SPS) to improve the quality of the spill provided to the North Area experiments. Empty-bucket channelling suppresses particle-flux variations during resonant slow extraction by accelerating particles between empty RF buckets and rapidly displacing particles into the...
Next-generation accelerator concepts, which hinge on the precise shaping of beam distributions, demand precise diagnostic methods capable of reconstructing beam distributions with 6-D phase spaces. However, the characterization of 6-D beam distributions using conventional techniques necessitates hundreds of measurements, using hours of valuable beam time. Novel diagnostic techniques are needed...
Quadrupole magnets are used extensively in particle accelerators, synchrotrons, and storage rings around the world. High field quality specifications are required for the quadrupole magnets at these facilities. Precise positioning of pole tips is needed to obtain high-quality fields in a quadrupole magnet. Typically, solid quadrupole magnet cores are machined with very high precision to obtain...
The understanding of the dynamic pressure during accelerator operation is fundamental to provide solutions to mitigate pressure rises induced by multiple-effects occurring in the vacuum chambers and leading to beam instabilities. These effects induced by pressure increase have to be well understood to reach high performances for future machines as HL-LHC or FCC-ee. To get a better...
The ESRF-EBS storage ring is operated with constant vertical emittance at 10 pm. The emittance blow-up is obtained with a magnetic shaker exciting the beam with a noise in a range of frequencies including the betatron tunes. The amplitude of the shaker is tuned by a feedback depending on the measured emittance. The coherent oscillations given to the beam by the shaker at each turn become...
CERN Proton Synchrotron (PS) is featured with 100 C-shaped combined-function Main Units (MUs) magnets with a complicated pole shape. The operation and the modelling of the PS-MUs has been historically carried out with empirical beam-based studies. However, it would be interesting to understand whether, starting from a proper magnetic model and using the predicted harmonics as input to optics...
The Future Circular Collider (FCC) study foresees the construction of a 90.7 km underground ring where, as a first stage, a high-luminosity electron-positron collider (FCC-ee) is envisaged, operating at beam energies from 45.6 GeV (Z pole) to 182.5 GeV (ttbar). In the FCC-ee experimental interaction regions, various physical processes give rise to particle showers that can be detrimental to...
The successful injection of proton beams into the Large Hadron Collider (LHC) depends on an efficient scraping mechanism in the Super Proton Synchrotron (SPS). The beams accelerated in the SPS contain a significant non-Gaussian tail population. If not removed, this transverse tail population can cause high losses in the transfer lines and in the LHC injection elements. Subsequently, the Beam...
In the framework of consolidation of the North Experimental Area at CERN, the 4-block secondary beamline collimators have been assessed with engineering studies and optimized for present beamline operation and future performance with higher beam intensities. Insights gained from experience and through an analysis of fault registration during operation, lead to improvements in the collimator...
Compact cyclotrons, with their ability to deliver high-intensity beams, hold immense potential for advancements in radioisotope production, cancer therapy, and materials research. However, achieving this potential has been limited by inherent challenges and technological constraints. This work presents a comprehensive approach to boosting beam current in compact cyclotrons, paving the way for...
This paper proposes a concept for a e+ source based on high energy e- beams incident on conical converter targets, in pursuit of its implementation in future lepton colliders such as FCC-ee. We developed 2 conical target solutions optimized for a state-of-the-art capture system based on an high temperature superconducting solenoid, allowing for a full immersion of the target in a 12.7 T peak...
In this groundbreaking study, an advanced particle-in-cell (PIC) simulation code,QuickPIC, is used to explore beam physics within Plasma Wakefield Accelerators (PWFA). The primary aim is to comprehensively analyze beam distributions, particularly those exhibiting perturbations with significant instabilities. To connect simulated beam distributions to physical observables, the study uses...
SSRF-U, a 3.0 GeV diffraction limited storage ring lattice with emittance of 53.2 pm∙rad, is an alternative to SSRF for future upgrades. A large number of high-field intensity and multi-function magnets are used in this compact lattice, which greatly increases the error sensitivity to the beam. To quickly complete beam commissioning and achieve stable operation in the future, error analysis...
The strong hadron cooling system (SHC) for the electron-ion collider (EIC) consists of the modulator, the microbunching amplifier and the kicker section. In the modulator and the kicker section, the electrons are co-moving with the protons. If the relative velocity of an electron with respect to a proton is small enough, it can be captured by the proton and the resulting neutral particle, i.e....
In this work we explore the estimation and control of a particle accelerator simulation of the 800 MeV linac at Los Alamos National Lab. We use a convolution neural network model with a low dimensional latent space to predict the phase space projections of the beam and beam loss, which are mapped from accelerator settings. In deploying the model, we assume phase space predictions cannot be...
Within the field of Particle Accelerators engineering, the design of cooling channels for its components has heavily relied on experimental correlations to compute convective heat transfer coefficients. These coefficients are believed to have a conservative factor which end up in oversized designs. The following study assesses this conservative factor for fully developed flows, in the laminar,...
Field emission (FE) and vacuum arcs limit the maximum achievable accelerating field of both normal and superconducting cavities. The performance of accelerating cavities can be improved after a long conditioning process. Understanding this process and the formation of vacuum arcs is important for all technologies where vacuum arcs cause device failure. The understanding could be more complete...
Particle accelerators use high field quality magnets to steer and focus beams. Normal conducting magnets commonly use soft iron for the yoke, which is subject to hysteresis effects. It is common practice to use an initialization procedure to accomplish a defined state of the magnet for which its hysteresis behavior must be known. In this article, a variation of the scalar Jiles-Atherton model...
In the final cooling stages for a muon collider, the transverse emittances are reduced while the longitudinal emittance is allowed to increase. In previous studies, Final 4-D cooling used absorbers within very high field solenoids to cool low-momentum muons. Simulations of the systems did not reach the desired cooling design goals. In this study, we develop and optimize a different conceptual...
2023 was the last year of operation for the Cooler Synchrotron (COSY) in Jülich, Germany. To prepare for the extraction of polarized protons at a momentum of 1950 MeV/c to an external target, full advantage of the most recent developments of the COSY control system was taken along with the established hardware of COSY.
Challenges in beam development included the operation close to transition...
Fourth-generation synchrotron radiation sources, which are currently being planned in several accelerator laboratories, require fast orbit feedback systems to correct distortions in the particle orbit in order to meet stringent stability requirements. Such feedback systems feature corrector magnets powered at frequencies up to the kilohertz range, giving rise to strong eddy currents. To...
APS Upgrade is a 6 GeV fourth-generation light source that has been recently assembled at Argonne National Laboratory. APS-U storage ring utilizes hybrid seven-bend achromat with reverse bends and promises a design natural emittance of 42 pm·rad. Due to very strong focusing and highly nonlinear lattice, the first-turn trajectory correction and establishing first stored beam rely heavily on...
The FNAL Booster is a fast cycling 15 Hz resonant circuit synchrotron accelerating proton beam from 400 MeV to 8 GeV. The linac pulse injected into the Booster is ~32 μsec long and fills the ring by multi-turn charge-exchange injection. As part of the PIP-II project, the Booster injection energy and repetition rate will be increased to 800 MeV and 20 Hz respectively. Due to much reduced...
A Force-Neutral Adjustable Phase Undulator (FNAPU) has been constructed at the Advanced Photon Source. The FNAPU is a 2.4-meter-long planar hybrid permanent magnet undulator with a 27-mm period length and a fixed gap of 8.5 mm. It consists of two magnetic assemblies with matching periods: one featuring an undulator magnetic structure and the other a simpler magnet structure to compensate the...
“Three-dimensional spiral beam injection scheme” [1] is a key to realize J-PARC muon g-2/EDM experiment exploring the beyond standard model of elementary physics. Muon is stored in a compact orbit of 0.33 m radius in the super conducting solenoid storage magnet. Appropriate X-Y coupled beam phase space, which strongly coupled radial and solenoid axes, is crucial to inject the beam passing...
To provide confidence in the future commissioning of the Diamond-II storage ring, realistic specifications for the error tolerances have been established. Based on these values, commissioning simulations have been conducted starting from on-axis injection through to stored beam and finally the alleviation of beta-beating caused by insertion devices. The goal of these studies is to develop a...
The China Spallation Neutron Source (CSNS) project is now operating stable at the CSNS campus and the upgrade work (CSNS-Ⅱ) has already started in 2023, meanwhile, the preliminary research work on the south advance photon source (SAPS) project is in progress. More than six types of accelerator cavities: radio frequency quadrupole (RFQ), drift tube linac (DTL), double spoke superconducting...
As part of the Diamond-II upgrade project*, the Diamond storage ring will be replaced with a new modified hybrid 6 bend achromat (M-H6BA) lattice, in which each existing arc sections will be split in two to provide additional mid-straights and thereby increase the ring capacity. The majority of insertion devices currently in operation will be either retained or upgraded, and the new...
I plan to discuss potential offered by Energy-Recovery Linacs (ERLs) and particle recycling for boosting luminosity in high-energy electron-positions and lepton-hadron colliders. ERL-based colliders have promise not only of significantly higher luminosity, but also of higher energy efficiency measured in units of luminosity divided by the consumed AC power. Addition of recycling collided...
Los Alamos Neutron Science Center (LANSCE) is designing a Proton Storage Ring (PSR) refurbishment as part of the proposed LAMP project. An important component of this is the ring RF bunching system at h=1 for one circulating bunch. It has operated with high availability since an upgrade was installed in 1999 to raise the gap voltage*. A second RF system at h=2 is planned to improve the...
We will present the plans and ideas for the next upgrades as discussed for the GANIL-SPIRAL2 installation in France. Recently, a report "French roadmap for Nuclear, Particle, and Astroparticle physics, along with associated technical developments and applications." were produced. It particularly focused to “The future of GANIL”. This was further enriched through extensive discussions by an...
We present a unifying approach to generative deep learning-based 6D phase space diagnostics which combines neural networks, physics models, and adaptive feedback. Our approach includes a physics-constrained neural network (PCNN) for calculating the electromagnetic fields of intense relativistic charged particle beams via 3D convolutional neural networks. Unlike the popular physics-informed...
We present new capabilities in the Neptune electromagnetic particle-in-cell (EM-PIC) simulation code and design environment created to support geometry-based design of high power RF sources. Neptune’s time-domain EM-PIC model to simulate high-voltage, high-current electron beam/RF interactions is a key component of the first-principles design codes created by NRL and Leidos, which provide a...
High Q cavities are an essential component for RF pulse compression. We are interested in developing compact superconducting cavities that operate at high temperature (liquid nitrogen, 80 K). We are designing an RF cavity at 11.424 GHz operating in the TM011 mode using eight facets with flat inner faces. These flat faces will be covered with High Temperature Superconductor (HTS) tapes. The...
We are going to present recent high vacuum pressure measurements recorded at new Prototype Accelerator Module (PAM) of the Advance Sources and Detectors (ASD) – Scorpius project [1]. To avoid the ion-hose instability [2] in our linear inductive accelerator with 2 kA, 20 MeV electron multi-pulse beams during radiographic scans, an advance high vacuum system and accelerator components were being...
Electron cooling of ion beams employing RF-accelerated electron bunches was successfully used for the RHIC physics program in 2020 and 2021. Electron cooler LEReC uses a high-voltage photoemission electron gun with stringent requirements for beam current, beam quality, and stability. The electron gun has a photocathode with a high-power fiber laser, and a novel cathode production, transport,...
A novel deuteron accelerator concept, the deuteron cyclotron auto-resonance accelerator (dCARA) is presented here, with (a) an analytical theory to characterize a simplified model for dCARA, (b) simulated tracks of deuteron orbits in a more realistic model for dCARA, and (c) CST-Studio particle-in-cell simulations for high-current deuteron beams in a realistic dCARA. These predict that dCARA...
Next-generation of synchrotron and FEL X-ray sources will increase the peak power by several orders of magnitude. In these conditions, X-ray intensity will become too severe for the existing materials. Large, single-crystal diamond is one of the few materials suitable for X-ray optical applications due to its unique combination of physical properties. We developed the modified High-Pressure...
The present storage ring of the Siam Photon Source is equipped with the new 118 MHz capacitive type RF cavity, adapted from MAX-IV laboratory. This cavity has been installed in the ring since 2016. The cavity is operated with the digital low level RF controller and the solid-state RF amplifier. The system is running fine with less downtime and maintenance. After the full four insertion devices...
The High-Luminosity LHC project aims to enhance the integrated luminosity of the LHC machine by a factor of 10, by upgrading various components located in the LHC tunnel just before the collision points, with cutting-edge technologies. Among these innovations are the new superconducting magnets equipped with a combination of $Nb-Ti$ and $Nb_3Sn$. conductors. Over 100 magnets are being...
In view of High Luminosity (HL) - Large Hadron Collider (LHC) project, an upgraded collimation system has been developed to accommodate a rise of ten times of the integrated luminosity compared to the LHC. A new series of collimators will be produced and installed in the machine during the Long Shutdown 3 (LS3) to take place during 2026-2028. The updated design incorporates cutting-edge...
The beam produced in the target of the ILC positron source is highly divergent and therefore requires immediate optical matching, conventionally performed by some kind of solenoid arrangement. Recently, the use of a plasma lens has been considered as an alternative with hopes to increase number of positrons available for the downstream acceleration. Previous simulations have indicated that a...
In this work, we will present some recent analysis of the reliability statistics of the CEBAF SRF linac systems. Based on the data collected by the existing Down Time Manager (DTM), the year-to-year downtime evolution trend of linac zones over the six-year period from FY18 to FY23 is established. An in-depth downtime analysis at a resolution beyond the linac zone level was carried out, by...
The Electron Ion Collider (EIC) hadron storage ring (HSR) requires a beam screen made of 75 μm copper layer on top of a 1 mm thick 316LN stainless steel sheet. The eddy currents produced by the dynamic fields at the beam screens of the transition jump quadrupoles will increase the field response delay. The field response curve depends on the thickness and Residual Resistivity Ratio (RRR) value...
The Advanced Light Source Upgrade (ALS-U) is a 4th generation diffraction-limited soft x-ray radiation source. Coupling-impedance-driven instabilities have been carefully evaluated to ensure meeting the machine’s high-performance goals during the design stage. At present, the focus of impedance modeling efforts primarily revolves around supporting beam tests of key components at ALS beamlines...
With Insertion devices adapted to Center of Advanced Microstructures and Devices (CAMD) light source. Injection has more difficulties at low energy. We have proposed some upgrade to the facility, but we would like to look for other choices. In the paper, we will mention the CAMD operation status, discuss raising electron energy method for injection, and simulate the transfer line. The...
This paper will describe efforts to simulate and test materials for the LANSCE PSR stripper foils. Stripper foils convert H- beams to H+ as part of the charge-exchange injection process in the LANSCE PSR that produces high intensity proton beams. The foil properties directly affect the total current and activation in the ring, and their overall robustness also determines the types of...
The impact of high-flux protons on the inherent beam loss in the slow extraction from SPS towards the North Area has been recently discussed and potential improvements have been proposed. These solutions are mainly aiming to reduce the high component activation and related reduction of lifetime, as well as observed non straightness in the anode body. Recent studies have allowed to demonstrate...
The non-evaporable getter (NEG) coatings provide conductance-free evenly distributed pumping, low thermal outgassing rates, second electron yield, and photon-and electron-stimulated desorption. NEG coatings are crucial for achieving ultrahigh vacuum in fourth-generation diffraction storage ring vacuum systems. TiZrV thin films were deposited onto elongated CuCrZr pipes for this investigation....
The intensity of the HL-LHC beam will be twice that of LHC. Hence, an upgrade of the LHC injection kickers (MKIs) is necessary for HL-LHC to avoid excessive beam induced heating of the MKIs. In addition, any newly installed MKI magnet would limit HL-LHC operation for a few hundred hours due to dynamic vacuum activity. Extensive studies have been carried out to identify solutions to address...
Recent progress of basic study on Harmonic nonlinear Compton scattering in Brookhaven National Laboratory Accelerator Test Facility (BNL ATF) will be reported. Experiment is conducted by counter collision of a multi TW CO2 laser and 60-70 MeV electron beam having 300-600 pC of charge per pulse. Experiment AE131 is intended for two aspects of experimental demonstrations. A: Nonlinear bi...
A 4th generation storage ring based light source is being developed in Korea since 2021. It features <100 pm rad emittance, about 800 m circumference, 4 GeV e-beam energy, full energy booster injection, and more than 40 beamlines which includes more than 24 insertion device (ID) beamlines. For extraction/injection to the booster and storage ring, it needs 4 septums, and 6 kickers....
This research presents a framework for the application of Reinforcement Learning (RL) to optimize the injection process at particle accelerator facilities. By utilizing a tailored and enhanced RL agent, we demonstrate its capability to dynamically optimize the beam's cross-section to meet predefined targets effectively at the Cooler Synchrotron COSY facility in Jülich, Germany. The agent,...
The Rapid Cycling Synchrotron (RCS) at the China Spallation Neutron Source phase II (CSNS-II) is a high intensity proton accelerator, which accumulates a 300 MeV proton beam and accelerates it to 1.6 GeV with a repetition rate of 25 Hz. The CSNS-II is designed to have a beam power of 500 kW. A circulated beam intensity current in the RCS is 15 A, making it the highest of its kind in the world....
Taiwan Photon Source (TPS) is a 3 GeV synchrotron light source at the National Synchrotron Radiation Research Center (NSRRC) in Taiwan. Several in-vacuum undulators are expected to be installed before the end of 2024. Before installation in the storage ring, an in-vacuum undulator's magnetic field has been measured at operational gaps. In order to assess the performance of the in-vacuum...
The CERN Proton Synchrotron Booster (PSB) was upgraded within the LHC Injectors Upgrade (LIU) project and delivers a large variety of high-intensity beams for fixed target experiments and high-brightness beams for collisions at the LHC. In the context of the Physics Beyond Colliders (PBC) study and of a possible upgrade of the ISOLDE experimental area, intensities up to 1500×1e+10 particles...
Fixed target beams are extracted in five turns from the Proton Synchrotron (PS) at CERN to fill almost half the circumference of the Super Proton Synchrotron (SPS) with each transfer. To avoid beam loss during the risetime of the extraction kickers a longitudinal gap is generated with an RF barrier-bucket scheme. However, the synchronization of the gap with the PS extraction and SPS injection...
In this study, we present the design of a candidate lattice for the Shanghai Synchrotron Radiation Facility Upgrade (SSRF-U) storage ring, targeting the soft X-ray diffraction limit. Due to its ultra-low emittance, intra-beam and Touschek scattering are significant and require attention. We conducted simulations to examine the emittance growth and beam lifetime of different machine...
In the framework of the SABINA project (Source of Advanced Beam Imaging for Novel Applications), a new Free Electron Laser line will be realized at the Laboratori Nazionali di Frascati (LNF). It will be based in the SPARC_LAB laboratory with the purpose to supply radiation in the Thz/MIR range to external user. The line layout foresees two correctors between the three APPLE-X undulators...
The Taiwan photon source (TPS), a synchrotron accelerator at the National Synchrotron Radiation Research Center in Taiwan, is a third-generation accelerator operating at 3 GeV that was designed to create a high energy photon source. The TPS front-end (FE) systems are located between the storage ring and beamline, which was designed to protect the safety of users as well as control experimental...
The Karlsruhe Research Accelerator (KARA) is a synchrotron light source user and test facility, operating at an electron beam energy ranging from 0.5 to 2.5 GeV. Performing optics measurements and comparing with the machine model promises an improved understanding of the lattice and the underlying beam dynamics. Horizontal and vertical turn-by-turn Beam Position Monitor data are acquired and...
Los Alamos Neutron Science Center (LANSCE) relies on 44 klystron modulator systems to feed the accelerating cavities and produce proton beam of 800 MeV. This paper focuses on the new VA-862A1 86kV 1.25 MW klystron units and aims to compare their performance with previously purchased units. Service hours for each klystron unit was used as the primary metric in the analysis and records from...
The LHC Abort Gap Monitor (AGM) is part of the LHC machine protection system (MPS) and is designed to measure the particle population in a 3us wide region known as the "abort gap." This region needs to be kept empty to ensure safe beam dumps. The AGM captures the synchrotron light generated in the visible part of the spectra and converts it into an electric signal. This signal is then...
Laser plasma acceleration (LPA) technology is advancing day by day, getting ready for user facility applications. LPA might be applicable to a generation of electron beams directly within the light-source storage-ring vacuum chamber. Typical injector of the light source facility consists of linac and synchrotron booster (or simply a full energy linac). It can be replaced by a laser plasma cell...
Here, we introduce Linac_Gen, a tool developed at Fermilab, which combines machine learning algorithms with Particle-in-Cell methods to advance beam dynamics in linacs. Linac_Gen employs techniques such as Random Forest, Genetic Algorithms, Support Vector Machines, and Neural Networks, achieving a tenfold increase in speed for phase-space matching in Linacs over traditional methods, through...
Seeking non-invasive beam profile monitoring for the Iranian Light Source Facility (ILSF), we propose a novel approach based on the utilization of Smith-Purcell, transition, and diffraction radiation. The ILSF is a synchrotron radiation facility with a storage ring capable of providing electron bunches up to 3 GeV. The Smith-Purcell radiation is generated when a charged particle passes over a...
MedAustron is an ion therapy facility located in Wiener Neustadt, Austria, which uses third order resonant slow extraction to deliver protons and carbon ions for clinical irradiation. The foreseen upgrade of the new low level RF (LLRF) system facilitates advanced longitudinal beam manipulation schemes involving multiple RF harmonics, which will be exploited to improve the slow extraction...
We present an approach for detection of anomalies in the temperatures of magnet power supplies (PSs) in storage rings. We train a Long Short-Term Memory (LSTM) neural network to predict the temperatures of several components of a PS (heatsinks, capacitors, resistors) based on the PS current, PS voltage, and room temperature. An anomaly is detected when the observed PS temperature starts to...
Efficient control of frequency detuning for the radio-frequency quadrupole (RFQ) at the Facility for Rare Isotope Beams (FRIB) is still challenging. The transport delay and the complicated heat transfer process in the cooling water control system convolute the control problem. In this work, a long-short term memory (LSTM)-based Koopman model is proposed to deal with this time-delayed control...
An MeV ultrafast electron diffraction (MUED) in-strument system is a unique characterization technique used to study ultrafast processes in a variety of mate-rials by a pump-probe method. Combining this tech-nology with rapid data science and artificial intelli-gence/machine learning (AI/ML) technologies in con-junction with high-performance computing can create a turnkey, automated...
At a heavy ion linac facility, such as ATLAS at Argonne National Laboratory, a new ion beam is tuned once or twice a week. The use of machine learning can be leveraged to streamline the tuning process, reducing the time needed to tune a given beam and allowing more beam time for the experimental program. After establishing automatic data collection and two-way communication with the control...
Accurate knowledge of beam parameters is essential for optimizing the performance of particle accelerators like the Large Hadron Collider (LHC). An initial machine-learning (ML) model for the reconstruction of the longitudinal distribution has been extended to extract the main parameters of multiple bunches at LHC injection. The extended model utilizes an encoder-decoder architecture to...
Prior to assembly into the operational cryostat each superconducting undulator (SCU) at the Advanced Photon Source undergoes testing in a LHe bath cryostat where coil training and magnetic measurements are performed. If necessary, the baseline magnetic measurements are used for phase error tuning which is achieved by adjusting the magnetic gap of the SCU at prescribed locations. An...
We developed a magnetic compression method for relativistic electron beam macro-pulses. Our device, with a significantly larger transfer function R56 compared to the classical chicane structure, enables nanosecond-scale compression of relativistic electron pulses using a compact apparatus measuring just a few meters. This paper introduces the principles of this compression method and presents...
The ESRF-EBS injection is performed with a standard off-axis injection scheme consisting of two in-air septa S1/2, one in vacuum septum S3 and four kicker magnets K1 to K4 to generate the injection bump. We can achieve 80% efficiency with this scheme. Despite many modifications and adjustments which allow the reduction of the perturbation, some beamlines are still affected. The Non-Linear...
Compact synchrotrons, such as those proposed for cancer therapy, use short and highly bent dipoles. Large curvature drives non-linear effects in both body and fringe fields, which may be critical to control to obtain the desired dynamic aperture. Similarly to current practice, for straight magnet, our long-term goal is to aim at finding a parametrization of the field map that requires few...
An Argonne-SLAC collaboration is working on the design of a superconducting undulator (SCU) demonstrator for a free-electron laser (FEL)*. A SCU magnetic structure consisting of a 1.5-m-long planar SCU magnet, and a superconducting phase shifter have been designed. A novel three-groove correction scheme has been implemented for the SCU magnet. A compact four-pole phase shifter with magnetic...
Transparent off-axis injection in a storage ring by means of a non-linear kicker requires tight field tolerances at the limit of modern technique. To characterize the field profile of the non-linear kicker under development for the ALBA-II storage ring, a dedicated measurement bench based on a variant of the vibrating wire technique was developed. The small size and limited weight of the...
Beam profile measurements in the LHC and its injector complex show heavy tails in both transverse planes. From standard profile measurements, it is not possible to determine
if the underlying phase space distribution is statistically independent. A measurement campaign in the CERN PSB was carried out to introduce cross-plane dependence in bunched beams in controlled conditions, in view of...
Hadron therapy uses scanning magnets to precisely deliver therapeutic beams, minimizing the damage to healthy tissues and reducing side effects. A collaboration between CNAO, CERN, INFN and MedAustron is developing an innovative gantry design with superconducting magnets and a downstream scanning system. The project features two compact scanning dipoles, each with a central field of 1 T –...
The Advanced Photon Source (APS) facility has just completed an upgrade to become one of the world’s brightest storage-ring light sources. For the first time, machine learning (ML) methods have been developed and used as part of the baseline commissioning plan. One such method is Bayesian optimization (BO) – a versatile tool for efficient high-dimensional single and multi-objective tuning, as...
Klystrons and Multiple-Beam Klystrons (MBKs) are widely used or proposed to be used in accelerators as high-power RF sources. Development and optimization of klystron and MBK’s designs is aided by the use of different simulation tools, including highly efficient large-signal codes. We present an overview of capabilities of the TESLA-family of 2.5D large-signal codes, which have been developed...
Industrial accelerator applications require efficient, scalable, continuous wave (CW) microwave power systems. Magnetrons are inexpensive and efficient devices for converting electrical energy into microwave power; however, their power output is limited to approximately 100 kW. Cost effective power combining magnetron systems would serve the accelerator industry by providing practical and...
National Synchrotron Radiation Center SOLARIS operates a third-generation synchrotron light source located in Krakow, Poland. It is the only operator of synchrotron light source in Poland. SOLARIS accelerator complex consists of a linear accelerator, 1.5 GeV storage ring with 96 m circumference, six operating beamlines and three more under construction. The storage ring accelerates the...
Modification of an arc-cell vacuum system (length 14 m) for the cell SR18 in the TPS storage ring is described, which includes (a) replacement of a new bending chamber (B1) with an increased vertical aperture from 9 to 18 mm to prevent the B1 chamber from being exposed to synchronous radiation from the upstream elliptically polarized undulator (EPU), and (b) incensement of three pairs of...
In the storage rings, the electron beams go to the equilibrium state. One of the equilibrium parameters is the natural emittance which is determined by the radiation damping and quantum excitation effects. In other words, the equilibrium emittance is determined by the magnet lattice regardless of the initial beam. Theoretically the minimum emittance and its optimal conditions for uniform...
The Cool Copper Collider (C3) is a novel accelerator concept for a linear collider utilizing a cryogenically-cooled copper linear accelerator (linac) with a distributed coupling architecture. The C3 main linac is designed to accelerate electron/positron from 10 GeV to 125 GeV while preserving the beam emittance. Here we present the analysis of the multi-bunch beam dynamics for the C3 main...
RadiaBeam is developing and manufacturing a 15-mm period, 1.15 T high temperature superconductor undulator using Magnesium Diboride (MgB2) wire to operate in a temperature range of 10 K - 15 K. This temperature range can be achieved by a cryocooler, a simpler and less expensive cryogenic solution compared to a liquid helium approach. As the supported current density, and ultimately the quench...
Increase of primary beam power for neutrino beam-lines leads to a reduced lifespan for production targets. New concepts for robust targets are emerging from the field of High Power Targetry (HPT); one idea being investigated by the HPT R&D Group at Fermilab is an electrospun nanofiber target. As part of their evaluation, samples with different densities were sent to the HiRadMat facility at...
The accelerator network of the Pohang Accelerator Laboratory (PAL) was initially designed and installed in 2015. It consists of three types of networks: a Public Network for external internet access, an Operation Network for accelerator operation and overall control, and a Control Network for device control and monitoring.
From a hardware perspective, it comprises 2 firewalls, 1 intrusion...
The Innovation Fostering in Accelerator Science and Technology (I.FAST) project aims to enhance innovation in the particle accelerator community, mapping out and facilitating the development of breakthrough technologies common to multiple accelerator platforms. Task 7.2 of the I.FAST project, Enabling Technologies for Ultra Low Emittance Rings, focuses on networking in the area of low...
Numerical optimizations on couplers of the traveling wave accelerating structures usually require lots of calculation resources. This paper proposes a new technique for matching couplers to an accelerating structure in a more efficient way. It combines conventional Kroll method with improved Kyhl method, thereby simplifying the tuning and simulation process. We will present the detailed design...
The alignment installation work of Hefei Advanced Light Facility (HALF) is usually carried out in tunnels. Calculate the key component points to the global coor-dinate system through coordinate conversion, and accu-rately adjust them to the corresponding coordinate values for alignment and installation. However, long and narrow tunnels can easily cause dense common points, resulting in a loss...
To meet phase stability requirements, a high peak power coaxial magnetron-based RF system with >70% efficiency would normally be injection locked to an RF source by using a circulator to send the locking signal into the magnetron through the antenna. This added requirement of a high-power circulator pushes the inherently low coaxial magnetron’s cost-per-watt to a high overall RF Power Source...
The Shanghai Light Source has been operated since 2009 to provide synchrotron radiation to 40 beamlines of the electron storage ring at a fixed electron energy of 3.5 GeV. The Shanghai Laser Electron Gamma Source (SLEGS) is approved to produce energy-tunable gamma rays in the inverse Compton slant-scattering of 100 W CO2 laser on the 3.5 GeV electrons as well as in the back-scattering. SLEGS...
NanoSonic has demonstrated advanced high radiation durable composite and polymeric materials for applications in radio frequency devices, cryomodule gate valves, and seals for beam dumps. Through additive and scalable manufacturing techniques, the novel radiation tolerant polymers for use within accelerator components and subsystems have shown potential to replace current state of the art...
The design performance of the 3.5 GeV Diamond-II low-emittance electron storage ring has been studied as a function of the linear and nonlinear lattice tuning parameters. An alternative working point has been identified which optimizes the beam lifetime and the injection efficiency for off-axis injection. The simulations include misalignment and field strength errors, with the number of...
This paper discusses the mechanism of emittance growth and beam loss arising from magnetic field ripples in J-PARC MR, based on numerical simulations supported by beam experiments.
The European Synchrotron Radiation Facility - Extremely Brilliant Source (ESRF-EBS) is a facility upgrade allowing its scientific users to take advantage of the first high-energy 4th generation storage ring light source. In December 2018, after 30 years of operation, the beam stopped for a 12-month shutdown to dismantle the old storage ring and to install the new X-ray source. On 25th August...
The National Synchrotron Radiation Research Center (NSRRC) has developed a 300 kW solid-state amplifier. This 300 kW solid-state amplifier RF transmitter has been operating continuously since August 2023, consistently delivering an output of 250 kW RF power during user beam time at 500 mA. This report describes the performance of the solid-state amplifier RF transmitter during this period,...
The synchrotron SOLEIL is the French third-generation 2.75 GeV synchrotron light source, a research laboratory at the forefront of experimental techniques for the analysis of matter down to the atomic level, and a service platform open to all scientific and industrial communities. We present the performance of the accelerators, which deliver extremely stable photon beams to 29 beamlines. We...
A novel mechanism, known as steady-state microbunching (SSMB), is anticipated to produce light with high peak brilliance and a high repetition rate by integrating the characteristics of free electron lasers and synchrotron radiation facilities. This paper presents the status of a high-finesse prototype optical enhancement cavity designed for SSMB, achieving an average power of 55 kW. The...
The High Intensity ECN3 (HI-ECN3) study project aims to increase the intensity of the proton beam delivered to a new experimental facility housed in the ECN3 underground cavern in CERN’s North Area up to the ~4e+13 ppp (protons per pulse) and up to ~4e+19 POT (protons on target) per year. The increase necessitates upgrades of the primary beam transfer lines coming from SPS directly to the new...
It is currently planned to increase the energy of the CEBAF recirculating linear accelerator to 20 GeV or more by adding two new recirculating arcs that contain multiple new energy passes. The beam is continuous (CW), so no field ramping is desired, making this a fixed-field accelerator (FFA). The wide energy range requires a low dispersion lattice that can be created with high-gradient...
The LBNF Absorber consists of thirteen 6061-T6 aluminum core blocks. The core blocks are water cooled with de-ionized (DI) water which becomes radioactive during beam operations. The cooling water flows through gun-drilled channels in the core blocks. A weld quality optimization was performed to produce National Aeronautical Standard (NAS) 1514 Class I [1] quality welds on the aluminum core...
The RHIC heavy ion program relies on a series of RF bunch merge gymnastics to combine individual source pulses into bunches of suitable intensity. Intensity and emittance preservation during these gymnastics require careful setup of the voltages and phases of RF cavities operating at several different harmonic numbers. The optimum setting tends to drift over time, degrading performance and...
The Electron-Ion Collider (EIC) Hadron Storage Ring (HSR) will use strong hadron cooling to maintain the beam brightness and high luminosity during long collision experiments. An Energy Recovery Linac is used to deliver the high-current high-brightness electron beam for cooling. For the best cooling effect, the electron beam requires low emittance, small energy spread, and uniform longitudinal...
Nanostructures are currently attracting attention as a medium for obtaining ultra-high-density plasmas for beam-driven or laser-driven acceleration. This study investigates Bayesian optimization in Laser Wakefield Acceleration (LWFA) to enhance solid-state plasma parameters towards achieving extremely high gradients on the order of TV/m or beyond, specifically focusing on nanostructured...
The Future Circular electron-positron Collider, FCC-ee, is a design study for a 90 km circumference luminosity-frontier and highest-energy e+e- collider. It foresees four operation modes optimized for producing different particles by colliding high-brightness lepton beams. Operating such a machine presents unique challenges, including stored beam energies up to 17.5 MJ, a value about two...
For a large ring, the response matrix contains tens of thousands of data points, allowing for a comprehensive representation of the ring’s linear optics. However, when it comes to fourth-generation diffraction-limited rings that utilize strong sextupoles and octupoles, the response matrix derived from closed orbit tracking is significantly influenced by nonlinearity. This nonlinearity poses...
During the coherent electron cooling (CeC) experiment at RHIC, we have encountered various challenges to align the electron beam both in the low energy beam transfer line and in the cooling section. For example, the electrons exit the SRF gun with an orbital angle of tens of milli-radian, which is likely caused by the misalignment of the cavity inside the cryostat and the tilted cathode. The...
The Advanced Light Source (ALS) storage ring employs various feedback and feedforward systems to stabilize the circulating electron beam thus ensuring delivery of steady synchrotron radiation to the users. In particular, active correction is essential to compensate for the significant perturbations to the transverse beam size induced by user-controlled tuning of the insertion devices, which...
The Fermilab Accelerator Science and Technology (FAST) facility is dedicated to the exploration of novel concepts in accelerator and beam physics, and the development of a robust workforce, in order to enable and enhance next-generation particle accelerators. FAST comprises a high-brightness superconducting electron linac, and a storage ring, the Integrable Optics Test Accelerator (IOTA)....
The parallel beam based alignment technique developped at SLAC is applied for the EBS storage ring. The results are compared with the standard beam based alignment technique used for operation.
At the Argonne (ANL) Advanced Photon Source (APS), a 425-MeV Particle Accumulator Ring (PAR) is used to stack 1-nC electron pulses from the linac and inject a single bunch into the booster at a 1-Hz repetition rate. All the APS injectors, including PAR, were shut down in April 2023 at the start of the APS Upgrade Dark Time. In this paper, we report on PAR re-start activities starting in Oct....
Interaction of intense laser pulses with plasma finds one of the important applications in acceleration of charged particles. The pioneering work of Tajima and Dawson [1] has given great impetus to the idea of electron acceleration using wakefield generated by intense laser pulses. Acceleration of electrons by enhanced wakefield generated by chirped laser pulse propagating together in plasma...
NSLS-II is a 3 GeV third generation synchrotron light source at BNL. The storage ring was commissioned in 2014 and began its routine operations in the December of the same year. Since then, we have progressed steadily upwards in beam current and reached 500 mA in five years while continue to install and commission new insertion devices. Along this path, we met various challenges. In this...
Fermilab is currently engaged in the development of an 800 MeV superconducting RF linac, aiming to replace its existing 400 MeV normal conducting linac. PIP-II is a warm front-end producing 2 mA of 2.1 MeV H-, followed by a sequence of superconducting RF cryomodules leading to 800 MeV. To mitigate potential damage to the superconducting RF cavities, PIP-II uses laser-based monitors for beam...
A double-crystal fixed-target experiment is planned for installation in CERN’s Large Hadron Collider (LHC). This experiment features a 7 cm-long bent silicon crystal, with 7 mrad bend-angle to deflect particles produced by proton interactions with a target. As this crystal is more than an order of magnitude longer than any other installed in the LHC, it requires specific characterization,...
A 500 MHz normal-conducting (NC) cavity is being developed for Super Tau-Charm Main Rings which have a current of 2 A and a synchronous radiation energy loss of 410 keV per turn. This NC cavity operates in a higher order mode of TM020. Through optimizations, it results in a high quality factor and a low R/Q. This feature is beneficial to reduce the required detuning frequency so that the...
The Normal-Conducting Radio-Frequency (NCRF) systems for the Electron-Ion Collider Hadron Storage Ring (EIC HSR) consist of 4 unique cavity resonators. The HSR NCRF systems are composed of a 24.6 MHz capture and acceleration system, a combined 49.2 MHz and 98.4 MHz bunch splitting system, and a 197 MHz storage system for collider operations. This paper presents the preliminary design of the...
A new project is underway to develop the successor to the current Australian Synchrotron. The new storage ring is proposed to be 455 m in circumference operating at 3 GeV. A preliminary 7BA lattice has been designed which utilizes the higher-order achromat (HOA) scheme to suppress strong sextupole driving terms. The lattice has 24 sectors and a natural horizontal emittance of 50 pm-rad. This...
Reinforcement Learning (RL) has demonstrated its effectiveness in solving control problems in particle accelerators. A challenging application is the control of the microbunching instability (MBI) in synchrotron light sources. Here the interaction of an electron bunch with its emitted coherent synchrotron radiation leads to complex non-linear dynamics and pronounced fluctuations.
Addressing...
The Eupraxia@SPARC_LAB project involves the development of a 1 GeV normal conducting Linac with an S-band injector followed by an X-band booster. To achieve the final energy, the booster consists of 16 traveling wave accelerating structures operating at 11.994 GHz with a minimum working gradient of 60 MV/m. An intensive design activity, prototyping, and testing of these structures is underway...
The Hefei Advanced Light Facility (HALF) is a diffraction-limited storage ring with a 2.2 GeV energy and modified 6BA lattice that is currently under construction. To meet the requirement for high-brightness hard X-rays, it is being considered that superconducting longitudinal gradient bend will replace ordinary longitudinal gradient bend in some cells in the future. Based on the measured...
Two synchrotron radiation sources, the 2.5 GeV Photon Factory Storage Ring (PF ring) and the 6.5 GeV Photon Factory Advanced Ring (PF-AR), have been in stable operation at the High Energy Accelerator Research Organization (KEK) for over 40 years. This paper first describes the current operational status and recent developments at PF. Next, a new concept of hybrid light source (PF-HLS)...
The Advanced Photons Source (APS) storage ring (SR) underwent an upgrade to the multi-bend achromat (MBA) lattice recently. As part of the upgrade, four out of the sixteen Radio Frequency (RF) cavities were removed from the storage ring. The remaining twelve cavities were left in place during the entire upgrade process and restored to full operating power to support beam commissioning once the...
Fast single-turn injection kicker systems deflect incoming beam onto the orbit of the LHC. The higher intensities of High Luminosity (HL) LHC beams are predicted to cause the ferrite yokes of the LHC injection kicker magnets (MKI), in their current configuration, to heat up to their Curie temperature. Studies to reduce the beam induced heating have been carried out over the past years and...
In this paper we discuss the latest developments for the FCC-ee interaction region layout, which represents one of the key ingredients to establish the feasibility of the FCC-ee. The collider has to achieve extremely high luminosities over a wide range of center-of-mass energies with two or four interaction points. The complex final focus hosted in the detector region has to be carefully...
The High Energy Photon Source (HEPS) is a 34-pm, 1360-m storage ring light source being built in the suburb of Beijing, China. The HEPS construction started in 2019, with the main civil construction finished at the end of 2021. In the past year, the beam commissioning of the HEPS injector (both Linac and booster) was started and had been finished, and the equipment installation was underway...
Advances in high-performance computing have enabled detailed physics simulations, including those with nonlinear collective effects such as space charge, to be deployed online in a control room setting to aid operator intuition and be used directly in automatic tuning. Simultaneously, machine learning (ML) has enabled deployment of detailed models online with sub-second execution time, opened...
The magnetron as an efficient RF source for a compact industrial SRF accelerator has been proposed [1]. The performance of injection phase lock on two independent magnetron transmitters operated at 915 MHz, in CW mode with maximum power of 75 kW each has been demonstrated to satisfy for this application [2]. This industrial type magnetron has transformer and SCR rectifier on the DC anode power...
The electron-ion collider (EIC) at Brookhaven National Laboratory (BNL) is designed to deliver a peak luminosity of 1e+34 1/cm2 1/sec. The EIC will take advantage of the existing Relativistic Heavy Ion Collider (RHIC) facility. Two additional rings will be installed: an electron storage ring (ESR) and a rapid cycling electron synchrotron ring (RCS).
This paper presents an update on the normal...
The Proton Power Upgrade project at the Spallation Neutron Source at Oak Ridge National Laboratory will increase the proton beam power capability from 1.4 to 2.8 MW. Upon completion in early 2025, 2 MW of beam power will be available for neutron production at the existing first target station (FTS) with the remaining beam power available for the future second target station (STS). The project...
Paul Scherrer Institute (PSI) has led significant advancements in accelerator electronics development, leveraging Field Programmable Gate Arrays (FPGA) based Digital Signal Processing (DSP) across various critical systems, including Low Level RF (LLRF), Longitudinal Beam Loss Monitoring (LBLM), charge particle measurement via Integrating Current Transformers (ICT), Timing, Filling Pattern...
The Physics Beyond Colliders is a CERN exploratory study aimed to fully exploit the scientific potential of its accelerator complex. In this initiative, the Gamma Factory experiment aims to produce in the Large Hadron Collider (GF@LHC) high-intensity photon beams in the energy domain up to 400 MeV. The production scheme is based on the collisions of a laser with ultra-relativistic atomic beam...
Picosecond-long x-ray pulses of moderate intensity and high repetition rate are highly sought after by the light source community, especially for time-resolved fine spectroscope analysis of matter in the linear response regime. As part of the upgrade of the Elettra 2.0, two radio frequency deflecting cavities will be installed to produce time-dependent orbit deflection to a few dedicated...
The penetrating radiography provided by the Dual Axis Radiographic Hydrodynamic Test (DARHT) facility is a key capability in executing a core mission of the Los Alamos National Laboratory (LANL). Historical data from the two DARHT Linear Induction Accelerators (LIAs), built as hdf5 data structures for over a decade of operations, are being used to train machine learning models to assist in...
At the CERN Large Hadron Collider (LHC), bent crystals play a crucial role in efficiently redirecting beam halo particles toward secondary collimators used for absorption. This innovative crystal collimation method leverages millimeter-sized crystals to achieve deflection equivalent to a magnetic field of hundreds of Tesla, significantly enhancing the machine’s cleaning performance...
Generating low emittance electron bunches from the photocathodes backing free-electron lasers (FEL) is a potential source of significant improvement in achievable X-ray peak powers. Temporally shaping the photoexcitation lasers with intensity profiles that are perfectly flattop or ellipsoidal has been demonstrated to improve the emittance of the emitted electron bunch. However, experimental...
Laser wire has been used for nonintrusive profile and emittance measurements of operational hydrogen ion (H-) beam at the SNS linac. In this talk, we will describe the following recent developments in the laser wire system. 1) An upgraded light source and laser transport line which enables novel measurement capabilities including longitudinal profile measurement and high-energy proton beam...
The non-evaporable getter (NEG) film deposited on the inner wall of the vacuum chamber using magnetron sputtering has been widely used in the fourth-generation synchrotron radiation light source to obtain and maintenance ultra-high vacuum in narrow vacuum chambers. The IAU vacuum chamber has a small cross-sectional size and a long length . It also needs to deposit a NEG film to meet the...
Research on a novel permanent quadrpole magnet (PQM) design is introduced in this paper. It can make the quadrupole magnetic field gradient continuously adjustable by modulating several permanent magnet blocks. Four poles of the magnet inform an integral whole to ensure good structural symmetry, which is essential to obtain high-quality quadrupole magnetic field permanent quadrupole magnet....
Recently the need has arisen to examine the effects of a variable coupling factor in the complex baseband RF cavity model. This paper briefly reviews the dynamic baseband model, then augments the model to include variable coupling. Power balance, asymptotic behavior and model simplifications are explored. Finally, applications of high-power RF pulse compression and transient heating in...
Pulse compressors have been widely used to generate very high peak RF power in exchange for a reduction in the RF pulse length for linear accelerators. A C-band spherical pulse compressor is numerically studied for the linac of Super Tau-Charm Facility in this paper. Utilizing a dual-mode coupler for producing two orthogonal polarized TE11 modes, TE114 mode is chose for storing energy in...
In the framework of EuPRAXIA@SPARC_LAB project, we are studying possible solutions to upgrade and measure the amplitude and phase stability of the RF accelerating fields generated by a klystron. These studies concern the C- and X- band klystrons installed in the LNF infrastructures. In particular, we will present our work on a fast phase feedback around the C-band power station (50 MW klystron...
The J-PARC Main Ring accelerates proton beam from 3 GeV to 30 GeV and delivers it to T2K neutrino experiment with fast extraction and hadron experiments with slow extraction. In the last two years the beam power to the neutrino experiment was increased from 500 kW to 750 kW. The T2K detector is scheduled to be replaced by the new Hyper-K detector; the latter will be able to accept a 1.3 MW...
ROCK-IT aims to develop a demonstrator for automation and remote-access to beamlines of synchrotron radiation facilities. The four participating Helmholtz centers DESY, HZB, HZDR, and KIT have identified catalysis operando experiments as a pilot development. So far, no automation exists for such experiments and since the optimization of catalysts requires to evaluate a large parameter space of...
The High Luminosity Large Hadron Collider (HL-LHC) project seeks to significantly enhance the performance of the LHC to deliver ten times more data to the LHC Experiments. The project relies on cutting-edge systems and technologies deployed in the new facilities constructed to the HL-LHC requisites and replacing large existing equipment and systems in the LHC tunnel. The project complexity...
The East Area at the Proton Synchrotron has undergone extensive renovations, marking a significant milestone in its more than 55-year history as one of CERN’s enduring facilities for experiments, beam tests, and irradiation. This facility, which serves over 20 user teams for about 200 days annually, now boasts an enhanced infrastructure to cater to future beam test and physics requirements. It...
The Rapid Cyclotron Synchrotron (RCS) is an acceleration ring designed for boosting the electron energy from 400 MeV after the LINAC to 1 GeV prepared for injection into the Electron Storage Ring (ESR). Operating in a pulsed mode at 1 Hz, the RCS accelerates four consecutive bunches with dipole magnet ramping rapidly at each injection. Rapid ramping of the magnetic field induces eddy currents,...
A setup of in-house made Goubau (G-) Line system for measuring the broadband impedance of vacuum components has been developed at the NSRRC for improving the beam-stability of the Taiwan Photon Source (TPS). A thin copper wire of 0.287 mm in diameter with polyimide-coating ~0.02 mm in thickness connects two horn-shape aluminum launchers face-to-face at a distance ~1.2 m far in between via two...
The nonlinear integrable optics studies at the integrable optics test accelerator (IOTA) demand fine control of the chromaticity using sextupole magnets. During the last experimental run undesirable misalignments and multipole composition in some sextupole magnets impacted operations. This report outlines the beam-based methods used to identify the nature of the misalignments and defects, and...
During the Long Shutdown 2, the two internal dumps were replaced and successfully integrated into the CERN Proton Synchrotron operation to withstand the intense and bright beams for the High-Luminosity LHC. They function as safety devices, designed to swiftly intersect the beam’s trajectory and effectively stop the beam over multiple turns. A significant challenge arises from their limited...
Muon colliders hold promise for high luminosity multi-TeV collisions, without synchrotron radiation challenges. However, this involves investigation into novel methods of muon production, acceleration, cooling, storage, and detection. Thus, a cooling demonstrator has been proposed to investigate 6D muon ionization cooling. The MICE experiment validated ionization cooling to reduce transverse...
An 820 mA CW positive ion source is being developed to produce Mo-99 using the fusion of deuterium and tritium ion beams on a rotating target to produce neutrons for use in the production of radiopharmaceuticals. The ion source consists of an RF plasma source, a multi-aperture extractor, and 300 kV accelerating column. This paper will describe a simulation study of the beam through the...
GL2000 Gabor-lens (GL)[1, 2] is a 2-m long device constructed and successfully operated at Goethe University. The confined electron column is much longer compared to previous constructed lenses and offers unique opportunity for investigation of electron cloud dynamics. Especially, kind of fingertip stopband structures were precisely measured in production diagram (operation function) in the...
Coherent electron cooling (CeC) is a novel technique for rapidly cooling high-energy, high-intensity hadron beam. Plasma cascade amplifier (PCA) has been proposed for the CeC experiment in the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL). Cooling performance of PCA based CeC has been predicted in 3D start-to-end CeC simulations using code SPACE. The dependence...
The Electron Ion Collider calls for collisions of helion beam on polarized electron beams. Polarized helions will be injected into the Hadron Storage Ring at |Gγ| = 49.5 and have a maximum energy corresponding to |Gγ| = 820. Simulations of helions in this energy range have been performed using zgoubi. These studies quantify the polarization transmission with six snakes and also categorize the...
The proposed ten-pass energy recovery linac (ERL) demonstration (five accelerating, five decelerating) at the CEBAF accelerator, ER@CEBAF, involves a multi-GeV energy
range of a continuous electron beam. New CEBAF transverse optics were designed for this ERL demonstration. This redesign incorporates additional components in Arc A, including a path length chicane and new quadrupoles to ensure...
Scraping the beam in an electron storage ring while counting photons of synchrotron radiation is a well-known technique to produce a beam of a single or a few electrons which enables new experimental opportunities compared to standard accelerator physics. Synchrotron radiation is usually described as an electromagnetic wave in the frame of classical electrodynamics. The emission of photons by...
A cavity-based x-ray free-electron laser (CBXFEL) is a possible future direction in the development of fully coherent hard x-ray sources of high spectral brilliance, a narrow spectral bandwidth of ~1-100 meV, and a high repetition rate of ~1 MHz. A diagnostic tool is required to measure CBXFEL spectra with a meV resolution on the shot-to-shot bases. Here we present test results of a single...
In SIS18 U²⁸⁺ is used to reach highest heavy ion beam intensities for FAIR-operation. The medium charge state avoids losses during stripping processes and shifts the space charge limit to higher number of particles. Nevertheless, these ions are subjected to ionization loss in collisions with residual gas particles. Via ion impact induced gas desorption a feedback between vacuum quality and...
The CERN Super Proton Synchrotron (SPS) offers slow-extracted, high-intensity proton beams at 400 GeV/c for 3 fixed targets in the CERN North Experimental Area (NA) with a spill length of about 5 seconds. Since first commissioning in the late seventies, the NA has seen a steady increase in users, many of which requiring improved spill quality control. Slow extraction is sensitive to small...
Recently, the heavy ion synchrotron SIS18 at GSI was for the first time operated with a dual-isotope beam, made up of 12C3+ and 4He+. Such a beam can be used to improve carbon radiotherapy by providing online information on dose deposition, where the helium ions serve as a probe beam traversing the patient while depositing a negligible dose. For this, the accelerator has to deliver a slowly...
Pairs of Siberian Snakes allow the avoidance of first-order spin resonances during energy ramping. However, a high density of first-order resonances correlates with the presence of higher-order resonances after the installation of snakes. Thus, one effective tactic of mitigating higher-order resonances is by weakening the surrounding first-order ones, equivalent to minimizing the spin-orbit...
The BEam COoler and LAser spectroscopy (BECOLA) is a collinear laser spectroscopy facility at the Facility for Rare Isotope Beams (FRIB) at Michigan State University. Time resolved laser spectroscopy experiments are performed here to study the nuclear structure of radioactive isotopes. The current data acquisition (DAQ) system being used is based on AMD Spartan 6 field programmable gate array...
A failure of the RHIC powering system occurred at the end of run 23 and led to the discovery of ruptured con-ductors on the 12x150A current leads used to feed cur-rent to the superconducting (SC) magnet circuits. These ruptured conductors are thought to have led to an electri-cal breakdown, first within the solder joint, and then across adjacent conductors of the same current lead assembly. A...
SOLEIL II is the French upgrade project to build the science of tomorrow with synchrotron light radiation. Providing the highest brilliance in its class while maintaining the radiation range from IR to hard X-rays, the project is an ambitious triple upgrade of the SOLEIL facility: accelerators (new booster and storage ring), 29 beamlines and 3 laboratories, and an information technology...
The Advanced Photon Source at Argonne National Laboratory (ANL) is in the process of acquiring solid state amplifiers (SSA) from R&K Limited to replace four 1MW klystron rf systems that provide rf power to the storage ring cavities. This project is necessary primarily due to klystron obsolescence. Based on present needs for the APS Upgrade, twelve 160kW SS rf amplifier systems will be...
The SPS injection kicker system comprises twelve MKP-S (small aperture) modules and four MKP-L (large aperture) modules. An upgraded MKP-L magnet was installed in the SPS, during December 2022, in view of the higher beam intensity needed in the future for High-Luminosity-LHC. The upgrades have significantly reduced the beam coupling impedance and consequent beam induced heating. The improved...
In this study, we present a deep learning-based pipeline for predicting superconducting radio-frequency (SRF) cavity faults in the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab. We leverage pre-fault RF signals from C100-type cavities and employ deep learning to predict faults in advance of their onset. We train a binary classifier model to distinguish between stable...
During the operation of the Continuous Electron Beam Accelerator Facility (CEBAF), one or more unstable superconducting radio-frequency (SRF) cavities often cause beam loss trips while the unstable cavities themselves do not necessarily trip off. The present RF controls for the legacy cavities report at only 1 Hz, which is too slow to detect fast transient instabilities during these trip...
Coherent electron Cooling (CeC) experiment aims on demonstrating cooling if 26.5 GeV/u ion beam circulating in RHIC. We will present results of the CeC experiment with special focus won the use and the control of the broad-band micro-bunching Plasma Cascade Amplifier with bandwidth of 15 THz. We will also discuss connection of this experiment with the developing the CeC cooler for future
NanoTerasu is a new 3 GeV compact soft X-ray (SX) light source having a circumference of 349 m constructed in Japan. The lattice structure is a type of multi-bend achromat with design emittance values of 1.14 nm·rad and 10 pm·rad, respectively. A target stored current is set to 400 mA to provide a high coherence and highly brilliant light from extreme ultraviolet to SX range. The injector...
MedAustron is a synchrotron-based cancer therapy center located in Lower Austria. Patients are treated with proton and carbon ion beams in an energy range of 62-252 MeV/u and of 120-400 MeV/u respectively. The facility features three clinical irradiation rooms, among which horizontal and vertical beam lines as well as a proton gantry are available for treatment. A fourth irradiation room (IR1)...
The LBNL Advanced Light Source, a pioneering third-generation soft x-ray synchrotron radiation source operating at 1.89 GeV with a 2~nm beam emittance, stands as one of the earliest facilities in its class, continually evolving to maintain its status at the forefront of soft x-ray sources. This paper reviews the most significant advancements in the accelerator's hardware and software...
The Advanced Photon Source Upgrade (APS-U) project has developed and installed a multi-bend achromat (MBA) lattice operating at 6.0 GeV beam energy to replace the existing APS storage ring lattice that operated at 7.0 GeV. A major part of the project is to install 60 hybrid permanent magnet undulator (HPMU) insertion devices (IDs) that include 12 revolver undulators, each with two magnetic...
The stress-strain state of the titanium foils of the accelerator output windows at various thicknesses was studied with the choice of first-grade titanium foil as a brand. The latter is more affordable and accessible compared to a second-grade titanium foil. The deformation diagram, density, Young's modulus, and Poisson's ratio of the first-grade titanium were selected as initial data....
To reduce filling times and enable advanced injection schemes, it is desirable for the Diamond-II booster to provide high charge in both single and multi-bunch modes. The single bunch charge will be limited by short range wakefields in the booster, and long-range wakefields limit the charge for the multi-bunch trains. Due to the relatively low 100 MeV injection energy into the booster, the...
CW magnetrons designed and optimized for industrial heaters, driven by an injection-locking signal, were suggested to power Superconducting RF (SRF) cavities. However, CW magnetrons are regenerative devices that apply some of their output back to its input to add to the input signal, increasing the gain/amplification. to avoid large regenerative instability in operation, we propose a new...
In pursuit of maximizing the performance of the Taiwan Photon Source (TPS), we conducted a feasibility study aimed at reassessing and optimizing the lattice configuration within the existing tunnel infrastructure. One of our main objective is to minimize displacement of source points for insertion devices (IDs) while augmenting overall beam performance. To achieve this, we propose an upgraded...
The Electron Ion Collider (EIC) Hadron Storage Ring (HSR) will accelerate all species except protons through transition to the desired storage energy. The effects at transition may cause unwanted emittance blowup beam loss due to bunch area mismatch and negative mass instability. In this paper, we will show the longitudinal dynamics of transition crossing in the HSR with current parameters...
The Korea fourth-generation storage ring (Korea-4GSR) project was launched in 2021 to generate high-brightness photon beams as a diffraction-limited light source. The 200 MeV beam is injected into the booster synchrotron. The beam parameters and transmission efficiency fluctuate with initial beam conditions such as beam Twiss parameters and centroid offsets during the injection and energy...
Stuctural Health Monitoring (SHM) program at European Spallation Source (ESS) aims to perform preventive studies on machine structure through the development and implementation of non-destructive techniques. The goal of this program is to: 1. Understand cavity material-ion beam interaction mechanisms 2. Quantify material damage at nominal operational parameters and abnormal scenarios, 3. Study...
Ultra-intense, ultra-fast, near-infrared (NIR) solid-state lasers based on chirped pulse amplification (CPA) are main radiation sources to support strong-field scientific research. At the same time, the wavelength scaling of fundamental physical processes calls for extending the spectral coverage into the long-wave infrared (LWIR) domain (8–14 µm). Using optical transitions between vibrational...
As Thomas Jefferson National Accelerator Facility (Jefferson Lab) looks toward the future, we are considering expanding our energy reach by using Fixed-Field Alternating Gradient (FFA) technology. Significant efforts have been made to design a hybrid accelerator which combines conventional recirculating electron LINAC design with permanent magnet-based FFA technology to increase the number of...
A collaboration agreement between the ALBA, DESY and HZB institutions was signed on 2021 in order to commission the 3rd harmonic normal conducting, HOM damped, active cavity designed and prototyped by ALBA. The cavity prototype arrived to ALBA in December 2021, and successfully passed the low power RF and vacuum tests. Afterwards, in January 2022 it was sent to HZB and mounted in the...
The SIS100 accelerator, currently under construction in Darmstadt (Germany), consists of six arc and straight sections. Each of the six cryogenic arc sections comprises fourteen regularly repeating optical cells (lattice). Each standard cell includes two dipole magnets and two quadrupole units integrated in a quadrupole doublet module. The SIS100 String Test technically represents one standard...
In advanced light sources such as 4th generation synchrotrons and Free Electron Lasers (FELs), undulators are important devices to produce photons with high brilliance. This necessitates to reach highest possible magnetic fields. For a given magnetic gap and period length this demand can only be accomplished by using the superconducting undulator (SCU) technology.
At the Institute for Beam...
Previous TDR (Technical Design Report) studies for the SOLEIL upgrade project (SOLEIL II) have converged towards a lattice alternating 7BA and 4BA HOA (High Order Achromat) type cells providing an ultra low natural horizontal emittance value in the 85 pm·rad range at an energy of 2.75 GeV. The new TDR lattice is an evolution that keep the insertion devices photon source points at their present...
Brookhaven National Laboratory (BNL) was recently chosen to host the Electron Ion Collider (EIC), which will collide high energy and highly polarized hadron and electron beams with a center of mass energy up to 140 GeV and a luminosity of up to 1e+34 1/cm^2/s. Part of the accelerator complex is a Rapid Cycling Synchrotron (RCS), which is planned to accelerate electrons from 400 MeV to 18...
The correction of storage ring magnetic errors typically requires the use of multiple programs. However, there are generally differences in the correction results between different programs. We may perform error correction in one program and then continue with other tasks in another program, which requires us to accurately achieve the conversion of the lattice between different programs after...
The Data Platform is a fully independent system for management and retrieval of heterogeneous, time-series data required for machine learning and general data science applications deployed at large particle accelerator facilities. It is an independent subsystem within the larger Machine Learning Data Platform (MLDP) which provides full-stack support for such facilities and applications [1]....
The accelerator of CSNS is composed by a 80 MeV H- linac and a RCS ring. The H- beam from the linac is stripped and injected to RCS where the stripped proton beam will be accumulated and boosted to 1.6 GeV. In order to improve the injection efficiency, it is a must to know and control the linac beam parameters. In this paper, the energy spread of H- beam at the LRBT of CSNS linac is measured.
We present the design and experiment of a laser system for the very compact inverse Compton scattering (ICS) γ-ray source (VIGAS). The laser system comprises a photo injector drive laser and a scattering laser system. The photocathode drive laser system produces ultraviolet (UV) pulses with 575 μJ energy, 9.4 ps FWHM pulse width, and 10 Hz repetition at 267 nm central wavelength, which...
The SAPS is a fourth-generation light source which is planned to be built at the Guangdong Province, the south of China. On injection option for the SAPS is a booster ring with a low energy linac. The linac initially provides full charge bunches to booster and then the boosted beams are injected to the storage ring via swap-out injection. When the brightness of the storage ring become lower,...
As part of the Electron-Ion Collide (EIC) upgrade at Brookhaven National Laboratory (BNL), the development of new beam screens for the vacuum system is underway. The mechanical design of the beam screens received support from CERN, particularly in addressing the mechanical response during a magnet quench, i.e. a resistive transitions in the superconducting magnets. Maintaining an overall...
The Mainz Energy recovering Superconducting Accelerator MESA is a multi-turn energy recovery linac with beam energies in the 100 MeV regime currently under construction at Institut für Kernphysik (KPH) of Johannes Gutenberg-Universität Mainz. The main accelerator consists of two superconducting Rossendorf type modules, while the injector MAMBO (MilliAMpere BOoster) relies on normal conducting...
The undulator is the core device for producing high energy synchrotron radiation light in Synchrotron Radiation and Free Electron Laser facilities. The long-term operation of the undulator is bound to be damaged by radiation. Furthermore, this radiation damage leads to the reduction or even demagnetization of the magnetic field, directly affecting the electron beam's operating state and the...
The PSI Positron Production experiment, known as P\textsuperscript{3} or \textit{P-cubed}, is a proof-of-principle positron source and capture system that can greatly improve the state-of-the-art positron yield. The P\textsuperscript{3} project is led by the Paul Scherrer Institute in Switzerland, and addresses the long-standing challenge faced by conventional injector facilities to generate,...
Reinforcement Learning (RL) is a unique learning paradigm that is particularly well-suited to tackle complex control tasks, can deal with delayed consequences, and can learn from experience without an explicit model of the dynamics of the problem. These properties make RL methods extremely promising for applications in particle accelerators, where the dynamically evolving conditions of both...
The X-ray beam position monitors (XBPMs) installed in the front end system of the Taiwan Photon Source (TPS) is discussed in this article. This XBPM has an Advanced Photon Source (APS) blade type. Calibration has been finished for most XBPMs in the front end of the insertion device beamline. The stability and resolution of the XBPMs will be introduced in the article. The problems encountered...
The European LEAPS-INNOV project has launched a Research and Development program dedicated to the design of a new generation of germanium detectors for X-ray spectroscopy applications. The present article shows the results of the thermomechanical simulations of this design, based on finite element analysis (FEA) studies, under vacuum and cryogenic conditions. The first results of these...
Our focus centers on numerical investigation into the transient response of optics when subjected to instantaneous heat deposition. The heat load deposited onto crystal optics, coupled with the emission of strain waves, has the potential to induce crystal deformation and vibrations. These phenomena carry detrimental consequences for optic performance, particularly in terms of wavefront...
A central part of CERN’s Future Circular collider study (FCC) is a ~91 km circumference lepton collider and its injector complex. This contribution outlines the various kicker systems needed to transport the lepton beams from the electron source up to the collider dump system. The individual system requirements are presented, and the choice of design parameters and technology options for both,...
This paper addresses the automation of particle accelerator control through reinforcement learning (RL). It highlights the potential to increase reliable performance, especially in light of new diagnostic tools and the increasingly complex variable schedules of specific accelerators. We focus on the physics simulation of the AWAKE electron line, an ideal platform for performing in-depth...
The bending, quadrupole, and sextupole power supplies in the J-PARC Main Ring (MR) have been upgraded ramping up the average beam power for fast extraction (FX) operation for the neutrino oscillation experiment and slow extraction (SX) operation for the experiments in the hadron facility. The repetition cycles have been shortened from 2.48 sec. to 1.36 sec. for the FX operation and will be...
Conceptual studies for a muon collider identify fast-ramping magnets as a major design challenge. Rise rates of more than 1 T/ms are attainable with normal-conducting magnets, incorporating iron yokes to make sure that stored magnetic energies and inductances stay below reasonable thresholds. Moreover, for energy efficiency, the magnets need to exchange energy with capacitors, such that the...
For achieving sufficient RF power from a solid state amplifier for accelerate particles applications usually many transistor stages need to be combined. Power levels of more than one kilowatt (kW) per transistor are state of the art for a variety of frequencies. Depending on the required total output power for multi ten kW systems a combining structure is needed. The approach of a sequential...
In ultrafast electron diffraction experiments, the electron beam's length is crucial as it determines the timescale for observing ultrafast dynamic changes. Therefore, achieving continuous control over the length of these beams within a specific range is paramount for broadening the research scope in ultrafast science. This regulation ensures the accuracy of diffraction images from diverse...
The Los Alamos Neutron Science Center (LANSCE) is one of the oldest operating accelerators in the United States, having recently celebrated its 50th anniversary of operation. LANSCE is comprised of an 800-MeV linac capable of concurrently accelerating both H+ and H- ions, and can presently provide beam to six separate user stations.
We present an overview of proposed and underway upgrade and...
The Los Alamos Neutron Science Center (LANSCE) is one of the oldest operating high-power accelerators in the United States, having recently celebrated its 50th anniversary of operation. LANSCE is comprised of an 800-MeV linac capable of concurrently accelerating both H+ and H- ions, and can presently provide beam to six separate user stations.
The Area A end-station at LANSCE is the site of...
The current Booster Main Magnet Power Supply (MMPS) has a maximum power draw of 18 MW drawn directly from the AC power line. To support this high power draw, the Booster has a dedicated 69 kV substation. The Rapid Cycling Synchrotron for the Electron Ion Collider will also require a 69 kV substation. To free the existing 69 kV substation, the Booster MMPS will be upgraded to a capacitor style...
Several accelerator facilities serving critical need of the US scientific mission are planned for the next decades. The Electron Ion Collider (EIC) is one of them and it will be the only new collider to be built in the near future. The EIC is a unique, high-energy, high-luminosity, polarized beam collider that will be one of the most challenging and exciting accelerator complexes ever built....
A new accelerator facility (FAIR) is currently being built at GSI Helmholtz Centre for Heavy Ion Research in Darmstadt, Germany. The FAIR accelerator facility will consist of various beam lines, which provide different functions and experiments using various particle beams (ions, proton and anti-protons). Due to unprecedented circumstances, the FAIR project is currently divided into several...
The strength of a first-order spin-orbit resonance is defined as the amplitude of the corresponding Fourier component of the spin-precession vector. However, it is possible to obtain the resonance strength without computing the Fourier integral directly. If a resonance is sufficiently strong, then to a good approximation, one can neglect all other depolarizing effects when near the resonance....
With the present proton electric dipole moment (pEDM) storage ring design [1], the counter rotating (CR) beam closed orbits will separate vertically if there is a nonzero radial magnetic field Bx. If a quadrupole electric field Ey is also present, then its direction would be opposite for the CR beams hence it becomes a potential source for a false EDM signal. In this work, we model this...
The paper focuses on calculating the longitudinal and transverse wake-fields and impedances of the FCC-ee collimators through electromagnetic simulations using CST, ECHO3D and IW2D codes. The conducted studies have revealed that the collimation system can significantly contribute to the overall collider impedance/wake budget, both broad-band and narrow-band. The single bunch dynamics...
A superconducting radio frequency (SRF) cryomodule (CM) for the International Linear Collider (ILC) Technology Network (ITN) is being developed at KEK. In the scope of this, a waveguide system is being designed. Its main features are a low center of gravity, a reduced number of corners and waveguide elements, and a compact bellow for connecting it to the input power coupler. Furthermore, the...
The timing system is a critical element in scientific facilities such as particle accelerators or laser ignition installations. The different subsystems that integrate these scientific facilities need to have a common notion of time. This common time reference is provided by the timing system. Thanks to that, it is possible to operate the machine in a time coherent manner and to properly track...
Free electron lasers (FEL) have made significant progress in the last decade, offering unique opportunities of high brightness radiation to the users’ community. Various advanced schemes aiming at achieving fully coherent, stable X-ray pulses are proposed and are actively being investigated and developed. Self-amplified spontaneous emission (SASE) can be used to generate intense coherent...
Various initiatives in Europe have been launched to study superconducting magnets for a rotatable gantry suitable to deliver up to 430 MeV/u carbon ions for hadron therapy. Different technologies and layouts are being considered: the baseline solution is developed within the EuroSIG collaboration and consists of a strongly curved cos-$\theta$ dipole based on the classical NbTi superconductor....
In the context of research on simultaneous heavy ion radiotherapy and radiography, a mixed carbon/helium ion beam has been successfully established and investigated at GSI for the first time to serve fundamental experiments on this new mode of image guidance. A beam with an adjustable ratio of 12C3+/4He+ was provided by the 14.5 GHz Caprice ECR ion source for subsequent acceleration in the...
PAL-XFEL has achieved successful operation with both SASE and self-seeding modes. In an effort to broaden the capabilities of PAL-XFEL, research has been conducted on the generation of two-color XFEL pulses, leading to the development of two additional modes: two-color XFEL with time delay and pulse duration control, and time-synchronized two-color XFEL. In the first mode, a dipole magnet at...
Orbital angular momentum (OAM) photon beams are excellent tools for non-contact optical manipulation of matter in a broad photon energy range. A free-electron laser (FEL) oscillator is well-suited for studying OAM beams with various features including a wide spectral coverage, wavelength tunability, two-color lasing, etc. Here, we report the first experimental demonstration of superposed OAM...
We will describe spin-transparent storage rings that exhibit spin-coherence times of several hours and store a large number of particles and their use in novel applications. For example, these rings can be used to directly measure the electric dipole moment of the electron, relevant to CP violation and matter-antimatter asymmetry in the universe, and to search for dark energy and ultra-light...
The FERMI free-electron laser (FEL) facility has recently achieved a significant milestone with the successful implementation of the echo-enabled harmonic generation (EEHG) scheme in the FEL-1 amplifier line. This advancement is part of a broader upgrade strategy aiming at expanding the covered spectral range of the facility to the entire water window and beyond. Through this upgrade, the...
SLAC developed ACE3P is a parallel multi-physics electromagnetics (EM) simulation toolkit aiming for virtual prototyping of accelerator and RF component design, optimization and analysis. In this paper, we will present the latest progress on ACE3P modeling capabilities. First, for the time domain solver T3P, modeling of nonlinear materials with higher-order electric susceptibilities has been...
Transverse deflection structures (TDS) are used as diagnostic tools for linac-based accelerators. Since their reintroduction in the early 2000s, their development has been continued in several laboratories, in particular to improve temporal resolution given the ongoing tendency of getting shorter and shorter electron bunches. Furthermore, the development of a new TDS with variable streaking...
The Main Ring (MR) at J-PARC (Japan Proton Accelerator Research Complex) is a proton synchrotron that accelerates protons from 3 GeV to 30 GeV. One of the two MR's extraction modes is slow extraction using third-order resonance toward the Hadron Experimental Facility, where various particle and nuclear physics experiments are conducted. There are two major points in the slow extraction: beam...
We present the results of the first experiments on 6-dimensional phase-space tracking of a single electron in a storage ring, using a linear multi-anode photomultiplier tube for simultaneously measuring transverse coordinates and arrival times of synchrotron-radiation pulses. This technology makes it possible to fully reconstruct turn-by-turn positions and momentums in all three planes for a...
The institute of rare isotope science (IRIS) developed a superconducting linac facility (called RAON, Rare isotope Accelerator complex for ON-line experiments) through the rare isotope science project (RISP). The superconducting linac (SCL) consists of two different type of cavities, QWR and HWR. It is designed to accelerate a variety of ions, from protons to uranium. Uranium beams can be...
The Extended Electron Beam Ion Source (EEBIS) was installed and commissioned for the Relativistic Heavy Ion Collider (RHIC), NASA Space Radiation Laboratory (NSRL), and future Electron Ion Collider (EIC) at Brookhaven National Laboratory (BNL). Within one month of completed installation, daily operation of multiple ion beams for Galactic Cosmic Ray (GCR) simulation for NSRL science was...
LCLS-II commissioning is well under way. As an indirect diagnostic, electron beam-induced higher order mode (HOM) signals from the RF cavities in the first LCLS-II cryomodule are routed outside the accelerator and filtered to select dipole modes. The signals are amplified and detected using a Schottky diode, following a design tested at Fermilab. The detected signal magnitude is proportional...
The Future Circular Electron-Positron Collider (FCC-ee) is CERN's leading proposal for the next generation of energy-frontier particle accelerators. To reach integrated luminosity goals, it aims to be operational for minimum 80 % of the scheduled 185 physics days each year. For comparison, the Large Hadron Collider (LHC) achieved 77 % in 2016-2018. There are additional challenges in the FCC-ee...
New technical approaches are under investigation to further push the intensity frontier of the next generation heavy ion synchrotrons. Residual gas dynamics and corresponding charge exchange processes are key issues which need to be overcome by means of advanced UHV system technologies, but also by a focused design of the synchrotron as a whole. Cryogenics and superconductivity enable high...
An update on SuperKEKB status will be presented including an overview of performance limitations and experience with nonlinear collimation.
Taiwan heavily relies on imported fuel for power generation, making the country susceptible to energy market risks. To mitigate this issue, the government is actively promoting the adoption of renewable energy sources, such as solar and wind power, while also encouraging companies to enhance their energy-saving efforts. At NSRRC, five major energy-saving practices were implemented, including...
The secondary emission of electrons and their interaction with the electromagnetic fields of charged particle beams can lead to the build-up of electron clouds in accelerator beam chambers. The interaction of the electrons with both the beam and the chamber walls leads to detrimental effects, such as transverse instabilities and emittance growth, beam loss, pressure rise and heat load. Such...
This talk will outline the challenges ahead in high power targetry and the material R&D plan for achieving 2.4 MW and beyond, windows and targets.
CERN is contemplating further advancements in the energy frontier through the Future Circular Collider (FCC) study, envisioning a 90.7 km underground accelerator with multiple energy stages over time. Following the European Strategy for Particle Physics recommendation in 2020, CERN initiated a feasibility study to scrutinize all aspects of the FCC project.
A crucial component of this study...
A pulsed muon beam has been generated by a 3-GeV 333-microA proton beam on a muon target made of graphite at J-PARC, Materials and Life Science Experimental Facility. The first muon beam was successfully generated in 2008, and 300-kW proton beam has been operated by a fixed target till 2014. To extend the lifetime, a muon rotating target, in which the radiation damage is distributed to a wider...
The design and study of the Circular Electron Positron Collider (CEPC) present a significant challenge, requiring the proper modeling of various physical phenomena such as the crab-waist collision scheme with a large Piwinski angle, strong nonlinear effects, energy sawtooth, beam-beam interactions, and machine impedances. In response to this challenge, the APES software project was proposed in...
As beam power continues to increase in next-generation accelerator facilities, high-power target systems face crucial challenges. Components like beam windows and particle-production targets must endure significantly higher levels of particle fluence. The primary beam’s energy deposition causes rapid heating (thermal shock) and induces microstructural changes (radiation damage) within the...
ESS is completing the installation of the first phase of operation, which will start in fall 2024 on the partial beam dump and proceed with operation on the target in 2025, after receiving the intentional neutron production license from the authorities. All modules for this operation phase, with an energy reach of 870 MeV and a power capability of 2 MW, will be tested by spring 2024. The CM...
A multi-TeV muon collider has the unique potential to provide both precision measurements and the highest energy reach in one machine that cannot be paralleled by any currently available technology. There has been significant physics interest on Muon Colliders recently as indicated by the number of publications, relevant workshops, Snowmass activities but also the P5 report. This study...
Particle tracking serves as a computational technique for determining the mean field of dynamically tracked charged macroparticles of a particle beam within an accelerator. Conventional solver tend to neglect collisionality, resulting in loss of relevant information (particle and momentum redistribution). In this study, macro-particle collisions are incorporated into a 3D Poisson solver. In...
Powered optics magnets which could be stacked in a very dense alternating pattern could enable a higher density of focusing in beamlines, with potential use for e.g. muon beams or high-current hadron beams at low energy. Here, we investigate such a design of quadrupole, where the yoke is energised by straight conductors running parallel to the beam, and does not require conductor to pass...
The LANSCE H- Ion Source utilizes a cesium coated converter to induce H- surface conversion. To achieve an optimal cesium coating, a heated cesium reservoir and transfer tube vaporizes cesium onto the converter surface. An initial coating of cesium is done via an initial cesium transfer. During this process, the cesium heater is brought to a high initial temperature (250°C) and is slowly...
The High-Energy Physics community has established that a multi-TeV Muon Collider should be included in plans for future high energy facilities. We consider the possibility of siting the future high energy muon collider at Fermilab. Using magnet and RF system capabilities that are expected to be readily available in the near future a complete muon collider facility with up to ~10 TeV center...
There is increasing interest in developing accelerator technologies for space missions, particularly for fundamental science. In order to meet these mission needs, key accelerator technologies must be redesigned to be able to function more reliably and efficiently in a remote and harsh environment. In this work we focus on a modest electron injector system, specifically the traditional...
The ISIS-II Neutron and Muon source is the proposed next generation of, and successor to, the ISIS Neutron and Muon Source based at the Rutherford Appleton Laboratory in the United Kingdom. Anticipated to start construction in 2031, the ISIS-II project presents a unique opportunity to incorporate environmental sustainability practices from its inception.
A Life Cycle Assessment (LCA) will...
SSRF (Shanghai Synchrotron Radiation Facili-ty)/SXFEL (Shanghai Soft X-ray FEL) Facility has de-veloped an advanced variable polarization transverse deflecting structure TTDS (two-mode transverse deflect-ing structure) to perform variable polarization based on the design of a dual-mode RF structure. The 15-cell prototype of the TTDS was fabricated at SSRF/SXFEL. Because the two modes operate...
The simultaneous optimization of multiple objective functions is needed in many particle accelerator applications. In this paper, we report on the development of an open source parallel evolution based multi-objective optimization package that uses a variable population from generation to generation and an external storage to save good solutions. Two heuristic optimization methods, one uses...
Beam Delivery Simulation (BDSIM) is a Monte Carlo particle tracking simulation tool for modelling energy deposition in 3D models of particle accelerators. Initially conceived in 2001 to model the collimation system in the International Linear Collider (ILC), in recent years BDSIM has undergone a significant transformation across virtually its entire code base. As a result of its newer...
After current upgrades are completed, the Compact Linear Accelerator for Research Applications (CLARA) at Daresbury Laboratory (UK) will be capable of producing femtosecond-scale electron bunches, which will be used in the full energy beam exploitation (FEBE) experimental area. CLARA will employ multiple techniques to manipulate the longitudinal beam profile, including a variable bunch...
In 2023, a significant reconfiguration has been undertaken on the first radiographic axis AIRIX to assure its synchronization with the second LINAC of EPURE facility. On AIRIX, the high current functioning point in progress since 2016 (2.6 kA / 19.2 MeV) has been maintained. A number of experimental tests has been performed to further understand the BBU beam instability phenomenon, mainly in...
During the last years of operation of the COSY facility, significant improvements were made in beam control and diagnostics. Many systems have been upgraded from a Tcl/Tk based control system to EPICS. One of the advantages of EPICS is the coherent communication via Process Variables (PVs). This allowed us not only to control the synchrotron and its injection beam line (IBL) through GUIs but...
Achieving the low emittances necessary for a muon collider requires ionization cooling. Much of that cooling occurs in compact cooling cells where superconducting coils and conventional RF cavities are closely interleaved [1]. The real challenges for these cooling cells reside in their engineering challenges: high field solenoids, RF cavities, and absorbers, often designed near technological...
The Cornell Electron Storage Ring (CESR) beam position monitors (BPM) consists of four button-shaped pick-up electrodes, each individually instrumented with readout electronics that allow acquisition of turn-by-turn data. The beam position is reconstructed using the measured signal amplitude from the four electrodes. Systematic effects such as physical differences between the electrodes...
IRIS (Innovative Research Infrastructure on applied Superconductivity) is a major project to build a research infrastructure in applied superconductivity, recently approved in Italy and led by INFN Milano. In this framework, we are developing two superconducting energy savings devices, both working at 20 K either in helium gas flow or by cold-heads: An HTS dipole (Energy Saving Superconducting...
Properties such as high quantum efficiency (QE), low thermal emittance, and longevity are crucial features for the rapidly developing electron accelorators. Compared to the traditional sequential deposition, the co-evaporation method is reported to yield better surface roughness, film crystallinity, and high quantum efficiency for photocath-ode materials. Here we present the effort in...
Maintaining beam-accelerating structure RF phasing of a linac is crucial for maintaining optimal beam transport performance. At the Advanced Photon Soure (APS), in 2008 we implemented an analog phase detector system using the Analog Devices AD8302 phase detector chip. The APS phase detectors use as an S-Band RF phase reference an out-coupled signal from the waveguide supplying the accelerating...
MeV ultrafast electron diffraction has become a new frontier for the study of molecular dynamics. With the temporal resolution of MeV-UED being limited by the electron bunch length at the target, electron sources used for this technique are becoming ever more intricate in the the push for shorter bunches length. However, moving to these complex setups makes them less feasible in a small-scale...
Currently, radiofrequency (RF) power to the Argonne Advanced Photon Source (APS) storage ring and Booster cavities is provided by several klystrons. APS is in the process of replacing the storage ring klystrons with clusters of 160 kW solid state amplifier (SSA) gradually. It is required to keep most of the existing equipment racks, klystrons and cable trays for smooth operation and transition...
To realize very precise measurement of the muon spin precession frequency in the level of sub-ppm, a muon beam is injected into a precisely adjusted storage magnet of sub-ppm uniformity via “Three-dimensional spiral beam injection scheme [1]” at J-PARC muon g-2/EDM experiment. This injection scheme requires a strongly X-Y coupled beam which is applied by eight rotating quadrupoles on the 10m...
The Korean 4GSR project is currently under construction in Ochang, South Korea, with the aim of first beam commissioning in 2027. Designed to achieve an emittance approximately 100 times smaller than that of third-generation synchrotron radiation storage rings, the project requires the development of several high-precision beam diagnostic devices. In particular, the beam position monitor is...
We are developing a compact synchrotron light source using laser electron acceleration, focusing on creating a tabletop accelerator-based radiation system. Our approach involves a small ring-type dipole with block-shaped permanent magnets, prioritizing cost and weight reduction. Simple beam dynamic calculations revealed that a smaller electron beam divergence angle results in a more stable...
The storage ring from the SLS is currently in the process of a significant upgrade to a new multi-bend achromat that aims to improve the performance of the machine by allowing it to deliver even brighter beams to the beamlines. The linear accelerator of the SLS is an ageing piece of infrastructure that needs to continue to run for the few decades to continue to feed SLS 2.0 reliably. In this...
A digital direct RF feedback (DDRF) has been implemented in the DLLRF of the ALBA synchrotron light source in order to mitigate the beam loading effects of the beam. Specifically, with the DDRF implemented in the main cavities, the tune shift due to beam loading can be minimized and therefore the DC-Robinson instability can be mitigated. It can also be used to minimize voltage drops in case of...
Advanced Photon Source Upgrade (APS-U) storage ring, currently in installation and testing, is set for beam commissioning in early 2024. In the APS-U storage ring, there are 560 Beam Position Monitor (BPM) pickups, each equipped with high resolution electronics. This paper presents outcomes from pre-beam testing and beam commissioning of the APS-U BPM system. We discuss tailored features for...
A beam position monitor based on Cherenkov diffraction radiation (ChDR) is being investigated as a way to disentangle the signals generated by the electromagnetic fields of a short-pulse electron bunch from a long proton bunch co-propagating in the AWAKE plasma acceleration experiment at CERN. These ChDR BPMs have undergone renewed testing under a variety of beam conditions with proton and...
Beam tomography is a method to reconstruct the higher dimensional beam from its lower dimensional projections. Previous methods to reconstruct the beam required large computer memory for high resolution; others needed differential simulations, and others did not consider beam elements' coupling. This work develops a direct 4D reconstruction algorithm using Markov Chain Monte Carlo.
The determination of equilibrium emittance stands as a critical factor in optimizing the luminosity of the Future Circular Collider (FCC). In order to have accurate simulations and understanding of the emittance, multiple effects have to be taken into consideration including errors in the machine, solenoid effects, synchrotron radiation and beam-beam effects. The novel X-Suite software aims to...
Bmad-Julia is a new, open-source software project for modern accelerator simulations with an emphasis on Machine Learning. As compared to existing accelerator codes, reverse differentiability, e.g. for the optimization of neural networks, will be embedded. Multiple standalone Julia packages are being developed that provide fundamental tools and methods commonly needed in accelerator...
Most particle accelerators utilize beams with a charge density concentrated in the center of the bunch in real 3-dimensional space and the 6-dimensional phase space. In this work, by enhancing the space-charge forces in the photo-cathode injector of the Compact Linear Electron Accelerator for Research (CLEAR) at CERN, we produce electron bunches with a “bubble-like” shape, with a charge...
The linear acceleration part of the SHINE project consists of two 3rd harmonic cryogenic modules which are operating at 3.9 GHz. Each of the cryomodules consists of eight 3.9 GHz 9-cell superconducting cavities. The SHINE specifications of the 3.9 GHz cavities are Qo >2.0e+9@13.1 MV/m and maximum accelerating gradient >15 MV/m. The 3.9 GHz cavities were treated with buffered chemical polishing...
Linacs are an integral part of high-gradient accelerating structures for X-ray Free Electron Laser (XFEL) facilities. For high energy (42+ keV) x-rays, this translates into a longer linac (linear accelerator), which in turn translates into increased cost due to the larger footprint. One such case is the DMMSC (Dynamic Mesoscale Material Science Capability) at Los Alamos National Laboratory....
The SC Linac of SHINE (Shanghai HIgh repetition rate XFEL aNd Extreme light facility) comprises 79 cryomodules housing 609 1.3 GHz TESLA type superconducting cavities (SCCs), and 16 3.9 GHz SCCs. These SCCs and cryomodules should be tested in ATH (cryomodule Assembly and Test Hall) at SSRF (Shanghai Synchrotron Radiation Facility) campus. Four VTFs (SCC Vertical Test Facility) and four HTFs...
CERN is pursuing several initiatives to reduce its impact on the environment through an integrated approach to address all the objectives set by the relevant United Nations (UN) Sustainable Development Goals (SDG). In particular CERN is committed to respect the net-zero paradigm for future machines and has established a Sustainable Accelerators Panel to harmonize the approach to sustainability...
We performed an optimisation study of a C-band photoinjector for high-charge electron beams. Such a device is capable of producing high brightness electron beams, with low energy spread and small transverse emittance, which are properties required by Inverse Compton Scattering radiation sources and compact light sources in general. This work aimed to carry out, via numerical simulations,...
At the Karlsruhe Research Accelerator (KARA) facility, an electron beam is generated by a thermionic electron gun, pre-accelerated to 53 MeV by a microtron and then ramped up to 500 MeV in a booster synchrotron before being injected into the storage ring, where a final electron energy of 2.5 GeV is reached. Compared to a 2D camera, when using 1D photodetectors either directly at the...
CLARA is a 250 MeV electron facility at Daresbury Laboratory, which will provide short bunches between 1 and 250 pC for a variety of experiments, including novel acceleration experiments. As part of the Phase 2 upgrade new charge measurement systems have been installed. This paper presents the charge measurement systems that will be used on CLARA, as well as commissioning results without beam...
The storage ring of the SOLEIL II project will be based on a low-emittance multi-bend achromat 7BA-4BA lattice resulting in very compact lattice (1500 magnets for a 354 m long ring), very high quadrupole gradient (120 T/m), strong sextupole (8000 T/m2), and moderate octupole (50 000 T/m3) with a beam circulating in a tiny vacuum chamber of 12 mm diameter. The project makes extensive use of...
In Mithra Laboratory at UCLA, we are commissioning an S-band Hybrid gun which has a photocathode RF gun and a traveling-wave velocity buncher section contained in one integrated structure. To analyze its performance, we have measured the beam energy at various launch phases and the cavity temperatures. The beam charge was observed up to 200 pC, and emittance and bunch length measurements are...
A Compact Transverse Deflecting System (Compact-TDS) designed for longitudinal electron bunch diagnostics in the femtosecond regime is presently undergoing commissioning at the Karlsruhe Institute of Technology (KIT). This technique, based on THz streaking using a resonator structure, demands a high level of electron beam controllability and stability at the micrometer scale. To meet these...
Hefei advanced light facility (HALF) is a fourth-generation light source under construction. Its storage ring is a diffraction-limited one with an energy of 2.2 GeV and an extremely low emittance of less than 100 pm·rad. The real storage ring is different from the ideal lattice due to various kinds of errors. Those errors come from many sources, like misalignment of components, imperfect...
As part of the Snowmass'21 planning exercise, the Advanced Accelerator Concepts community proposed developing multi-TeV linear colliders and considered beam-beam effects for these machines [1]. Such colliders operate under a high disruption regime with an enormous number of electron-positron pairs produced from QED effects. Thus, it requires a self-consistent treatment of the fields produced...
Most superconducting thin films found on SRF cavity are generally produced through magnetron sputtering using niobium (Nb) as target. Yet, this technique can still be improved as the resulting film lack in efficiency. Alternative materials such as NbTiN could potentially be used with significant improvement compared to pure Nb films.
Here, we report the use of both high-power impulse...
Ultrafast electron diffraction and microscopy (UED/UEM) has advanced beyond proof-of-concept stage into the realm of instrumentation. To date, most UED/UEMs have been constructed around high-gradient RF-driven electron guns designed as X-FEL beam sources.
A UED/UEM system driven by a CW beam, either normal- or superconducting, offers several potential performance benefits over high-gradient...
The cooling section of the Muon Collider requires a number of solenoidal coils of various diameters (0.05-2 m) and fields (2-60 T). An unusual feature of the cooling section is that the RF cavities operates under the large magnetic fields and field gradients generated by the focusing elements. Here we present the design of a test facility based on split coils, wound with HTS, to study the...
20 T dipole magnets are being considered for the next generation of particle accelerators. The nominal operation field of 20 T is above the practical limit of Nb3Sn accelerator magnets and, thus, it requires using superconductors with higher critical parameters such as High Temperature Superconductors (HTS). The high cost of HTS and the more complicated technology of HTS coils makes attractive...
The Muon Cooling Complex is a crucial component of the future high-energy Muon Collider, where the ionization cooling technique is employed to reduce muon beam emittance by several orders of magnitude. This cooling technique necessitates the utilization of normal conducting, RF-accelerating cavities operating within a multi-Tesla magnetic field. This study illustrates the conceptual RF design...
We study the effects of high voltage DC bias on the fundamental power couplers of the ESS elliptical SRF cavities. These tests were carried out at the TS2 facility, where cryomodule acceptance and characterization tests are carried out. We present the observed effects of positive and negative bias field on multipacting in the RF couplers, as well as the implications for operation in the ESS linac.
SHINE project requires about 75 cryomodules with superconducting radio-frequency cavities to accelerate the beam to 8 GeV. Key components, technologies of cryomodule have been developing through prototypes and pre-series cryomodules. Up to now, several sets of cryomodule with high-Q cavities have been assembled and tested. We present the development status of SHINE cryomodules, including...
The Inverse Compton Scattering Interaction Point (ICS-IP) vacuum chamber provides a UHV environment where the electron and IR laser beams are overlapped in space and time to generate hard X-rays between 4 and 20 keV. The chamber has over two dozen motorized stages that position YAG screens with ~10 nm precision utilizing the EPICS framework for instrumentation interface. Using agile...
DAFNE, the Frascati F-factory the collider where the Crab-Waist collision scheme has been implemented and successfully tested, is presently working for a physics program in the field of exotic atoms. The present scientific program foresees the study and the characterization of the never observed before kaonic deuterium. Providing a suitable data sample for such measurement requires the...
In addition to the desired electron beam, RF photoinjectors such as the one in LCLS-II produce dark current via field emission. Left unchecked, the dark current can cause various operational issues in the accelerator, such as increased radiation, damage to accelerator components and diagnostics, and desorption of gases from vacuum chamber surfaces. In this contribution, we present measurements...
The coherent THz facility developed at NSRRC delivers superradiant radiation with wavelengths ranging from 100 – 500 um from a gap tuneable U100 planar undulator. An S-band laser-driven photocathode rf gun has been used in its 25 MeV linac system to generate a sub-picosecond high brightness relativistic electron beam via velocity bunching for emission of coherent THz radiations. However, the...
To generate the very high brightness beams in light sources, injectors based on radiofrequency photo-guns with very high peak electric fields on the cathode are used. However, this very high surface electric field on the surface of a radio frequency cavity leads to the generation of dark current due to the field emission effect which can damage the instrumentation and radio-activate...
Profile Monitor (PR) is used to observe and measure the beam profile in the Linac and transport line of the High Energy Phone Source (HEPS). To obtain more precise results, we implemented several widely used fitting algorithms in the framework Pyapas. We carried out detailed testing and comparison of these fitting methods based on simulated results and actual measurement data, respectively,...
The research and development (R&D) of the polarized electron source for the EIC has made significant progress this year. We achieved an 11 nC bunch charge of the polarized electron beam. One challenge we faced was the surface charge limit of the Distributed Bragg Reflector (DBR) GaAs/GaAsP Super Lattice (SL) photocathode. We suppressed this effect by optimizing the surface doping and heating...
The performance of superconducting radiofrequency (SRF) cavities is critical to enabling the next generation of efficient, high-energy particle accelerators. Recent developments have focused on altering the surface impurity profile through in-situ baking, furnace baking, and doping to introduce and diffuse beneficial impurities such as nitrogen, oxygen, and carbon. However, the precise role...
We present a demonstration of time-resolved diagnostics within the Coherent Electron Cooling (CeC) Pop Experiment. This technique utilizes a combination of a focusing lattice, transverse deflecting cavity, and YAG screen, along with unique analytical techniques, to precisely measure and analyze the longitudinal profile information of the CeC electron beams. Additionally, our measurement of...
The Accelerator Operations and Technology division at Los Alamos Neutron Science Center (LANSCE) is working on designing and implementing an Instrumentation and Controls System (ICS) for the Cathodes and Radio-frequency Interactions in Extremes (CARIE) project. The system will utilize open-source Experimental Physics and Industrial Control System (EPICS) developed for scientific facilities for...
Alkali antimonide epitaxy and the demonstration of very high quantum efficiencies (QEs) from ultrathin films has been an exciting development of the last few years. With goals of superb film uniformity, physical/chemical roughness, and control of stoichiometry and defect densities, comes an increased emphasis on highly capable growth systems. We report on the design and performance of a new...
The electron storage ring (ESR) in the Electron Ion Collider (EIC) requires a challenging 591 MHz fundamental 17-cavity RF system to provide up to 10 MW CW power to the beam with up to 2.5 A beam current and a wide range of voltage. In this paper, we will report the latest RF and mechanical design status, as well as the prototyping and testing results.
Bunch length is an important parameter for free-electron laser (FEL). The deflecting RF cavity was used in the beam length diagnostic instrument. In this paper, we present the design of a 3-cell rectangular deflecting RF cavity for a compact terahertz (THz) free-electron laser (FEL) facility. The 3-cell deflecting cavity has a residual orbit offset of zero as compared to single-cell deflecting...
To develop a high-power, high-efficiency electron irradiation accelerator system with an adjustable electron beam, a novel constant-gradient backward-travelling-wave (BTW) accelerating structure has been designed. This accelerator tube implements a backward-travelling-wave design, which offers the advantages of short filling time and low power reflection, which are characteristic of...
Compact accelerator systems are assuming an increasingly significant role within the domain of radiotherapy. As processing technology continues to mature, X-band accelerators have garnered extensive utilization. This study introduces a design for a side-coupled traveling-wave Ku-band accelerator tube, leveraging established processing methodologies. The envisaged particle output energy stands...
Synchrotron radiation (SR) is a phenomena found in most accelerator facilities. Whilst many look to reduce the amount of SR produced to minimize beam losses, its existence allows for several types of novel non-invasive beam instrumentation. The aim of this study is to use SR in the development of a non-invasive, high resolution, longitudinal bunch length monitor. The monitor will be capable of...
LhARA, the Laser-hybrid Accelerator for Radiobiological Applications, is a proposed facility for the study of radiation biology. The accelerator will deliver ions at ultra-high dose rates and requires real-time measurement of the dose distribution. We have developed an ion-acoustic dose mapping system that exploits the acoustic waves generated by the beam’s energy deposition. A proposed...
In a typical storage ring, the beam quality, especially the energy spread, is always relatively large for the radiation of free electron lasers.To mitigate the relatively high energy spread in the storage ring and generate FEL radiation with superior performance, we have proposed an isochronous achromat using transverse gradient undulators. In this paper, we will give a detailed theoretical...
Designing the cryogenic BPM pick-up for the Hadron Storage Ring (HSR) of the Electron-Ion Collider (EIC) is a challenging task as it needs to provide reliable beam position measurements over a variety of beam species and operating modes with various energies. The existing RHIC BPM stripline pick-up are not compatible with the planned HSR beam parameters as the HSR beam, compared to RHIC, will...
The SHINE project requires more than six hundred 1.3GHz cavities and sixteen 3.9GHz cavities for the superconducting accelerator. These cavities are from both domestic and foreign companies. The cavities fabricated in domestic companies requires correspond-ing capacity of surface-treatment. For the R&D of surface-treatment technology and mass production of SRF cavities, we have been...
Coherent synchrotron radiation (CSR) in linear accelerators (linacs) is detrimental to applications that require highly compressed beams, such as FELs and wakefield accelerators. However, traditional measurement techniques lack the precision to fully comprehend the intricate multi-dimensional aspects of CSR, particularly the varying rotation of transverse phase space slices along the...
Minimising the energy spread within the electron bunch is essential for optimal performance of free electron lasers. Wakefields from corrugated and dielectric structures have been demonstrated to be effective in bunch dechirping. However, the repercussions in beam quality are not yet well understood. Here, a dielectric wakefield structure, manufactured to be included at the CLARA facility, has...
An innovative particle tracking code is in development using the Julia programming language, utilizing the power of auto-differentiation (AD). With the aid of specifically designed truncated power series algebra (TPSA) methods and built-in Julia AD packages, this code enables automatic calculation of derivatives with respect to selected parameters of interest. This tracking code provides a...
A 217 MHz VHF gun operating in CW mode is being developed at Tsinghua University, which will be served as the beam source of the high repetition XFEL facilities and high repetition MeV UED. The cavity profile has been optimized to minimize input power, peak surface electric field, peak wall power density, and multipacting. The fabrication of the gun has been completed, and the frequency and...
The Shanghai high repetition rate XFEL and extreme light facility (SHINE) under construction is designed as one of the most advanced FEL facilities in the world, which will produce coherent x-rays with wavelengths from 0.05 to 3 nm and maximum repetition rate of 1 MHz. To achieve precise beam trajectory measurement and stable alignment of the electron and photo beams in the undulator, the...
The stress-managed cos-theta (SMCT) coil is a new concept which was proposed and is being developed at Fermilab in the framework of US Magnet Development Program (US-MDP) for high-field and/or large-aperture accelerator magnets based on low-temperature and high-temperature superconductors. A 120-mm aperture two-layer Nb3Sn SMCT dipole coil has been developed at Fermilab to demonstrate and test...
This paper describes the magnetic and mechanical design, and the main parameters of a small-aperture two-layer dipole coil made of REBCO twisted stacked-tape cable. The coil has 36-mm diameter aperture and 59-mm outer diameter. The coil turns are wound into groves in a special structure that ensures the appropriate turn location and control the level of strain and stress in the brittle REBCO...
A new electron gun is currently being designed for the S-band linac injector for ELSA. The objective of this development is to realize a new single-bunch injection mode in addition to the standard long pulse (multi-bunch) mode along with an improvement of the current beam parameters (e.g. emission current & transverse emittance) achieved by the existing gun. A dual mode design is being...
Plasma processing of superconducting radio frequency (SRF) cavities has shown an improvement in accelerating gradient by reducing the radiation due to field emission and multipacting. Plasma processing is a common technique where the free oxygen produced by the plasma breaks down and removes hydrocarbons from surfaces. This increases the work function and reduces the secondary emission...
In order to study the radio-frequency performance of superconducting materials at cryogenic temperature, we developed a TE-mode 3.9 GHz sample host cavity with a spherical bottom shape. A 11.5 cm diameter flat sample plate is enabled to attach to the cavity, with 9 cm diameter central area exposed to the RF field. In this paper, the design, fabrication and vertical test results of the sample...
The r-process fission cycle terminates the synthesis of heavy elements in binary neutron-star mergers. Fission processes of transuranium nuclides will be studied in electrofission reactions at the thrice-recirculating electron accelerator S-DALINAC*. Due to the minuscule fissile target, the experimental setup requires an active beam-stabilization system with high accuracy and a beam position...
Negative Electron Affinity (NEA) activated GaAs photocathodes are the only one capable of generating spin-polarized electron beam larger than 90%. However, the NEA layer currently made from mainstream cesium (Cs) and oxygen (O) is chemically unstable, the NEA-GaAs photocathode has a rapid QE degradation over time or electron beam. As a result, it requires an operating vacuum pressure of 1e-9...
Radiotherapy is an effective, non-invasive, widely used treatment for cancerous tumours that uses x-ray photon, electron and ion beam sources. The Laser-hybrid Accelerator for Radiobiological Applications (LhARA) is a novel laser-driven accelerator system under development that aims to prove the principle of the laser-driven approach to Particle Beam Therapy (PBT). This study aims at the...
Several groups have demonstrated that plasma processing can help to mitigate degradation of the performance of superconducting radio-frequency cavities. Plasma processing provides an alternative to removal of cryomodules from the accelerator for refurbishment. Studies of plasma processing for quarter-wave resonators (QWRs) and half-wave resonators (HWRs) are underway at FRIB, where a total of...
Photocathodes capable of producing spin polarized electrons beams are required for both high energy and nuclear physics experiments. In this work, we describe in detail the commissioning of a new apparatus for photocathode characterization which includes a retarding field Mott polarimeter for the measure of photoelectron spin polarization. We will illustrate the design of superlattice...
Niobium Superconducting RF (SRF) cavities have a theoretical peak magnetic field which limits the accelerating field to 50-60 MV/m. Presently, all SRF cavities operate in a Standing Wave (SW) resonance field in which particles experience an accelerating force alternating from zero to peak. In contrast, a resonance field in Traveling Wave (TW) mode propagates along with a structure, so...
An international collaboration between PSI and INFN-LNF has been undertaken with the aim of developing the next generation of high brightness electron sources. Through this collaboration, two unique high gradient RF photoguns that operate in the C-band frequency regime have been designed and realized. Concurrent to this, a new high power test stand at the Paul Scherrer Institut has been...
ISIS-II is the UK's proposed next-generation pulsed, spallation neutron source, and is expected to be driven by a MW-class proton accelerator. A Fixed Field Alternating gradient (FFA) machine is one accelerator configuration being considered. A demonstrator machine, called FETS-FFA, is now being actively developed. Beam Loss Monitors (BLMs) for this demonstrator are presented with the unique...
A surface treatment device has been established at the Wuxi Platform, enabling chemical polishing treatment on coupon samples. Currently, several samples treated with buffered chemical polishing (BCP) have been utilized in the investigation of nitrogen doping and medium-temperature baking mechanisms. This paper presents the development process of this device along with the experimental...
In recent years, materials irradiation processing experiments have gained significant attention due to their critical role in science and various industries, including life science, material science and electronics. Efficient and accurate dose distribution determination is essential to optimize the irradiation process. This research explores the integration of glass plate irradiation and...
Cesium antimonide (Cs3Sb) photocathodes are prime candidates to replace the metallic ones currently used to generate high brightness electron beam in X-ray free electron laser and X-ray energy-recovery linacs. Their appeal stems from their outstanding photo-emissive properties, such as low work function, that give them a high quantum yield. Whereas typical computational analyses of these...
A harp system, which is a multi-wire beam profile monitoring (MWPM) system, is planned upstream of the spallation target to make in situ calibration of beam current density configuration on the target along with beam imaging from luminescent coating on the beam entrance window at the Second Target Station (STS) of the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL)....
A far-field electro-optical (EO) setup based on a balanced detection scheme has been set up to measure the coherent synchrotron radiation (CSR) at the Karlsruhe Research Accelerator (KARA). To enable the readout with a spectrally decoded scheme (EOSD), a KALYPSO based line array camera sensitive to NIR operating at a readout rate of 2.7 MHz has been included in the set-up. In this...
The ALS Upgrade Project (ALS-U) consists in the replacement of the existing ALS storage ring and the addition of a new accumulator ring in order to decrease the horizontal beam emittance to about 70 pm·rad, resulting in an increase of two orders of magnitude in the soft X-Ray brightness. The vacuum chambers of two new rings, and of the transfer lines connecting them, will include 327 new beam...
As part of Fermilab's Proton Improvement Plan-II (PIP-II), the Fermilab Booster synchrotron will operate at a higher intensity, increasing from 4.5×10^12 to 6.7×10^12 protons per pulse (ppp). A potential challenge for achieving high-intensity performance arises from rapid transverse instabilities induced by electron clouds (EC). This research presents electron cloud simulations using PyECLOUD,...
DAΦNE is a a medium energy electron-positron collider operating in the National Laboratory of INFN at Frascati, Italy. The accelerator complex consists of two rings with an approximate circumference of 97 m. High-intensity electron and positron beams circulate and collide with the center of mass energy of around 1.02 GeV. The FCCee is an ongoing lepton collider project and its current injector...
The FCC-e+e- project foresees the realization of the most intense ever realized source of positrons providing a bunch charge of the order of 5 nC. This big number of positrons (≈3.12e+10) is produced by pair conversion following a 6 GeV electron beam bremsstrahlung on a target, and as a consequence has large divergence and energy spread. The actual design of the positron injector includes a...
A comprehensive model accurately depicts and tracks emittance and luminosity evolution in the Large Hadron Collider (LHC), considering known effects like IBS, synchrotron radiation damping, coupling and incorporating data-driven factors on emittance growth and intensity losses. Used extensively in LHC Run 2, the model is updated for compatibility with new optics and operational schemes in Run...
Intense relativistic electron beams such as those produced by the DARHT accelerators, consist of large total currents of 1.6-2 kA at modest energies in the range of 16-20 MeV. Beam envelope codes are generally used to predict the evolution of the first moment of the radial distribution (i.e. beam 2-RMS radius) assuming a constant emittance. Upon passing through a thin metal foil, such as may...
Photocathodes play an integral role in the development of electron accelerators and photon detectors. The emitted beam brightness can be limited by the surface and bulk disorder of the polycrystalline photocathode material. Epitaxial growth of photocathodes has the potential to overcome this problem and achieve high brightness electron beam. This work demonstrates the epitaxial growth of...
The ESS Linac on-going installation and technical commissioning are progressing towards the first operation at 870 MeV on the beam dump in fall 2024. Four out of five DTL tanks were commissioned with beam in the normal conducting section (NCL) and a pilot installation of 1 spoke and 1 elliptical cryomodule was conducted in the superconducting (SCL) part of the ESS tunnel in spring 2023....
The WS superconducting systems are based on scintillator detectors and wavelength shifting fibers are mounted on the beam pipe. The detectors are coupled to long haul optical fibers, which carry the signals to custom front end electronics sitting in controls racks at the surface. The acquisition chain have been characterized at IHEP (Protvino), CERN PSB, COSY Juelich and SNS before...
We present results of experimental demonstration of Plasma Cascade Amplifier with 10 THz bandwidth of Coherent electron Cooling experiment at BNL. We present results our simulation, experimental set-up and analysis of our measurements.
Schottky monitors are valuable non-invasive tools used for beam diagnostics, providing insights into crucial bunch characteristics such as tune, chromaticity, bunch profile, or synchrotron frequency distribution. This study investigates Schottky spectra at the Large Hadron Collider (LHC) through a combination of simulations and measurements. Experimental data from lead ion bunches are compared...
Coherent synchrotron radiation (CSR) is one critical beam collective effect in high-energy accelerators, which impedes the generation of high-brightness beams. The Argonne Wakefield Accelerator (AWA) facility is unique in the experimental investigation of CSR effects in complex beams, offering a large parameter space for the bunch charge and size, various bunch profiles (round and flat beams),...
The mechanisms that drive short-range modulations in the longitudinal phase space of accelerated electron bunches, otherwise known as the microbunching instability, have undergone intensive study. The various collective interactions between charged particles within the bunch, and their environment, can degrade the quality of these bunches, eventually making them unsuitable to drive light...
A minimally-invasive gas jet in-vivo dosimeter for medical treatment facilities is being developed at the Cockcroft Institute (UK), to provide full online (real time) monitoring with less frequent calibration. The monitor functions via a thin, low-density, gas jet curtain, intersecting with the beam. Online monitoring is crucial for hadron beams where acceptable dose tolerances are narrow,...
It is desirable to decrease the dimensions and power loss of accelerator components as much as possible when using accelerated charged particle beams on a rocket or satellite for ionospheric and magnetospheric research applications. We present the experimental results of a radiofrequency (RF) pillbox cavity loaded with a low-loss, high-permittivity ceramic placed concentrically within the...
Hefei Advanced Light Facility (HALF) injector comprises 40 S-band 3-meter traveling wave accelerating structures, capable of delivering electrons of full energy 2.2 GeV into the storage ring. To mitigate the emission degradation caused by dipole and quadrupole fields in the coupler cavity, the coupler design incorporates a racetrack and a short-circuit waveguide to eliminate this impact. This...
Photocathodes play key roles in supplying electron beams for diverse research facilities. Among them, semiconductor photocathodes stand out for their high quantum efficiency (QE). Typically, a high QE, long operation time, low thermal emittance and fast response time are desired for the accelerator community. However, the performance of semiconductor photocathodes is extremely sensitive to...
Ultrafast high repetition-rate laser systems are essential to modern scientific and industrial applications. Variations in critical figures of merit, such as focal position, can significantly impact efficacy for applications involving laser plasma interactions, such as electron beam acceleration and radiation generation. We present a diagnostic and correction scheme for controlling and...
The measurement of beam emittances by extracting the quadrupole mode signal from a 4 plate BPM was published at least 40 years ago. Unfortunately, in practice, this method suffers from poor signal to noise ratio and requires a lot of tuning to extract out the emittances. In this paper, an improved method where multiple BPMs are used together with better mathematical analysis is described. The...
In a world’s first, CERN recently tested Euclid’s prototype ferroelectric tuner with a superconducting cavity, and successfully demonstrated its microphonics compensation*. This Ferroelectric Reactive Tuner (FRT) stands out as the swiftest RF cavity tuner utilizing a ferroelectric ceramic tuning element, boasting an impressive response time below 100 ns. The implications of this advancement...
The occurrence of breakdown events are a primary limiting factor for future accelerator applications aiming to operate under high field-gradient environments. Experimental evidence often leads to a hypothesis that breakdown events are associated with temperature and dark current spikes on the surface of RF devices. In the past decade, there has been increased interest in unveiling the...
ESS elliptical cryomodules, CEA-INFN-STFC in-kind contribution, undergo site acceptance test at ESS Lund Test Stand (TS2). Here the Field Emission operation experience, modules performances statistics and limiting mechanism, diagnostics equipment and analysis tool are described. High energy field emission and dose rate operational challenges and long-term superconducting LINAC operational...
Cryogenic Current Comparators (CCC) are ultrasensitive DC-Beam Transformers based on superconducting SQUID technology. With the aim to provide a robust and high resolution intensity measurement for application at FAIR and CERN machines, numerous steps of optimization were carried out over the last years by a collaboration of institutes specialized on the various subtopics. Different types of...
A significant project such as the FCC-ee (with 91.17 km circumference) entails numerous challenges to ensure the stability and performance of the machine. In the pursuit of contributing to the improvement of energy consumption during its operation, the exploration of Nested Magnets (NMs) as a means to reduce synchrotron radiation has been undertaken. This paper presents first studies on the...
SRF photoguns become a promising candidate to produce highly stable electrons for UEM/UED applications because of the ultrahigh shot-to-shot stability compared to room temperature RF photoguns. SRF technology was prohibitively expensive for industrial use until two recent advancements: Nb3Sn and conduction cooling. SRF gun can provide a CW operation capability while consuming only 2W of RF...
The Future Circular Electron-Positron Collider (FCC-ee) represents a cutting-edge particle physics facility designed to further investigate the Z, W± and Higgs boson in addition to the top quark. The implementation of Nested Magnets (NMs) in the FCC-ee arc cells would maintain high luminosity and reduce its energy consumption. The use of these special magnets induces changes in the damping...
Development towards the FCC-ee "Z" machine requires optimization of sub-GHz elliptical cavities for high-gradient and high-Q operation, both in pulsed and CW mode, for application in the booster and collider portions. Previous development work validated the proposed 800 MHz 5-cell elliptical RF design, showing reasonable performance after EP treatment. However, the stringent high-Q (3.8e+10)...
Molecular-beam epitaxy (MBE) growth with lattice-matched substrates can lead to the synthesis of single-crystal alkali antimonide photocathodes[1]. Single-crystal photocathodes are expected to have not only high quantum efficiencies (QE) but also low mean transverse energy since they are usually grown as thin films. In this proceeding, we report the synthesis of potassium antimonide...
In times of climate change and with increasing challenges of the power grid stability due to unstable renewable energy sources, it is not sufficient to know the electric energy consumption of accelerator facilities. In order to optimize the operation of the research infrastructure in terms of stability, reliability and sustainability, the knowledge of the dynamics of energy consumers, and...
During the operation of a muon collider in an underground tunnel, most circulating muons decay into an electron (or positron) and a neutrino-antineutrino pair, resulting in a narrow disk of high-energy neutrinos emitted radially in the collider plane and emerging on the Earth’s surface at distances of several km. Thus, dedicated studies are required to assess any potential radiation protection...
GaAs cathodes are unique devices which generate a spin-polarized electron beam by the photoelectric effect when illuminated with a circularly polarized laser. Thin-film Negative Electron Affinity (NEA) surfaces have an essential role in spin polarized beam production, but they have limited lifetimes. In this study, we activate GaAs as an NEA cathode by evaporating Cs, Cs-O, and Sb metal on its...
The Shanghai Laser Electron Gamma Source (SLEGS) is one of the beamlines of the Shanghai Synchrotron Radiation Facility, which dedicate to producing gamma beams in the slant-scattering for the first time. After produced in the interaction area, gamma rays pass through a carefully designed Gamma Modulation System (GMS), which consists of a double collimator system, attenuator system, and...
Achieving non-invasive in-vivo dosimetry is a critical objective in the field of ion beam therapy. The comprehensive real-time characterization of the ion beam is highly desirable to ensure the safety of patients, treatment precision, and the efficiency of the treatment facility. However, current methods have limitations in terms of the information they provide and can be invasive to the beam....
A non-invasive bidirectional beam profile monitor using beam-induced fluorescence upon a thin sheet of gas has been developed at the Cockcroft Institute in collaboration with CERN and GSI. This device is particularly suited to the Electron Beam Test Stand, and as such, a bespoke gas injection has been optimized for this specific use-case to provide diagnostics unavailable to conventional...
The gas sheet ionization based diagnostic is a minimally invasive profile monitor for electron beams. In the ionization based monitor, the electron beam ionizes a neutral gas that is spatially tailored. The newly ionized particles form a footprint of the electron beam, and are imaged using an array of electrostatic lenses. The gas sheet diagnostic was conceptually tested using a 7 MeV electron...
The Proton Improvement Plan-II (PIP-II) accelerator upgrade at Fermilab represents a groundbreaking leap forward in high-energy physics research. This ambitious initiative involves enhancing Fermilab's accelerator complex by replacing the current linear accelerator with a warm front end (WFE) capable of accelerating H- beams up to 2.1 MeV. Subsequently, a superconducting linac further...
Modern accelerator facilities consistently require electron beams with improved characteristics such as shorter bunch lengths and higher brightness. To meet this demand, this study proposes a 2.4-cell photocathode electron gun, aiming to enhance the extraction electric field gradient on the cathode to produce high-quality beams. By effectively increasing this gradient, space charge effects in...
A local H- /p source is operated at the CERN Extra Low Energy Antiproton (ELENA) decelerator for commissioning the ring and subsequent electrostatic transfer lines toward the experiments. For proper optics characterization, it is important to have a detailed knowledge of the H- beam parameters at the source. Phase space tomography techniques were applied to reconstruct the beam distribution...
The Strong Hadron Cooling (SHC) for electron ion collider project requires a state-of-the-art high brightness DC electron gun. The gun is required to deliver high average current (98.5 mA), 1 mm∙mrad normalized transverse emittance and 1-2.5 nC bunch charge. In this paper, we describe the high voltage design of a DC gun with an operating voltage of 550 KV, to be conditioned up to 600 KV....
High brightness electron source is a key component for accelerator based scientific instruments. The beam brightness can be further improved with the combination of high electric field and low thermal emittance cathode. We develop an ultrahigh vacuum S-band electron gun to accommodate advanced semiconductor photocathodes, which are easily degraded in poor vacuum condition. The high power test...
The prototype fundamental power coupler (FPC) and superconducting spoke cavity for the China Spallation Neutron Source upgrade project (CSNS-Ⅱ) were manufactured before January 2023. To validate functionality, the FPC must undergo high power conditioning process prior to its assembly with the cavity. However, the high power conditioning process is quite complicated, it involves aspects like...
The AGS-RHIC injector complex includes H- ion sources at 35 keV, 750 keV RFQ and 200 MeV Linac. This report will focus on the recent upgrade of the 35 KeV Low Energy Beam Transport (LEBT) with three sources: two high-intensity magnetron H- sources and an Optically Pumped Polarized Ion Source (OPPIS) polarized H- source. There were still significant beam intensity losses in the 8 m long OPPIS...
Efficient operation of the Large Hadron Collider (LHC) relies on accurate longitudinal beam measurements to diagnose beam instabilities and verify the correctness of bunch-shaping techniques. To achieve this goal, a diagnostic system was developed to perform high-resolution measurements of longitudinal bunch profiles. High-performance oscilloscopes, synchronized to precise accelerator events,...
Two types of crab cavities, one at 197 MHz and the other at 394 MHz, are designed to compensate the loss of luminosity due to a 25 mrad crossing angle at the interaction point (IR) in the Electron Ion Collider (EIC). The Higher Order Mode (HOM) damper designs of the EIC differs from the LHC designs since in the EIC the impedance budget is tighter, especially longitudinally, and in the EIC the...
The C-band (5.712 GHz) accelerating structure with distributed coupling and four waveguide manifolds for HOM damping has been studied at Los Alamos National Laboratory to evaluate suppression of the higher-order-modes (HOMs). The HOM damping manifolds were covered by Nickel Chrome (NiCr) and had rounded edges at the interface of the waveguide with accelerating cavities. In this design study,...
Goethe University (GU), Gesellschaft für Schwerionenforschung (GSI) and Helmholtz Institut Mainz (HIM) work in collaboration on the Helmholtz Linear Accelerator (HELIAC). A new superconducting (SC) continuous wave (CW) high-intensity heavy ion linear accelerator (Linac) will provide ion beams with a maximum duty factor up to beam energies of 7.3 MeV/u. The acceleration voltage will be provided...
In order to maximize the integrated luminosity of the future circular lepton collider (FCC-ee), a top-up injection scheme is required. Amongst the four operation modes of FCC-ee, the Z operation mode has the highest stored beam energy in the collider ring with about 20 MJ per beam. Consequently, it is for this mode that the injection scheme is primarily optimized and is the focus of this...
The main challenge in the development of high intensity ion sources is, besides the space charge limited extraction, the available plasma density. Conventional plasma generators use e.g. arc discharge plasmas or RF generated plasmas. Preliminary tests are carried out on both types of plasma generators and plasma parameters are determined to create a basis for evaluation. A concept is being...
RadiaBeam has recently built and commissioned a novel C-band photo injector for high brightness Inverse Compton Source. This photoinjector is capable of producing ultra-short femtoseconds electron 250 pC bunches producing up to 300 A of beam current while maintaining the transverse emittance at a submicron level. In this paper, we describe the beam characterization of this photoinjector using...
The effect of mid-T heat treatment on flux trapping sensitivity was measured on several 1.3 GHz single cell cavities subjected to vacuum annealing at temperature of 150 - 400 $^\circ$C for a duration of 3 hours. The cavity was cooldown with residual magnetic field $\sim$0 and $\sim$20 mG in the Dewar with cooldown condition of full flux trapping. The quality factor as a function of...
Schottky monitors serve as non-invasive tools for beam diagnostics, providing insights into crucial bunch characteristics such as tune, chromaticity, bunch profile, or synchrotron frequency distribution. However, octupole magnets commonly used in circular storage rings to mitigate instabilities through the Landau damping mechanism, can significantly affect the Schottky spectrum. Due to the...
Observation of Schottky signals provides information on important beam and machine parameters, such as transverse emittance, betatron tune, and first-order chromaticity. However, the so-far developed theory of Schottky spectra does not include the impact of the higher-order chromaticity, known to be non-negligible in the case of the Large Hadron Collider (LHC). In this contribution, we expand...
The code ImpactX represents the next generation of the particle-in-cell code IMPACT-Z, featuring s-based symplectic tracking with 3D space charge, parallelism with GPU acceleration, adaptive mesh-refinement, modernized language features, and automated testing. While the code contains features that support the modeling of both linear and circular accelerators, we describe recent code...
All wires of the four CERN SPS rotational wirescanners broke when increasing the beam intensity towards the target for the LHC Injector Upgrade in 2023. Impedance and thermal studies were immediately launched, with simulations and measurements indicating that beam induced heating from resonant modes on the thin wire could be sufficient to cause these breakages. Mitigation measures to displace...
In the upcoming compact STorage ring for Accelerator Research and Technology (cSTART), LPA-like electron bunches are only stored for about 100 ms, in which the equilibrium emittance will not be reached. Therefore, to measure parameters such as bunch profiles, arrival times and bunch current losses, bunch-resolved diagnostics are needed.
The booster synchrotron of the KARA accelerator accepts...
With the recently implemented lattice tool LOCOM, which combines the precision of LOCO as well as the speed of multi-frequency AC-LOCO, it takes only a few minutes for the NSLS-II lattice measurement and correction of both linear optics and coupling. Besides, LOCOM can be applied to characterize linear optics at the extremely high chromaticity condition, thus, greatly speeding up the...
With modern accelerators encountering new physics regimes, ‘elegant’ code has added elaborate models of fringe fields, impedances, longitudinal gradient dipoles, and other elements to improve simulation accuracy. However, advanced models come with computational cost penalties. Fundamentally, elegant tracking is serial – it applies models to one particle at a time, preventing many compiler...
Diagnostics and control of beam halo along the beamline are of utmost importance for a high-intensity proton accelerator. To guide halo collimation and mitigate beam loss, halo diagnostics at different betatron phases have been proposed for the CSNS hydrogen linac accelerator. Instead of a scintillating detector, a wire scanner with a neutron-sensitive BF3 detector has been suggested,...
Jefferson Lab has an ongoing R&D program in plasma processing. The experimental program investigated processing using argon/oxygen and helium/oxygen gas mixtures. Plasma processing is a common technique where the free oxygen produced by the plasma breaks down and removes hydrocarbons from surfaces. This increases the work function and reduces the secondary emission coefficient. The initial...
The development of energetic condensation techniques has resulted in exceptional Nb film quality and improved Nb/Cu RF performance. Progress is continuously made in exploiting film forming and energetic processes to tailor the final film RF response. Convergence of parameters is emerging across techniques such as electron cyclotron resonance (ECR) and high power impulse magnetron sputtering...
The proton complex is the first piece in the Muon Collider, it comprises a high power acceleration section, a compressor and a target delivery system. For the International Muon Collider Collaboration we are investigating the possibility of having a full energy 5-GeV linac followed by an accumulator and a compressor ring and finally a target delivery system. In this paper we present the...
As part of the International Muon Collider study, a beam vacuum window is being developed at CERN. It is required for the final cooling, where the charged particles travel from the vacuum chamber to the absorber; here, the beam loses momentum to cross a second window entering in a RF cavity that increases the longitudinal momentum. The best absorber for the final cooling is hydrogen. As the...
A new bunch lengthening cryomodule based a sin-gle-cell superconducting (SC) cavity operating at the 4th harmonic (1408 MHz) of the main RF has been installed into Argonne’s Advanced Photon Source (APS) storage ring as part of the U.S. DOE APS Up-grade project. The beam-driven system will be used to improve the Touschek lifetime by increasing the bunch length by up to several times. The...
Within the context of a design study of a LINAC for ionization cooling, this paper presents the result of incorporating a scattering model in RF-Track (v2.1) for charged particles heavier than electrons. This inclusion enables simulations for applications like ionization cooling channels for muon colliders. Within RF-Track, a novel semi-Gaussian mixture model has been introduced to describe...
One of the significant sources of residual losses in superconducting radio-frequency cavities is magnetic flux trapped during the cool-down due to the incomplete Messier effect. If the trapped vortices are non-uniformly distributed on the cavity surface, the
temperature mapping revealed the “hotspots” at the location of high density of pinned vortices. Here, we performed a rf test on 1.3...
A laserwire diagnostic capable of measuring 5D phase space is to be installed on the Front End Test Stand (FETS) at the Rutherford Appleton Laboratory. The FETS beamline is a hydrogen ion source and the laserwire operates on the principle of photodetachment. A conventional tranverse laserwire is capable of 4D transverse profiling and emittance reconstruction. The FETS laserwire has a pulse...
FAIR (Facility for antiproton and ion research) is a new accelerator complex in Darmstadt, Germany which will come into operation 2027. The existing GSI accelerator will serve as an injector for the FAIR facility. GSI comprises three main injector lines equipped with different kinds of ion sources producing ion beams of a large number of gaseous and metallic elements according to the various...
In-vivo dosimetry is essential to deliver precise doses to patients in ion beam therapy. Real-time dose monitoring without disturbing the beam improves patient safety and treatment efficiency. It is critical for emerging treatment modalities like FLASH therapy due to the narrow dose tolerance. Existing real-time dosimetry devices are invasive to beam, necessitating a non-invasive dosimetry...
We present the design details and outline the construction progress of the Ionization Profile Monitors (IPMs). Two IPMs, designed for transverse beam size measurements of 70 MeV/c protons, are slated for installation—one horizontal and one vertical—in the IOTA ring. These IPMs are fast (1.8 microsecond, one turn), accurate (to better than 10%) and non-destructive diagnostics. They will play a...
Precise determination of the center-of-mass energy in the Future Circular Collider e+e- (FCC-ee) at Z and W energies can be achieved by employing resonant spin depolarization techniques, for which a sufficient level of transverse beam polarization is demanded under the presence of machine imperfections. In this study, the FCC-ee lattice has been modeled and simulated with a variety of...
LCLS-II 1-MeV CW electron source commissioning was successfully completed 2018-2020. Full 100 MeV injector system has been commissioned since summer 2022. CW RF gun and buncher operations are routinely established and e-beam is being ramped to 33 kHz now and eventually up to 1 MHz. About 0.5 μm of emittance has been achieved for 50 pC at desired bunch length. Dark current from the CW gun is...
The cabling facility at Lawrence Berkeley National Laboratory has experienced a heavy increase in workload during the US-HiLumi Accelerator Upgrade Project (AUP). Several critical components have experienced unexpected failure over the project’s lifetime for reasons at least partly attributable due to increased wear and tear on the hardware subsystems. This work presents three case studies of...
Understanding the evolution of complex systems with numerous interacting particles requires advanced analytical tools capable of capturing the intricate dynamics of the phase space. This study introduces a novel approach to longitudinal phase space density tomography in an electron storage ring, leveraging constraints imposed by the Vlasov-Fokker-Planck equation. The Vlasov-Fokker-Planck...
We present the experimental results of the longitudinal phase space measurement using the wakefields driven by the dechirper wall. In the soft X-ray line of the PAL-XFEL (Pohang Accelerator Laboratory, X-ray Free Electron Laser), the dechirper composed of 1-meter-long corrugated metallic walls is located at the upstream of the undulator section. When the electron bunch travels through the...
Charging of RF windows has historically been problematic, frequently resulting in damage to the window severe enough that the window needs to be replaced. Many attempts have been made to prevent charging and therefore improve window lifetime, the most successful and common of which is coating the window with titanium nitride (TiN). Surface coatings such as TiN rely on the secondary electron...
Single-pulse, high dynamic range BPM signal detection has been at the top of the Argonne Wakefield Accelerator (AWA) Test Facility's most-wanted list for many years. The AWA beamline's unique capabilities require BPM instrumentation with an unprecedented dynamic range, making it challenging to design and prototype a cost-effective solution. We have prototyped many different approaches over the...
The Argonne Wakefield Accelerator (AWA) facility’s main beamline -- the drive-beam linac -- can produce electron bunches over a wide range of charges (100 pC up to 100 nC). A planned upgrade of the beamline includes the installation of a symmetrized RF gun and linac cavities with the ultimate goal of improving beam brightness. Simulations were done to explore the performance of the upgraded...
We describe a high-efficiency source of muonium that can be transported as a beam in vacuum provides opportunities for fundamental muon and precision physics measurements such as sensitive searches for symmetry violation. Although PSI is currently the world leader, the intense 800-MeV PIP-II linac beam at Fermilab could provide world-class low-energy muon and muonium beams, with unparalleled...
Development of an optical fiber-based beam loss monitor (OBLM) is in progress at the Cockcroft Institute (CI), UK. The novel sensor utilizes the Cherenkov radiation (CR) emitted in optical fibers by relativistic particle showers generated in beam loss or breakdown events.
Breakdowns are a problem for high-power magnetrons, such as those in medical accelerator facilities, as damage to the...
SLAC’s LCLS-II-HE upgrade will expand the energy regime of their XFEL at high repetition rates. Due to the low emittance requirement, a superconducting QWR based electron gun was proposed by SLAC and is being developed by FRIB in collaboration with ANL and HZDR. The emittance compensation solenoid consists of two main coils, along with horizontal and vertical dipoles as well as normal and skew...
A new Rapid Cycling Synchrotron (RCS) [1] is designed to accelerate the electron bunches from 400 MeV up to 18 GeV for the Electron Ion Collider (EIC) [2] being built at Brookhaven National Laboratory (BNL). One of the two Relativistic Heavy Ion Collider (RHIC) rings will serve as the Hadron Storage Ring (HSR) of the EIC. Beam physics simulations for the RCS demonstrate that the electron beam...
Two 3.9~GHz cryomodules of sixteen cavities are required in the Shanghai high-repetition-rate XFEL and extreme light facility (SHINE) linac. They are placed before the first bunch compressor to linearize energy distribution. A total of twenty-one 3.9~GHz 9-cell cavities including two prototypes were fabricated and tested. The first two prototypes reached a Q0 of 2.9x10^9 at 13.1 MV/m and a...
The Q2 insertion quadrupoles for the High Luminosity upgrade of the LHC are currently being produced and tested. The test of the first units provides valuable information about the field quality of superconducting accelerator magnets built from Nb3Sn coils. This paper presents the results of the magnetic measurements performed on the prototype and series magnets with emphasis on field quality...
Nonlinear focusing elements can enhance the stability of particle beams in high-energy colliders through Landau Damping, by means of the tune spread which is introduced. Here we discuss an experiment at Fermilab's Integrable Optics Test Accelerator (IOTA) which investigates the influence of nonlinear focusing elements, such as octupoles, on the beam’s transverse stability. In this experiment,...
Inverse Thomson (Compton) scattering is a well-known radiation process that produces high energy and highly polarized gamma rays using a high energy electron accelerator. Linearly polarized gamma rays are generated by the interaction of a linearly polarized laser and an electron beam, while circularly polarized gamma rays are generated by a circularly polarized laser*. On the other hand, it is...
One major factor contributing to electron beam stability in a storage ring is the mechanical vibrations of magnets. At NSLS-II, we employ electromagnetic actuators to induce controlled vibrations in the support girders of the magnets. Beam position monitors distributed around the ring measure the spatial and frequency distribution of beam oscillations. The collected data is used to create and...
Distortions in the SIS100 injection kicker’s pulse time-form gives rise to beam emittance increase in the horizontal plane. Particle tracking simulations of the primary beam were carried out to try to predict the emittance at the end of the injection process for the modes of operation for antiproton (p̅) and Radioactive Ion Beam (RIB) production. The RIB cycle’s beam grew to just beyond the...
One of the main tasks for advanced experiments in modern accelerators is the generation of low-energy and high-brightness beams. The Advanced Research Electron Accelerator Laboratory (AREAL) is a linear electron accelerator based on a photocathode RF gun. The basic aim of this facility is to generate electron bunches of sub-picosecond duration with an extremely small beam emittance for...
We report updates on design work* and ongoing development of a fluorescence-based molecular gas curtain which will be used to observe the 2D transverse profile of multi-charge state heavy ion beams at the Facility for Rare Isotope Beams (FRIB). The device will produce an ultra-thin, rarefied nitrogen gas sheet and requires that the gas curtain be uniform and thin to prevent distortion of the...
In the context of the High Field Magnet programme, the 12 T Nb3Sn activity aims to design and manufacture a 2-meter-long, 12 T, cosθ, double aperture dipole. To reach magnetic fields higher than 10 T in accelerator magnets, brittle epoxy-impregnated Nb3Sn Rutherford cables are employed, which makes it difficult to predict the coil's mechanical limit and, in extenso, the magnet's performance....
As the Facility for Rare Isotope Beams (FRIB) ramps up to 400 kW, a thermal imaging system (TIS) is essential to monitor the beam spot on the production target. The TIS is an array of mirrors and a telescope in the target vacuum chamber; this relays the image through a window to the optics module outside the chamber. The design presented many challenges from alignment, to remote installation...
A Muon station for sciEnce, technoLOgy and inDustrY (MELODY) is under construction based on China Spallation Neutron Source. Up to 5Hz of proton pulses will be extracted from the RCS ring to a stand-alone target station. One surface muon and one decay muon beamline are designed to provide multi-terminals for various applications. In this report, we describe the design of MELODY and prospect...
Generative models can be trained to reproduce low-dimensional projections of high-dimensional phase space distributions. Normalizing flows are generative models that parameterize invertible transformations, allowing exact probability density evaluation and sampling. Consequently, flows are unbiased entropy estimators and could be used to solve the high-dimensional maximum-entropy tomography...
The SRF community has shown that introducing certain impurities into high-purity niobium can improve quality factors and accelerating gradients. We question why some impurities improve RF performance while others hinder it. The purpose of this study is to characterize the impurities of niobium coupons with a low residual resistance ratio (RRR) and correlate these impurities with the RF...
Ion effects present a big concern for APS-U operation. A lot of effort has been directed towards simulating and mitigating this phenomenon. Simulations predict that bunch gaps are an effective solution, especially if first and last bunches contain higher charge. However, it is desirable to minimize charge variation. This is an optimization problem - total charge should be optimized subject to...
In the Large Hadron Collider (LHC), intra-beam scattering (IBS) is one of the main drivers of longitudinal emittance growth during the long injection plateau. With the halo of the longitudinal bunch distribution being close to the separatrix, IBS consequently drives beam losses by pushing particles outside the RF bucket at the flat-bottom. As IBS and beam losses impose a requirement on the...
GaAs-based photocathodes activated to negative electron affinity (NEA) is the only existing technology that can deliver intense and highly spin-polarized electron beams for the forthcoming Electron-Ion Collider as well as enable spin-polarized scanning tunneling microscopy, ultrafast spin-polarized low-energy electron diffraction, and other cutting-edge experiments. The degree of...
Cesium antimonide photocathodes are known for their ability to generate bright electron beams for various accelerator applications. Lab-grown polycrystalline cesium antimonides as well as Cs1Sb and Cs3Sb crystals are distinguishable; however, it remains unclear how the crystalline and other material properties of each govern the main photocathode properties such as quantum efficiency and mean...
Monte-Carlo models have been successfully used to model bulk semiconductor photocathodes, such as GaAs and others. Here we present a Monte-Carlo model under development for the photoemission from semiconductor thin films, such as Cs2Te, under high acceleration field gradient. Thin films and heterostructures, as well as high photocathode gun operating gradient and cyro-cooling, are both...
We report on initial characterization of NaKSb photocathodes in the Pegasus high gradient S-band RF photoinjector. These cathodes were grown at Cornell and transported by air to UCLA. Preliminary characterization was done in the UV and yielded a quantum efficiency of 1.5% and a mean transverse energy of 0.7±0.2 eV measured by solenoid scan. Photocathode response at different wavelengths as...
Requirements for the noise in electron beams (NEB) have recently approached the Shot-noise level in some new applications. The density fluctuations of intense beams in the near-infrared (NIR) region are being measured at the Fermilab Accelerator Science and Technology (FAST) facility. The main goal of the experiment is to accurately compare the Shot-noise model with the observations of optical...
Niobium-tin has been identified as the most promising next-generation superconducting material for accelerator cavities. This is due to the higher critical temperature (Tc = 18 K) of Nb3Sn compared to niobium (TC = 9.2 K), which leads to greatly reduced RF losses in the cavity during 4.5 K operation. This allows two important changes during cavity and cryomodule design. First, the higher Tc...
The direction of particle accelerator development is ever increasing beam quality, currents, and repetition rates. Advanced control techniques using machine learning are required for the optimization and operation of such accelerators. These techniques greatly benefit from having single-shot beam measurements. However, high intensity beams poses a challenge for traditional interceptive...
Hefei Light Source (HLS) is a small and compact synchrotron light source with an electron beam energy of 800 MeV and a circumference of 66.13 m. The storage ring lattice adopts the Double-Bend Achromat (DBA) structure with 4 super periods. Considering the future upgrade of the injection system by using a nonlinear kicker (NLK), we optimize the dynamic performance of the storage ring. The...
The research is focused on finding new ways to generate high-intensity, monochromatic X and gamma-rays, surpassing the capabilities of existing methods. While Free-Electron Lasers (FEL) have limitations on photon energy, and Inverse Compton Scattering relies on powerful lasers, the search for alternatives continues. TECHNO-CLS, a PATHFINDER project funded by the European Innovation Council, is...
Bulk niobium is currently the standard material for constructing superconducting radio frequency (SRF) cavities for acceleration in particle accelerators. However, bulk niobium is limited, and new materials and surface treatments may allow greater performance to be reached. We present progress on novel materials and treatments for SRF cavity fabrication.
The Radio Frequency System-on-Chip (RFSoC) FPGA-based high-performance bunch-by-bunch beam position monitor (BxB BPM) was developed and commissioned at NSLS-II. The new BxB BPM features a 14-bit 5 Gsps ADC, directly sampling 2 ns four-button signals, and digital signal processing with a synchronized 500 MHz RF reference clock. The BxB BPM provides 32 K points of ADC raw data, 5 K turns for up...
Elettra 2.0 is the 4th generation synchrotron light source that is going to replace Elettra, the 3rd generation light source operating since 30 years in Trieste Italy, giving light to the users in 2026. In this paper we present simulation results of the beam losses. Two different way of beam losses are studied namely beam decay, which mainly concentrates on the losses due to Touschek...
In preparation for PIP2, there has been interest in running the Fermilab Booster at a higher current more indicative of the PIP2 era operation. In July 2023 an experiment was performed to study collective instabilities over the transition crossing at the Fermilab Booster. Over the transition crossing, the synchrotron tune becomes small and synchro-betatron instabilities become possible. During...
The Helium Flow Monitor System developed by Jefferson Lab and Hyperboloid LLC is designed to measure the health of cavities in a Cryomodule in real-time. It addresses the problem of unhealthy cavities with low Q0, which generate excess heat and evaporation from the 2 K super-fluid helium bath used to cool the cavities. The system utilizes a unique meter that incorporates superconducting...
The PERLE (Powerful Energy Recovery Linac for Experiments) project requires an injector capable of delivering a beam current of 20 mA at a total beam energy of 7 MeV with 500 pC bunches. These requirements present challenges for achieving the high quality beam required for the main ERL loop. At low energy and high bunch charge, the electron bunches will predominantly experience emittance...
Low energy electron bunches experience emittance growth due to space charge. This effect can lead to large emittances which are unacceptable for a facility like PERLE at IJCLab. PERLE will be an ERL test facility circulating a high current electron beam. The traditional method to reduce emittance due to this effect is already planned for the PERLE injector, this has a limit of how small the...
Single objective Bayesian optimization is used in the simulation of the compact X-ray light source (CXLS) at Arizona State University, an inverse Compton based X-ray source, to optimize the 6D electron distribution prior to final focusing at the interaction point. For inverse Compton X-ray sources, a small 6D emittance as well as a small pulse (both transversely and longitudinally) are...
The large amount of energy required to operate large-scale facilities with particle accelerators within has been considered as one of the important research topics over the past years. This sheds light on the importance of the research field of energy management that entitles, with a view to long-term operations, the implementation of smart and sustainable technologies.
One of the key...
The cathode test stand at LANL is utilized to test velvet emitters over pulse durations of up to 2.5 µs. Diode voltages range from 120 kV to 275 kV and extracted currents exceed 25 A and depend on cathode size and pulse duration. Current density measurements taken with scintillators or Cherenkov emitters produce inconsistent patterns that disagree with the anticipated beam profile. Several...
The National Synchrotron Radiation Research Center (NSRRC) has conducted a study on the magnetic circuit design of a high-temperature superconducting undulator (HTSU). This study explores the potential use of second-generation high-temperature superconducting (2G-HTS) materials in undulator magnet, which offer advantages such as higher current density and operating temperature. To evaluate the...
Synchrotron light sources often use higher-harmonic rf cavities for bunch lengthening to enhance Touschek lifetime. By adjusting the harmonic voltage, a flat-potential condition for the longitudinal voltage can be achieved, typically improving Touschek lifetime by 4 to 5 times. It is known that exceeding the flat-potential voltage results in double-peaked bunch profiles, referred to as...
A new design of fast wire scanner was installed in the CERN injector complex as part of the upgrades linked to the High-Luminosity LHC Project. Initial operations with these beams were good, but during the planned intensity ramp-up one early 2023, all four SPS scanners failed at the same time. An urgent program was put in place to understand and address this failure with experts from across...
Johannes Gutenberg University Mainz is currently constructing a new electron accelerator that employs an energy recovery scheme. The Mainz Energy Recovery Superconducting Accelerator (MESA) will provide two modes of operation: the Energy Recovery (ER) mode, which will supply an internal gas target experiment, and the Extraction Beam (EB) mode, primarily used in the P2 experiment where MESA's...
A key strategic approach to making accelerator-driven light sources more energy-efficient and sustainable is to employ superconductivity. At Karlsruhe Institute of Technology (KIT) there is a successful experience in developing and enhancing superconducting magnet systems for accelerators. That includes the design and fabrication of low and high-temperature superconducting technologies,...
The Future Circular Collider (FCC-ee) is designed to explore the Z and W± bosons, along with the Higgs boson and top quark, achieving exceptionally high luminosity. In order to minimize the energy lost per turn due to Synchrotron Radiation (SR) we explore the use of Nested Magnets (NMs) into the arcs cell. For this, it is necessary to explore the possible combinations of the different magnet...
This study primarily investigates the parameters and processes involved in depositing Nb thin films on copper cavities under DC and HIPIMS modes. For this purpose, a high-power magnetron sputtering system was designed, conducting a total of 36 experiments. Improvement and optimization of parameters such as duty cycle (under HIPIMS mode), peak current, and bias voltage were undertaken to...
The study investigates the radiation attenuation performance of five ternary glass systems with varying chemical compositions: 50P2O5-(50-x)BaO-xEu2O3, where x = 0, 1, 2, 4, and 6 mol%. It utilizes theoretical and Monte Carlo methods to determine shielding parameters such as attenuation coefficients, mean free path, value layers, electron densities, conductivity and neutron removal...
Passive streaking devices have been proposed and developed at several facilities worldwide, providing a flexible and cost-effective longitudinal bunch profile diagnostic. A passive streaker, using wakefields excited in dielectric lined waveguides, is planned to be installed in the FEBE experimental chamber at CLARA Phase-2. We present experimental tests of bunch reconstruction performed during...
In this work we demonstrate the generation of a record low root mean square normalized transverse electron emittance of less than 40 pm-rad from a flat metal photocathode – more than an order of magnitude lower than the best emittance that has been achieved from a flat photocathode. This was achieved by using plasmonic focusing of light to a sub-diffraction regime using plasmonic Archimedean...
There is a notable prospect of attaining high precision measurement of the center-of-mass energy in the Future Circular Collider e+e- (FCC-ee) at Z and W energies using resonant spin depolarization, the realization of which is based on a sufficient transverse beam polarization level. The application of harmonic spin matching schemes using closed orbit bumps holds promise for improving the...
Single crystal photocathode films promise to lower the mean transverse energy (MTE) of emitted electrons by tens of millielectronvolts, offering significant benefits for advanced light sources and electron microscopes. Traditional methods for assessing the surface quality involve accelerating electrons in a DC gap and inferring their angular distribution from the beam spot size. However, the...
With very small beam sizes at IP (several tens of nanometers in the vertical direction) and the presence of strong FFS quadrupoles in the CEPC, the luminosity is very sensitive to the mechanical vibrations, requiring excellent control over the two colliding beams to ensure an optimum geometrical overlap between them and thereby maximize the luminosity. Fast luminosity measurements and an IP...
Jinhua light source (JHLS) is a synchrotron radiation facility with the aim of the increasing requirement of user demands for industrial applications. The lattice contains 16 super-periods in order to accommodate different end users for experiments. The circumference is less than 240 m, and the natural emittance is less than 10 nm∙rad at 2.6 GeV. In this paper, we present a modified Triple...
A superconducting (SC) 1.5 GHz (3rd harmonic) cavity is being developed for lengthening bunch and improving beam lifetime in the Hefei Advanced Light Facility (HALF) storage ring. This SC cavity is excited by an electron beam with 350 mA current, 1 nC charge, and ~6.7 ps length. This contribution presents optimizations on such a SC harmonic cavity in detail. Through optimizations it has a low...
According to the high repetition rate, high brightness and other operating characteristics of SHINE, the photocathode with high quantum efficiency, low emittance, and long operating lifetime is required to produce high-quality electron beam. After solving the problems of ultra-high vacuum acquisition, photocathode plug in vacuum transmission, and photocathode preparation process, the Cs-Te...
The FCC-ee collider physics program requires a precise determination of the center-of-mass energy. The average energies of the two colliding beams can be measured by resonant depolarization (RDP) of polarized electron and positron bunches. The depolarization is achieved by an electromagnetic device, e.g., a strip line, excited at a sweeping frequency. Once the excitation frequency is equal to...
Beam Delivery Simulation (BDSIM), is a C++ program that seamlessly models particle beam transport within an accelerator model that can encompass the beam line, the accelerator's environment, and any accompanying detectors. Based on a suite of high-energy physics software including Geant4, CLHEP, and ROOT, BDSIM transforms the optical design of an accelerator into a detailed 3D model. This...
The Electron-Ion Collider (EIC) requires 34, 500 kW continuous-wave (cw), 591 MHz Fundamental Power Couplers (FPCs) to compensate the Electron Storage Ring’s (ESR) 10 MW of synchrotron radiation and other beam driven losses. This paper will describe the FPC design and fabrication status, particularly the technical challenges associated with 500 kW cw operation and the innovative design...
Field emission is one of the most important issues that limits the performance of the superconducting radio fre-quency (SRF) systems and leads to SRF cavity trips at the Continuous Electron Beam Accelerator Facility at Jeffer-son Lab. Studies have confirmed that particulates are the dominant source of field emitters and the particulates can be transported into a cavity from other parts of the...
Generation of a muon beam at a Muon Collider requires relatively short, high-charge proton bunches. They are produced in a high-average-power proton driver by first accumulating a proton beam from a super-conducting linac, then bunching the beam and finally compressing and combining the bunches into a single high-intensity proton pulse. All of these beam formation stages involve handling of...
The Electron Ion Collider (EIC), to be built at BNL, is a unique high-energy, high-luminosity, polarized electron-proton/ion collider. High-Order-Mode (HOM) damping is a big challenge for EIC electron accelerators, especially for 17 single-cell 591 MHz SRF cavities in EIC Electron Storage Ring (ESR) because of its high electron beam current (up to 2.6 A). Room temperature SiC Beamline HOM...
Alkali-based semiconductor photocathodes are widely used as electron sources and photon detectors. The prop-erties of alkali-based semiconductor materials such as crystallinity and surface roughness fundamentally de-termine the performance merits like quantum efficiency and thermal emittance. In BNL, pulsed laser deposition (PLD) was utilized to assist the growth of alkali-based photocathode...
The Fermilab Linac accepts the 0.75 MeV H- ions from the front end and accelerates them to 400 MeV for injection into the Booster. Day-to-day drifts of the longitudinal trajectory in the Linac, reconstructed from phase readings of Beam Position Monitors, are at the level of several degrees. They are believed to cause additional losses both in the Linac and Booster, and are addressed by...
This paper describes the aspects of quench detection and protective mitigation measures strategy for superconducting cavities at the European Spallation Source (ESS). A series of tests conducted at TS2 on elliptical cavities, where various methods for quench detection and mitigation measures are implemented, are described.
As one of online single-shot and non-destructive absolute measure methods with high resolution, Electro-Optical (EO) techniques have been widely utilized in Free Electron Laser to measure the longitudinal bunch profile. A bunch length monitor with 100 fs resolution is required for Shanghai Soft X-ray FEL (SXFEL) facility. The solution based on Electro-Optical Temporal Decoding (EOTD) method...
Muon production in the multi-TeV muon collider studied by the International Muon Collider Collaboration is planned to be performed with a high-power proton beam interacting with a fixed target. The design of the target area comes with a set of challenges related to the radiation load to front-end equipment. The confinement of the emerging pions and muons requires very strong magnetic fields...
Circular muon colliders provide the potential to explore center-of-mass energies at the multi-TeV scale within a relatively compact footprint. Because of the short muon lifetime, only a small fraction of stored beam particles will contribute to the physics output, while most of the muons will decay in the collider ring. The resulting power carried by decay electrons and positrons can amount to...
In Korea Multi-purpose Accelerator Complex (KOMAC) of Korea Atomic Energy Research Institute (KAERI), a 100 MeV proton LINAC is in operation and provides the proton beam for various applications since 2013. A radioisotope (RI) production beam line has developed in 2015 and the commissioning started in 2016. Recently, a beam diagnostics system for high proton beam currents of 100 μA was...
Ultra-low-charge operation of free-electron lasers down to 1 pC or even lower, requires adequate diagnostics for both, the users and the operators. For the electro-optical bunch-arrival time monitor (BAM) a fundamental design update is necessary to yield single-digit fs precision with such low charges. In 2023 a vacuum sealed demonstrator for a novel pickup structure with integrated...
A low-latency, real-time diagnostic system for the analysis of longitudinal Schottky signals in CERN’s antiproton chain has been developed. The system, installed in CERN’s Antiproton Decelerator (AD), processes the combined output of two low-noise, wideband AC beam transformers. It uses a GPU and the NVIDIA CUDA Toolkit, exploiting the directly sampled data and hardware features provided by...
SRF materials such as niobium have been extremely useful for accelerator technology but require low temperatures operation < 9 K. The development of high temperature superconductors (HTS) is promising due to their to their high critical temperature 89.5 K. This work intends to determine the high-power RF performance of such materials at X-band (11.424 GHz). Two kinds of REBCO coatings (thin...
The compact ERL (cERL) is operated at mid-energy region around 17 MeV for beam studies on industrial applications since 2017. Toward the future high power FEL source for EUV lithography, high current beam operation was demonstrated at low bunch charge after install of undulators as a first step. It is critical to reduce beam loss not to exceed 20 uSv/h outside the shield wall of the cERL...
Cherenkov threshold detectors (XCET) are used for identifying particles in the experimental areas at CERN. These detectors observe Cherenkov light emitted by charged particles travelling inside a pressurized gas vessel. A key component of the XCET detector is the 45-degree flat mirror reflecting the Cherenkov light towards the photomultiplier (PMT). A thorough analysis and optimization was...
This paper provides updates on two essential toolsets designed to facilitate the tuning and commissioning processes of the Future Circular Collider (FCC): relaxed optics and linear tuning knobs specifically for the experimental insertion regions. Motivated by the imperative need for efficient tuning strategies, we outline the construction methodology for both toolsets and present initial...
The sixth International School on Beam dynamics and Accelerator technology (ISBA23) was held for 10 days from August 3rd to 12th, 2023 at Pohang in Korea. ISBA23 was jointly hosted by Korea Atomic Energy Reꠓsearch Institute (KAERI) and Korea Accelerator and Plasma Research Association (KAPRA). After screening 83 registrant’s resumes and letters of recommendation, 70 students from Korea, Japan,...
The Karlsruhe research accelerator KARA offers a setup to measure the beam energy with resonant spin depolarization. The depolarization is excited by the stripline kickers of the bunch-by-bunch feedback system and the resonant frequency is measured via change in Touschek lifetime. Energy measurements with resonant spin depolarization are implemented as a standard routine in the control system...
Various design options have been studied and simulated using CST MICROWAVE STUDIO for a compact transverse-deflecting system proposed for diagnostics of extremely short electron bunches. The idea of the method is to use terahertz radiation, produced from optical rectification of the facility’s electron gun laser pulse. The proposed system is to be checked experimentally at the test facility...
The LCLS-II HE superconducting linac can produce multi-energy beams by supporting multiple undulator lines simultaneously. This could be achieved by using the cavity SRF tuner in the off-frequency detune mode. This off-frequency operation method was tested in 8 cryomodules at Fermilab at 2 K. In all the tests the tuners successfully achieved a frequency shift of -565±80 kHz from the 1.3 GHz...
The design of the electron-positron Future Circular Collider (FCC-ee) challenges the requirements on optics codes (like MAD-X) in terms of accuracy, consistency, and performance. Traditionally, MAD-X uses a transport formalism by expanding the transfer map about the origin up to second order to compute optics functions and synchrotron radiation integrals in the TWISS and EMIT modules....
High Energy Density Physics (HEDP) is mostly related to charged particle beams, lasers, and plasma systems. Most of the available charged particle beam systems are either of low energies (keV scale, for example, medical x-rays) or of very high energies (>GeV, for example, SLAC accelerators, CERN for fundamental research). We need MeV energy scale accelerators to study the Bragg peaks of...
High brightness electron sources are required to drive next generation light sources. This can only be achieved by photocathodes with high quantum efficiency (QE) and low intrinsic emittance, whilst also having long operational lifetimes and minimal dark current. Cesium telluride (Cs-Te) photocathodes are currently the favored material for many accelerators around the globe, typically chosen...
Ionization cooling stands as the only cooling technique capable of efficiently reducing the phase space of a muon beam within a short time frame. The optimal cooling parameters of a muon collider aim to minimize transverse emittance while simultaneously limiting longitudinal emittance growth, resulting in optimal luminosities within the collider ring. This study shows that achieving efficient...
Diamond Light Source (DLS) is a 3 GeV synchrotron facility in the UK, which has been a part of the Cherenkov diffraction radiation (ChDR) collaboration since 2017 and is now in its second phase of experiments. The current experiment aims to produce and test a one-dimensional beam position monitor (BPM) that utilizes ChDR at visible and near-infrared (NIR) wavelengths. This paper will cover the...
In autumn 2023, the FCC Feasibility Study underwent a crucial “mid-term review”. We describe some accelerator performance risks for the proposed future circular electron-
positron collider, FCC-ee, identified for, and during, the mid-term review. For the collider rings, these are the collective effects when running on the Z resonance – especially resistive wall, beam-beam, and electron cloud...
Quasi-monochromatic gamma-ray beams are produced in the laser Compton slant-scattering at the Shanghai Laser Electron Gamma Source (SLEGS) of the Shanghai Synchrotron Radiation Facility(SSRF) [1,2]. The laser Compton slant-scattering was pioneered to produce X rays as early as in 1996 [3] and has more recently been used to produced gamma rays in the MeV region at UVSOR [4]. The...
The Future Circular electron-positron Collider (FCC-ee) is a proposed accelerator with 91 kilometres circumference that should serve as a Higgs and electroweak factory, with unprecedented luminosity. Unavoidable misalignments and field errors will generate optics errors at the interaction point (IP), whose effect will be amplified by the beam-beam collisions, which will make it challenging for...
Transverse deflection structures (TDS) have been widely used as diagnostic devices to characterize longitudinal properties of electron bunches in a linear accelerator. However, the conventional TDS can only measure either the horizontal or the vertical slice envelopes of electron bunches. In order to give full control of the angles of the transverse streaking field inside of the TDS to...
A new S-band photocathode RF gun proposed for ultrafast electron diffraction (UED) has been designed and optimized. The electron gun works at pi mode and the operating frequency is 2.998GHz. The pulsed RF power loss is 3.2MW and the final kinetic energy of the electron beam is 3.5MeV. The RF gun works at high duty factor of 0.2% and the average power loss reaches 6kW. We have used ASTRA, a...
In the injector section of electron linacs, both internal space charge forces and wakefield effects influence the beam dynamics. So far, existing simulation approaches can not account for both effects simultaneously. To fill this gap, we have developed a computational method to account for both effects self-consistently*. It couples a space charge solver in the rest frame of the bunch with a...
Moving towards beam energies around 2-6 MeV in ultrafast electron diffraction (UED) experiments allows achievement of larger coherence length for better k-space resolution, while the temporal resolution is improved when shorter electron bunches are generated and the velocity mismatch between the optical pump and UED probe is reduced.
At Helmholtz-Zentrum Dresden-Rossendorf (HZDR), a series...
During the operation of BEPCII, it is found that the transverse feedback system plays an important role on the collision luminosity. In this paper, we try to simulate the effect of the transverse feedback system on beam performance and luminosity in BEPCII.
The AEgIS (Antimatter Experiment on Gravity, Interferometry and Spectroscopy) project, based at CERN's Antiproton Decelerator (AD) facility, has undergone significant enhancements, capitalizing on the increased quantity of colder antiprotons made available by the new Extra Low Energy Antiproton Ring (ELENA) decelerator. These improvements aim to create a horizontal beam and enable a direct...
The Karlsruhe Research Accelerator (KARA) is an electron storage ring for accelerator research and the synchrotron of the KIT light source at the Karlsruhe Institute of Technology (KIT). KARA features an electro-optical (EO) in-vacuum bunch profile monitor to measure the longitudinal bunch profile in single shot on a turn-by-turn basis using electro-optical spectral decoding (EOSD). A...
During Run 2 and Run 3 of the Large Hadron Collider (LHC), slow losses from electron cloud (e-cloud) effects have been systematically observed during the full duration of fills with closely-spaced proton bunches. In particular, these effects had been found to depend strongly on the crossing angle of the two beams and the value of the betatron functions in the interaction points. Due to this...
First proof-of-principle steady-state microbunching (SSMB) experiment proved that SSMB has the potential to produce high average power short wavelength light. Tsinghua University has proposed a conceptual design for the future SSMB accelerator light source. A bunch train with an average current of 1 A is required in the electron injector for the future SSMB light source with a bunch spacing of...
The Munich Compact Light Source (MuCLS)* is a compact synchrotron source based on inverse Compton X-ray scattering. This effect produces brilliant quasi-monochromatic hard X-ray radiation with rather low electron energy (tens of MeV) by colliding these electrons head-on with a laser beam. Such sources are sufficiently compact to fit into a laboratory or industrial environment enabling a more...
A pair spectrometer, designed to capture single-shot gamma spectra over a range extending from 10 MeV through 10 GeV, is being developed at UCLA for installation at SLAC’s FACET-II facility. Gammas are converted to electrons and positions via pair production in a beryllium target and are then subsequently magnetically analyzed. These charged particles are then recorded in an array of quartz...
Due to improvements of the performance of FELs, the measurements of the beam’s slice energy spread is becoming increasingly important for optimization of the brightness. Of particular interest are measurements of the uncorrelated energy spread near the gun as this determines the lower limit of the energy spread for the rest of the machine. At the Photo Injector Test facility at DESY in Zeuthen...
Iron-dominated superconducting magnets are one of the most popular and used design choices for superconducting magnetic quadrupoles for accelerator systems. While the iron yoke and pole tips are economic and effective in shaping the field, the large amount of iron also leads to certain drawbacks, namely, unwanted harmonics from the sextupole correctors nested inside of quadrupole iron pole...
This presentation will report on the status of assembling and commissioning of the Cathodes And Radio-frequency Interactions in Extremes (CARIE) C-band high gradient photoinjector test facility at Los Alamos National Laboratory (LANL). The construction of CARIE began in October of 2022. CARIE will house a high gradient copper RF photoinjector with a high quantum-efficiency cathode and produce...
Energy-recovery linacs provide high beam currents with lower RF power requirements compared to conventional machines while maintaining the high beam quality of a linac. The S-DALINAC is a thrice-recirculating accelerator operating at a frequency of 3 GHz that is capable of being operated as a multi-turn superconducting energy-recovery linac. Its efficiency is currently limited by the bunch...
The Institute of Rare Isotope Science(IRIS) has a heavy-ion accelerator facility in Daejeon, Korea. The cryomodule with quarter-wave resonators (QWR) and half-wave resonators (HWR) were also installed in the SCL3 tunnel and a beam operation test (Beam energy = 17.6 MeV/u) was performed. However, the frequency drift of the HWR is one of the failures of the beam control. Therefore, the...
RUEDI (Relativistic Ultrafast Electron Diffraction & Imaging) is a proposed facility which will deliver single-shot, time-resolved, imaging with MeV electrons, and ultrafast electron diffraction down to 10 fs timescales. RUEDI is being designed to enable the following science themes: dynamics of chemical change; materials in extreme conditions; quantum materials; energy generation, storage,...
The FCC-ee is a proposed high-luminosity circular electron-positron collider which will have beam energies spanning from 45.6 to 182.5 GeV, and will radiate up to 50 MW of synchrotron radiation power per beam. The lattice design upstream of the interaction point is based on weak dipoles and long straight sections combined with a 30 mrad crossing angle. The optics design provides a flat beam at...
Version 4 of the widely used time-dependent FEL code Genesis 1.3 has been released. The C++ code keeps the entire bunch in memory and thus allows for self-consistent effects such as wakefields or long-range space charge fields. With sufficiently allocated distributed memory, Genesis 1.3 can represent each individual electron. This solves the problem of the shot noise statistics at any...
Research is being conducted on field emission, thermionic emission, generalized electron emission, and electron emission from superconducting cavities. Generalized electron emission theories, which encompass field emission and thermionic emission, are currently under investigation. In field emission, electrons are emitted from metals due to a strong local electric field, while in thermionic...
SwissFEL is a normal conducting linear accelerator driving two separate free-electron laser (FEL) lines – one for soft and one for hard x-rays. We report jitter and correlation measurements of two electro-optical Bunch Arrival-Time Monitors (BAMs), which use directly the pulses from a mode-locked laser oscillator. The arrival-time is encoded in the amplitude of one single reference laser pulse...
The core components of the LANSCE accelerator complex – the beam source area, drift-tube and cavity-coupled linear accelerators – are more than 50 years old; a critical subsystem for beam delivery to the Lujan Center, the proton storage ring (PSR), is more than 20 years old. The proposed LAMP project is intended to begin a revitalization and update of the LANSCE accelerator complex, starting...
In late 2023 (6-8 November), Los Alamos National Laboratory hosted the “UED Opportunities for Dynamical Imaging of Materials” workshop in Santa Fe, New Mexico. The workshop was divided into two sections. The first part (1.5 days) was dedicated to material science and needs for UED imaging, and the second part (1 day) to discuss accelerator science driving next generation ultra-fast diffraction...
Elettra 2.0 is the 4th generation synchrotron light source that is going to replace Elettra, the 3rd generation light source operating for 30 years in Trieste Italy. The new ring will be giving light to the users in 2026 at 2.4 GeV. Three beam lines require very hard-x-rays i.e. photon energies at 50 keV or more with a flux of 1013 ph/sec and this can be achieved with a superconducting magnet...
At the FAIR project in Darmstadt, Germany, superconducting magnets will be utilized for the main accelerator, the SIS100 heavy ion synchrotron, and for the fragment separator Super-FRS. For SIS100, the magnets are fast ramped with a rate of up to 4 T/s while large apertures are required for Super-FRS. In total, several hundred magnets need to be produced, qualified and characterized for the...
The Mainz Energy-Recovering Superconducting Accelerator (MESA), an energy-recovering (ER) LINAC, is currently under construction at the Institute for Nuclear physics at the Johannes Gutenberg-Universität Mainz, Germany. In the ER mode continues wave (CW) beam is accelerated from 5 MeV up to 105 MeV. The energy gain of the beam is provided through 2 enhanced ELBE-type cryomodules containing two...
The SuperKEKB IR is designed to achieve extremely small vertical and horizontal beta functions at the IP. Superconducting magnets provide the focusing magnetic field required to squeeze down the beta functions. The Belle II detector solenoid field is fully compensated with the superconducting anti-solenoids on each side of the IP. For further luminosity improvement, an upgrade of the...
T-mapping diagnostic system is an indirect method to detect the internal surface of superconducting cavity during vertical testing. When superconducting cavity is powered, T-Mapping can detect the thermal instability and thermal collapse caused by defects. The goal of the project is to develop temperature detection devices that are highly accurate and easy to install. The development of the...
SRF cavities are commonly coated with superconducting materials (e.g., niobium) using magnetron sputtering. In this process, various power supplies are employed such as DC, pulsed DC or HiPIMS. The sputtered ions are ejected from the target to the cavity or sample surface with an energy dependent on the power conditions and pressure range. In this study, we investigated the efficiency of such...
Increasing the brightness of electron beams emitted from photocathodes will allow X-ray Free Electron Lasers (XFELs) to lase at larger photon energies with higher pulse energies. This will enable the development of key new accelerator capabilities. Higher electron beam brightness can be achieved by creating photocathodes with high quantum efficiency (QE) and/or low intrinsic emittance. Results...
The Chiral Belle project is a proposed project which aims to expand the capabilities of SuperKEKB and the physics goals of Belle II by injection polarized electrons into the High Energy Ring. Before the full implementation of spin rotator magnets near the interaction point, we propose to demonstrate the injection and transport of polarized electrons in the SuperKEKB Main Ring. By measuring the...
We will report on the test results of the first ever built 2-cell RF-dipole type crab cavity.
High currents of bunched electron and positron beams plan to be used in the proposed FCC-ee collider to achieve a high luminosity. Naturally, the impedance of the interaction region of the FCC must be as small as possible. Previously, a very smooth beam pipe in the interaction region was designed, and now we add necessary elements important for the beam operation, reduced backgrounds, and...
Recent advancements in electron beam compression methods have enabled the production of ultrashort electron beams at the sub-femtosecond scale, significantly expanding their applications. However, the temporal resolution of these beams is primarily limited by the flight time jitter, especially during their generation in photocathode RF electron guns. In this paper, to mitigate the impact of...
The discovery of neutrino Charge-Parity Violation (CPV) became an important candidate to explain the matter dominance in the Universe. The goal of the ESSnuSB project is to discover and measure neutrino CPV with unprecedented sensitivity*. The construction of the European Spallation Source, ESS, the world’s most intense proton source, represents an outstanding opportunity for such project to...
A first FCC final focus quadrupole prototype has been designed, constructed and tested. The prototype is of a Canted Cosine Theta type using a NbTi conductor with novel features like edge compensation and wax impregnated. It has an aperture of 40 mm and a field gradient of 100 T/m. In this paper we recall the main design features and report on the test results on field quality and the powering...
High-brightness photoinjectors generate low emittance, ultrashort electron beams that are capable of tracking dynamical states of matter with atomic-scale spatio-temporal resolutions via ultrafast electron scattering, as well as providing precisely-shaped electron beams for advanced acceleration research and large-scale facilities such as free-electron laser and inverse Compton scattering. In...
The BPM feedthroughs were manufactured and tested at the vendor and the APS lab. All feedthroughs were sorted in groups of four according to their capacitance. Four feedthroughs with close capacitance were welded to the housing in an assembly. The assemblies were measured in the APS lab to confirm their electrical performance acceptable and their x/y offsets were calculated according to VNA...
Beam instrumentation is of critical importance for the operation and optimization of modern particle accelerators. The upgrading work of CSNS has led to higher requirements for beam measurement equipment in increasing beam current research. Existing equipment, including current intensity measurement systems, emissivity measurement systems, and position measurement systems, cannot meet these...
With a circumference of approximately 91 km, the Future Circular electron-positron Collider, FCC-ee, aims for unprecedented luminosities at beam energies from 45.6 to 182.5 GeV. A major challenge is reaching its design performance in the presence of magnet misalignments and field errors. The FCC-ee optics tuning working group studies all related aspects, and applies state-of-the-art...
Single-bunch instability is studied at the Taiwan Photon Source both with and without bunch-by-bunch feedback (BBF). The instability thresholds are investigated at various chromaticities by increasing the bunch current until the instability occurs. BBF and chromaticity can increase the maximum stored bunch current and allow the tune to cross the unstable region. As the bunch current increase,...
The beam final focus system of SuperKEKB consists of 55 superconducting magnets. They are 8 main quadrupole magnets, 43 corrector magnets and 4 compensation solenoids. During beam operation from 2018 to 2022, the superconducting magnets quenched 40 times induced by the electron or positron beam hitting the superconducting coils or the other disturbances. The temperatures of the quenched...
SuperKEKB is the particle collider of electrons at 7 GeV and positrons at 4 GeV, and it is the cutting-edge collider in the luminosity frontier using the “Nano-beam scheme”. The beam colliding operation of SuperKEKB started from 2018 May, and the peak luminosity reached at 4.678×1e-34 1/cm² 1/s with quite expert beam operation. In beam operation, the vertical tune of the positron beam was...
BPM signal processing uses digital or analog down-conversion to report phase and magnitude at a single frequency, however the digitized BPM signal may contain many more harmonics and a larger bandwidth of information which may be useful. An FPGA implementation is described which captures the full bandwidth BPM signal with minimal processing and resources. This approach can be scaled to...
We will calculate tolerances for fabrication for the 197 MHz prototype crab cavity for EIC.
The “Dark Period” (DP), that is the final shutdown for the Elettra Storage Ring (SR) with its ancillary equipment and most of its beamlines, is scheduled to start on July 2nd, 2025. During the DP we will remove the complete SR lattice structure with annexed cabling, piping, and supports; the Service Area, where most of the equipment to operate the SR is installed, will be completely renovated;...
The performance and scientific reach of advanced electron accelerator applications, such as particle colliders, x-ray free electron lasers, and ultrafast electron diffraction, are determined by beam brightness. The beam brightness is constrained by the quality of photocathodes and is associated with low Mean Transverse Energy (MTE) of photoemitted electrons. To meet the requirements for...
This study focuses on the beam source for the LCLS-II-HE Low Emittance Injector (LEI) design: a state-of-the-art superconducting radiofrequency (SRF) gun. The LEI is intended to enable extending the LCLS-II-HE’s useful photon energy to 20 keV without additional cryomodules. We consider a robust two-slit emittance measurement optimized for the LEI SRF gun, compatible with the current LEI...
Especially when a high average current of 1 mA and more is required, it is important to protect photocathodes from overheating due to the absorbed laser power. Heat must be dissipated via the surrounding components and materials. This is largely limited by the low heat conductivity of usual high-voltage insulators, e.g. made of aluminum oxide. At the Johannes Gutenberg University in Mainz, we...
Following the LHC Injectors Upgrade (LIU) project at CERN, the Proton Synchrotron Booster (PSB) has been upgraded to operate with a new injection kinetic energy of 160 MeV and an extraction energy of 2 GeV. To understand the performance of the accelerator in this new energy range, a series of measurements have been conducted, especially devoted to the beam stability to ensure the optimal...
The FCC-ee could allow the measurement of the electron Yukawa coupling via direct Higgs s-channel production at ~125 GeV centre-of-mass (CM) energy, provided that the CM energy spread of this channel, can be reduced to about 5–10 MeV to be comparable to the width of the standard model Higgs boson. The natural collision-energy spread at 125 GeV, due only to synchrotron radiation (SR), is about...
This work describes improvements made to the tracking code PLACET2 to make it possible to simulate the acceleration from 250 MeV to 63 GeV in a future muon collider. This software was selected because of its unique ability to optimally simulate recirculating linacs, which are part of the proposed layout for this initial muon acceleration stage. PLACET2 has been updated to simulate...
The Micro Electron Diffraction for Ultrafast Structural Analysis (MEDUSA) beamline is a 140 keV ultrafast electron diffraction (UED) beamline currently operational at Cornell. The MEDUSA beamline specializes in the study of small samples, with electron beam probe sizes down to the single micron scale. These samples can be pumped by lasers with wavelengths ranging from IR to UV. In this...
A critical factor in determining the limit of the brightness of an electron beam is the mean transverse energy (MTE) of its source, which describes the spread in transverse momentum of electrons at the moment of emission from the source. To increase beam brightness, there has been much work in growing novel photocathodes with low MTE and high quantum efficiency (QE) near threshold...
Optimisation of thin film (TF) coating parameters for producing SRF cavities requires rapid testing of superconducting properties. A dedicated multiprobe facility built at Daresbury Lab, based on a liquid He free cryocooler, allows such measurements to be performed. The facility has vacuum tubular inserts where the sample probe is loaded and cooled with He gas. The experimental inserts were...
The magnetic measurements laboratory of the Frascati National Laboratories of INFN is one of the pole of the Innovative Research Infrastructure for applied Superconductivity (IRIS). This infrastructure aims at upgrading laboratories to carry out basic research on magnetism and superconducting materials, test of superconducting magnets, wires, tapes, cables. The LNF pole will be devoted to...
Accurate beam emittance and transverse phase space measurement are crucial for obtaining high-quality sample information in Ultrafast Electron Diffraction (UED). Traditional methods rely on general initial assumptions about the electron beam's phase space and lack specific distributions. The transverse phase space reconstruction technique based on the Computed Tomography (CT) algorithm...
This study is a review of WarpX, a particle-in-cell code optimized for high performance computing at the exascale, and its development towards the simulation of linear induction accelerators.
Superconducting materials, like V3Si, NbN, NbTiN and Nb3Sn, are potential alternatives to Nb for next generation thin film SRF cavities. In comparison to the Nb, their relatively high Tc could allow for operation at higher temperatures (≥ 4 K) and the higher critical field could lead to for higher accelerating gradients. We investigate optimum deposition parameters and substrates for V3Si,...
A novel soft X-ray BPM (sXBPM) for high-power white beams of synchrotron undulator radiation has been developed through a joint effort of BNL/NSLS-II and Stony Brook University. In our approach, custom-made multi-pixel GaAs detector arrays are placed into the outer portions of the X-ray beam, and the beam position is inferred from the pixel photocurrents. Our goal is to achieve micron-scale...
The Fermilab Side-Coupled Linac contains seven 805 MHz modules accelerating H- beam from 116 MeV to 400 MeV. Each module contains at least one wire scanner, yielding beam intensity at positions along a transverse direction. These wire scanners each contain three wires, mounted at different angles: "X", "Y", and 45° between "X" and "Y" to analyze coupling. Recently, a significant amount of...
Argonne National Laboratory is collaborating with MSU, HZDR, and SLAC on the design, fabrication, and testing of a prototype superconducting radiofrequency (SRF) gun for the LCLS-II-HE upgrade at SLAC. The gun cavity is a quarter-wave resonator with a frequency of 185.7 MHz. Despite careful calibration of the cavity field probe, there are still uncertainties in the RF measurements taken to...
Xsuite is a modular simulation package bringing to a single flexible and modern framework capabilities of different tools developed at CERN in the past decades notably MAD-X Sixtrack Sixtracklib COMBI and PyHEADTAIL. The suite consists of a set of Python modules (Xobjects, Xpart, Xtrack, Xcoll, Xfields, Xdeps) that can be flexibly combined together and with other accelerator-specific and...
High frequency RF guns cryogenically cooled to liquid nitrogen temperatures or lower offer potential for extreme accelerating electric fields exceeding 250 MV/m at the cathode. This can result in enormous increase in the brightness of electron beams obtained from RF guns but can be challenging to integrate high QE photocathodes. This talk will detail the efforts at LANL towards the realization...
The Spallation Neutron Source uses a high-power accelerator and target to produce neutrons to explore the nature of materials and energy. Running the facility at the cutting edge of technology does lead to occasional interruptions in the scientific program. We present results from a three year project aimed at exploring Machine Learning methods to improve accelerator and target reliability....
Anomalous magnetic moment (g-2) of a muon has been precisely measured by the BNL and FNAL experiments, and there is a discrepancy from the Standard Model prediction. A new measurement of muon g-2 is planned at J-PARC based on a different strategy. In the J-PARC experiment, a low emittance 300 MeV muon beam is injected into a compact storage orbit by newly developed 3-D spiral injection...
RF photo-gun are the electron beam sources of FELs or Compton facilities. They are key components and, presently, the RF technology mostly used for these devices is the S band (3 GHz) with typical cathode peak fields of 80-120 MV/m and repetition rates lower than 100-120 Hz. An innovative C-Band (5.712 GHz) RF gun aiming at reaching cathode peak field larger than 160 MV/m, with repetition...
We have performed a beam profile measurement of the ultra-slow muon for the transmission muon microscope, which is being developed at the Japan Proton Accelerator Research Complex (J-PARC). A laser ionization of thermal muonium generates the ultra-slow muon. The generated ultra-slow muon is extracted by an electrostatic lens and transported to the beam profile monitor, which consists of a...
A novel beam gas curtain (BGC) monitor was installed in the LHC as part of CERN’s High Luminosity LHC upgrade during the 2022 year-end technical stop and started to measure the profile of the proton and lead ion beams during the 2023 run. The monitor utilizes a supersonic neon beam shaped into a curtain that crosses the primary LHC beam with an angle of 45 degrees. By observing the...
Particle accelerators based on a two-beam acceleration scheme offer a path to high-accelerating fields by powering the accelerating structures using short (nanosecond) radiofrequency pulses. At the Argonne Wakefield Accelerator (AWA) facility, this approach was recently applied to an X-band radiofrequency gun and demonstrated an unprecedented electric field on the photocathode of ~400 MV/m. In...
We propose and demonstrate a time-resolved, two-dimensional temperature monitoring technique for nanocrystalline diamond stripper foils exposed to high-intensity hydrogen ion (H-) beams at the Spallation Neutron Source (SNS) accumulator ring which is independent of foil emissivity. The technique utilizes a two-color imaging pyrometer in the shortwave infrared (SWIR) spectral band to measure...
In order to prevent emittance growth during long stores of the proton beam at the future Electron-Ion Collider (EIC), we need to have some mechanism to provide fast cooling of the dense proton beams. One promising method is coherent electron cooling (CeC), which uses an electron beam to both ``measure'' the positions of protons within the bunch and then apply energy kicks which tend to reduce...
The Large Hadron Collider will soon undergo an upgrade to increase its luminosity by a factor of ~10. A crucial part of this upgrade will be replacement of the NbTi final focus magnets with Nb3Sn magnets that achieve a ~50% increase in the field strength. This will be the first ever large scale implementation of Nb3Sn magnets in a particle accelerator. This talk will present the program to...
Reduction of dynamic aperture encountered in 4th generation light sources presents a challenge for injection efficiency and commissioning. It’s possible that only after BBA and optics corrections are applied, will the dynamic aperture be sufficient for reasonable injection efficiency. Furthermore, it’s only after a circulating beam is established that BBA, BPM calibration, and other optics...
Magnets have been identified as one of the critical technologies for a proton-driven Muon Collider. Within the scope of the International Muon Collider Collaboration we have progressed in the review of requirements, and the development of concepts towards the initial engineering of several of the most critical magnets identified from our previous work. In this paper we present an update of the...
A state-of-the-art Nb3Sn-based Superconducting Undulator (SCU) has been designed and built at the Advanced Photon Source (APS) of Argonne National Laboratory in collaboration with Fermi and Berkeley National labs. Following the successful completion of its commissioning phase, this SCU in February 2023 began delivering high energy x-ray beam to APS users. The successful realization of the...
The next generation of light sources aim to provide bunch beams with small transverse emittances. A common feature in the design of light sources with small emittance lattices is the small value of the momentum compaction, which implies a short nominal equilibrium bunch length. Combined with the small transverse emittances, a short bunch length can pose severe limitations on the beam lifetime...
Non-evaporable getter (NEG) coatings are used in accelerator beamlines to create an area of distributed pumping, allowing less external pumps to be installed, and smaller diameter tubes to be used. Both giving way to greater space for magnet arrays to better control the beam within, allowing more efficient accelerators to be produced. To work, NEG coatings must be activated by heating to a set...
A method using transverse wigglers has been proposed for imparting arbitrary correlation on the transverse phase space. This concept employs transverse wigglers to introduce cosine-like modulations on the phase space. Similar to the approximation of periodic function by Fourier series, the series of properly designed cosine modulations approximates arbitrary correlations. Currently,...
Winner will talk about his career highlights and the projects he has been involved in.
Speaker will share thoughts, using examples from my own research, about why accelerator theory is important and what helps to make inventions.
Attosecond x-ray free-electron lasers (XFEL) are the brightest source of isolated sub-fs pulses, with a peak brightness that surpasses table-top high-harmonic generation sources by seven orders of magnitude. In my talk I will discuss the development of attosecond x-ray science capabilities at the Linac Coherent Light Source: from the first demonstration of isolated attosecond pulses to the...
Nonlinear lattice optimization and correction become increasingly important as storage ring light sources continue to push towards ultra-low emittances. An advanced algorithm based on machine learning technique, called multi-generation Gaussian process optimizer (MG-GPO), was applied to find optimal nonlinear lattice solutions, and was demonstrated to outperform traditional algorithms. It was...
The 3D design of large accelerators like the Large Hadron Collider (LHC) requires coordination among equipment, services, and infrastructures. As numerous systems are designed, procured, and installed, 3D integration studies are important steps at any stages of a project, starting from the conceptual phase with space reservations, envelopes and interfaces, followed by the technical design...
Starting from 2018 we have designed and created 3D printed beam correctors using two different types of FDM materials, Ultem and ASA. The design was defined based on the ergonomics of the existing machine parts, avoiding radial and longitudinal mechanical interference, and the magnetic performances to be produced. The size and configuration of the resulting windings influenced the choice of...
Neutron scattering experiments have undergone significant technological development through large area detectors with concurrent enhancements in neutron transport and electronic functionality. Data collected for neutron events include detector pixel location in 3D, time and associated metadata, such as sample orientation and environmental conditions. Working with single-crystal diffraction...
Brookhaven National Laboratory has recently been selected as the site for the Electron-Ion Collider (EIC). The EIC will consist of two intersecting accelerators, one producing an intense beam of electrons, the other a high-energy beam of protons or heavier atomic nuclei, which are steered into head-on collisions. One of the sections of the EIC beamline will require a hadron injection fast...
With a very low relative charge-to-mass ratio offset of approximately 0.065%, helium (⁴He²⁺) and carbon ions (¹²C⁶⁺) are interesting candidates for being simultaneously accelerated in hadron therapy accelerators. At the same energy per nucleon, helium ions exhibit a stopping range approximately three times greater than that of carbon ions. They can therefore be exploited for online range...
The Diamond-II storage ring upgrade will provide users with 1-2 orders of magnitude brightness increase over the existing Diamond facility, for which a quasi-transparent top-up injection scheme will be a key performance requirement [1]. The ring was originally designed to use a single-bunch aperture sharing injection scheme [2], in which short stripline kickers are used to kick the injected...
As one of the state-of-the-art radiotherapy approaches, proton therapy possesses conformal dose profiles yet expensive cost. Designing a facility with a small footprint and a high treatment efficiency is the main goal for researchers to fulfill the potential of proton therapy and make it more affordable both for vendors and patients. In this contribution, the design of a light-weight proton...
Advanced Photon Source Upgrade (APS-U) Fast Orbit Feedback (FOFB) system uses 160 fast and 160 slow corrector magnets to stabilize orbit measured at 560 Beam Position Monitors (BPM). We plan to operate both fast and slow correctors in a unified feedback algorithm at 22 kHz correction rate. Mid-ranging control is a proven approach for feedback systems with two manipulated inputs each exerting...
An exact solution for the radiation field of a particle in a helical undulator, valid for an arbitrary point in space and an arbitrary particle energy, was obtained by the partial domain method, generalized for the case of spiral motion of a particle. The interface between the regions is a cylindrical surface containing the spiral trajectory of the particle. A comparison is made with the...
We discuss the design and properties of a proposed planar cryogenic permanent magnet undulator with 20 mm period length called CPMU-20. The undulator is set to use (Pr,Nd)2Fe14B as permanent magnet material and Permendur poles and is set to be part of the planned SoTeXS beamline at the BESSY-II upgrade which will offer a unique working environment for research into energy-materials –...
A compact pulse compressor with dielectric assistance structure is proposed and simulated. The novel pulse compressor adopts a spherical resonant cavity design with dual-mode polarization mode. A dielectric sphere added at the centre of the spherical cavity can reduce the volume and weight of the pulse compressor and improve the unloaded quality factor of the cavity. A C-band compact storage...
In order for the new ATLAS Materials Irradiation Station (AMIS) to take advantage of the future multi-user capabilities at ATLAS, a pulsed kicker is needed to switch 1 MeV/u heavy-ion beams. At this energy and due to space limitations, a pulsed electric kicker is very challenging due to very high voltage requirement, and a magnetic kicker is also very challenging due to the high magnetic field...
Pulse power supply for kicker needs high di/dt. In old way, the thyristor, IGBT, SCR are chosen as the switch. We have found the photoconductive switches has nice parameters.
The Beam Coupling Impedance (BCI) is a crucial aspect in the realm of accelerator physics, as it describes the electromagnetic interactions between charged particle beams and the accelerator structure. The measurement and quantification of BCI is an essential requirement to assess and mitigate its impact, particularly when introducing new components or addressing problems within existing...
The LANSCE accelerator is an 800 MeV linear accelerator delivering beams for more than fifty years. As it has aged, maintenance and upgrades to its control system software components have become challenging and often deferred due to operational and schedule constraints. As a result, we have a wide variety of new and old software, difficult to re-use, with a large staff burden. Data is stored...
The design of accelerator lattices involves evaluating and optimizing Figures of Merit (FoMs) that characterize a beam's properties. These properties (hence the FoMs) depend on the many parameters that describe a lattice, including the strengths, locations, and possible misalignments of focusing elements. We have developed efficient algorithms to determine the multi-parameter dependence of an...
High energy colliders provide a critical tool in nuclear physics study by probing the fundamental structure and dynamics of matter. Optimizing the collider’s machine parameters is both computationally and experimentally expensive. A fast and robust optimization framework that includes both beam-beam and the detailed machine lattice will be crucial to attaining the best performance of the...
An accurate physics simulation model is key to accelerator operation because all beam control and optimization algorithms require good understanding of the accelerator and its elements. For the AGS Booster, discrepancies between the real physical system and online simulation model have been a long-standing issue. Due to the lack of a reliable model, the current practice of beam control relies...
Transitioning from the aging ALS Geo MACRO motor controller, this paper details the meticulous selection process for a new, cost-effective standard to fulfill the diverse motion requirements of the upcoming ALS-U project. Targeting primarily simple stepper motors with varying current demands, the chosen solution seamlessly integrates into the existing ALS-U EPICS environment while preserving...
This paper presents the design and status of Accumulator Ring (AR) RF Equipment Protection System (EPS) of Advanced Light Source Upgrade project at LBNL. The key components of AR RF EPS include a Master Interlock PLC subsystem handling supervisory control and slow interlocks in ms scale, an FPGA-based LLRF Controller managing fast interlocks in µs scale, a 60 kW high-power amplifier with...
High energy gamma-ray generators have the potential to be used in place of radioisotope sources, thus eliminating the security risk posed by radioisotopic sources. Euclid Techlabs design of nonradioisotopic gamma-ray source is based on ultra-compact linear accelerator with affordable magnetron RF power feeding. Wide aperture 15 cell X-band linac with embedded field emission cathode operates...
The on-axis swap-out scheme is a potential injection scheme to be adopted in the diffraction-limited storage ring light source, since it only need a rather small dynamic aperture. An accumulator is added between the booster and storage ring to allow for off-axis injection from the booster and extracting low emittance beam into the storage ring. In this paper, an accumulator ring is designed...
The folded Linear Accelerator (linac) at the Facility for Rare Isotope Beams (FRIB) presents many challenges to effectively utilizing beam loss monitors (BLMs) for machine protection. Dozens of ion chambers and neutron detectors are installed at various locations in the linac tunnel to monitor radiation from beam losses. Each device must be configured with thresholds to meet machine protection...
Beam emittance plays the crucial role in a Beam transportation system. At a fixed-target beamline off the AGS Booster Synchrotron, beam emittance is determined through measuring the beam width via a segmented multi-wire ion chamber (SWIC) and varying quadrupole strength. The width of the beam signal (as Full Width Half Max) on the SWIC passes through a minimum value and the resulting dataset...
The design, execution, and analysis of light source experiments requires the use of sophisticated simulation, controls and data management tools. Existing workflows require significant specialization to accommodate specific beamline operations and data pre-processing steps necessary for more intensive analysis. Recent efforts to address these needs at the National Synchrotron Light Source II...
The 100 mm periodic permanent magnet Wiggler (W100) was installed in the 31st straight section of the TPS storage ring in September 2020, during a prolonged shutdown of the TPS. It provides photon energy ranging from 5 to 50 keV for user experimental applications. The mechanical structure of this facility involves assembling and connecting it to the upper and lower magnetic arrays, each...
Radiation in the injection section of a synchrotron radiation facility is primarily the result of injection beam loss, which occurs each time the current is replenished, and storage beam loss, which accounts for the lifetime during routine operations. This study conducted neutron measurements by using high-sensitivity neutron detectors and obtained the total electron loss during the unfolding...
The impedance of the Large Hadron Collider (LHC) is a source of instabilities and has to be monitored closely. It is usually assessed by measuring the tune-shift vs intensity, in particular at top energy where it is the most critical, as the collimators are the closest to the beam. However, to get information on the real part of the impedance, growth rate measurements are required. These are...
A novel tuning approach, Model Coupled Accelerator Tuning (MCAT), has been applied to the separated function DTL at TRIUMF's Isotope Separator and Accelerator (ISAC). A digital twin of the rare-isotope postaccelerator is used for transverse and longitudinal tune optimizations, which are then loaded directly into the control system. Beam-based testing produced accelerated beam with a 0.26%...
High-power multi-beam klystrons represent a key component to amplify RF to generate the accelerating field of the superconducting radio frequency (SRF) cavities at European XFEL. Exchanging these high-power components takes time and effort, thus it is necessary to minimize maintenance and downtime and at the same time maximize the device's operation. In an attempt to explore the behavior of...
The automation upgrade of the photoinjector for the Compact X-Ray Light Source (CXLS) at Arizona State University is described. As the accelerator vault of the CXLS is only 10 meters long, the photoinjector drive laser is located in an enclosure inside the vault. Since ionizing radiation is present in this room during operations, it necessitates remote control of all devices used to optimize...
In this paper, the widely used RF measurement bead-pull technique for the S-band accelerating structure pre-tuning of the AREAL linear accelerator is presented. Bead-pull measurements were conducted before brazing with various group sets of accelerating cells to evaluate the effectiveness of “smart combinations” for AREAL accelerating structures. The “smart combination” technique represents...
We summarize recent experimental studies of the impedance and beam-induced heating of titanium-coated ceramic vacuum chambers used in the NSLS-II injection kickers. We installed a spare chamber (SN003) in test section C01, demonstrating that beam-induced power is effectively dissipated in the titanium coating. Equipped with 12 temperature detectors, we measured temperatures and beam currents...
Testing of space-bound microelectronics plays a crucial role in ensuring the reliability of electronics exposed to the challenging radiation environment of outer space. This contribution describes the beam optics studies carried out for the run held in November 2023 in the context of the CERN High-Energy Accelerators for Radiation Testing and Shielding (HEARTS) experiment. It also delves into...
The AGS Booster synchrotron at Brookhaven National Laboratory delivers resonant slow extracted beams to a fixed target beamline called the NASA Space Radiation Laboratory (NSRL). Experimenters at the NSRL require uniformly distributed radiation fields over large area to simulate the cosmic ray space radiation environment. The facility generates the uniform distribution using a pair of octupole...
In this paper the beam-based alignment for solenoid and quadrupole magnets in the AREAL linear accelerator is presented. The AREAL accelerator, at this stage, operates with one solenoid, one quadrupole, corrector, and dipole magnets. The adjustment of solenoid and quadrupole magnets is crucial for the stable operation of the accelerator and for forming the desired beam required for the AREAL...
The 40 MHz and 80 MHz Radio Frequency (RF) systems in the CERN Proton Synchrotron (PS) are required to perform non-adiabatic bunch shortening before beam ejection. This manipulation allows to fit the bunches into the short RF buckets of the 200 MHz Super Proton Synchrotron (SPS). Although the impedance of the cavities is strongly reduced by feedback, the detailed understanding of the...
Charge stripping is inherent for high power ion accelerators such as the FRIB LINAC. However, at high power, strippers require motion to prolong the operational life of the stripping media, or by flowing a liquid Lithium film. The charge stripping process introduces energy losses that vary with the actual Lithium film thickness, which can result in observable beam losses along the tuned...
SIRIUS, a brazilian 4th generation synchrotron light source, currently operates in top-up mode at 100mA in uniform fill. The main limiting factor for reaching higher currents is the temporary RF system in use. It is comprised of one PETRA 7-Cell cavity and two solid state amplifier towers that combined provide at most 120kW of power. By mid 2024, two superconducting RF cavities will replace...
Recent experimental measurements in the Large Hadron Collider (LHC) have shown a clear correlation between beam-beam resonance driving terms and beam losses, with a characteristic bunch-by-bunch signature. This observation creates interesting conditions to study diffusive processes. Over the past few decades, early chaos indicators, frequency map analysis and dynamic aperture studies have been...
Located in Saskatoon, Saskatchewan, Canada, the Canadian Light Source (CLS) has been operation since 2003. CLS is a 3rd generation Synchrotron Light Source operating at 2.9GeV. The CLS Booster RF system uses a 100 kW, 500 MHz solid-state power amplifier to power two 5-cell “PETRA” cavities. Recently ALBA and CLS collaborated to commission a CLS-constructed version of the ALBA Digital...
Bent crystals are a mature technology used in several applications at CERN, such as the crystal-assisted collimation system for LHC ion operation and reduction of losses during the slow extraction from the SPS by shadowing the electrostatic septum. In the future, it is planned to measure electric and magnetic dipole moments of short-lived particles with a double-crystal experiment in the LHC....
The Spallation Neutron Source (SNS) employed over 200 cold plates in its Injection Kicker and quadrupole power supplies for semiconductor cooling. Each cold plate consisted of an aluminum base with interconnected copper tubes that were brazed together. Unfortunately, the durability of these plates was compromised over time due to corrosion of the copper tubes by de-ionized water. This...
Collective wakefield and beam-beam effects play an important role in accelerator design and operation. These effects can cause beam instability, emittance growth, and luminosity degradation, and warrant careful study during accelerator design. In this paper, we report on the development of a computational capability that combines both short and long range wakefield models and a strong-strong...
In 2023, the KEK-PF 2.5 GeV ring LLRF system was replaced from a conventional analog to an FPGA-based digital system. The hardware and software of our digital LLRF system were developed by customizing the LLRF technologies established at the SPring-8 and J-PARC. In our system, we adopted the non-IQ direct sampling method for RF detection. We set the sampling frequency at 8/13 (307.75 MHz) of...
The Proton Injector for the IOTA storage ring (IPI) has been constructed at the Fermilab Accelerator Science and Technology facility (FAST). It is a machine capable of delivering 20 mA pulses of protons at 2.5 MeV. IPI will operate alongside the existing electron injector beamline to facilitate further beam physics research and the continued development of novel accelerator technologies at the...
In designing a high-power tungsten target, decay heat driven temperature rise in the spallation volume is a safety concern during maintenance and in loss of coolant accidents. As tungsten hydrates and becomes volatile in steam at above 800 ◦C, it is important to keep the target temperature below this threshold when active cooling is unavailable. Decay heat in a target is calculated with...
The impedance of in-vacuum undulators (IVU) is a significant part of the total broadband impedance determining collective effects of beam dynamics in synchrotrons. It is computationally difficult to simulate the full few-meter-long 3D structure, which includes bellows, flanges, and taper transitions with a variable gap. So, the impedance is usually calculated separately for a simplified...
The Los Alamos Neutron Science Center (LANSCE) front-end injection scheme requires an upgrade to a Radio-Frequency Quadrupole (RFQ) in order to replace the obsolete Cockroft-Waltons used in present operation. A test stand using a rod-style RFQ is under development in support of this upgrade, and conditioning of the RFQ to the expected peak and average power levels was completed to ensure its...
For cargo and vehicle inspection, where high energy linear accelerators are used, materials within radio-graphic images can be classified using their atomic number (Z). The identification and classification of materials and objects within cargo containers can be difficult, due to the nature of energy spectra and their impact on the discrimination of materials. This can also be impacted by...
The Full Remote Alignment System (FRAS) is an alignment system remotely controlled and monitored that comprises almost one thousand permanent sensors distributed along the 200 meters of equipment that will be installed in the frame of the High Luminosity LHC (HL-LHC) project on either side of the ATLAS and CMS detectors. The sensors, along with their electronics and a system of motorized...
This control system had been designed for the injection and extraction system of Shanghai Advanced Proton Therapy(SAPT). Interface of the SPELLMAN 100 kV high voltage power supply for septum magnets and Capacitor Charing Power Supply(CCPS) of the pulser for bumper magnets are including in the control design based on Programble Logic Contrllor (PLC) s7-1200. The control system realizes the...
We propose to correct nonlinear lattice optics with the closed-orbit modulation technique. Closed orbit modulation with large amplitude samples the nonlinear optics. Fitting such data measured on the machine to the lattice model with appropriate lattice parameters would reveal the nonlinear errors and provide a means for correction. The method is tested in simulation and is shown to work in...
This paper presents a cost-effective asset management system (AMS) designed to optimize the workflow of the accelerator control system for the Advanced Light Source Upgrade (ALS-U) project at LBNL. The AMS stores all essential information about equipment, including location, owner, hardware details, and firmware versions. Its user-friendly interface provides consistent access throughout the...
We present a method for coupling particle dynamics, particle-matter interaction, and hydrodynamics codes to model the effects of high-intensity electron beams in Fourth Generation Storage Rings for the purpose of machine protection. The coupled codes determine if high-energy-density conditions (>100 J/mm^3) are present in beam-intercepting components. Elegant is used to simulate the dynamics...
The Resonance Island Jump (RIJ) scheme for transition crossing in the Hadron Storage Ring of the Electron-Ion Collider is radically new, and untested. Beam experiments in RHIC will be necessary if it becomes necessary to consider the RIJ scheme as a serious alternative to upgrading the first order linear jump scheme currently implemented in RHIC. This paper outlines the theoretical foundations...
Cryogenic permanent-magnet undulators (CPMUs) have become a point of interest in the development of short-period undulators. However, electron beam-induced heating presents a significant challenge to CPMU devel-opment. The CU15, using a conduction-cooled cooling mechanism, demonstrates exceptional spectral and opera-tional performance, even when operating at small gaps with a beam current of...
In vivo studies support that the combination of protons and spatial fractionation, the so-called proton minibeam radiotherapy (pMBT), enhances the protection of normal tissue for a given tumor dose. A preclinical pMBT facility for small animal irradiation at the 68 MeV cyclotron of Helmholtz-Zentrum Berlin (HZB) will improve the understanding of this method. A two-step energy-degrading system...
The Compact X-ray Free-Electron Laser Labs (CXFEL Labs) encompass facility infrastructure that supports the operation of two beamlines, the Compact X-ray Light Source (CXLS) beamline (6-10 keV, <500 fs X-ray pulses @ 1 kHz), and the Compact X ray Free-Electron Laser (CXFEL) beamline (0.25-2.5 keV, <10 fs X-ray pulses @ 1 kHz). We present an overview of the science instrumentation and its...
The Compact X-ray Light Source (CXLS) requires the acceleration of electron bunches to relativistic energies, which collide with focused IR laser pulses to produce X-rays which are then transported to the experiment hutch. A class 4 UV laser is used at the photocathode to liberate the electrons that are generated via the photoelectric effect. During electron acceleration bremsstrahlung...
The contemporary advancement in particle accelerator technology necessitates precise control over beam manipulation for various experimental and industrial applications. One pivotal aspect of this control resides in the generation and modulation of high-voltage pulse to manipulate the trajectory and behavior of particle beams within the accelerator systems. This extensive study delves into the...
MEDICYC (MEDical CYClotron) is an isochronous cyclotron dedicated to radiotherapy which was built and commissioned in Nice, France, in 1990 by a local team aided by experts from CERN. The cyclotron accelerates H- to a maximum energy of 65 MeV and uses stripping to extract a proton beam. Its primary purpose is treating ocular melanoma by protontherapy but a significant research activity is also...
The end station for TLS beamline 07A (BL07A) primarily serves industrial applications, catering to various sample inspection requirements within the industry in multiple modes. In the past, manual switching of modes for different experiments was time-consuming, requiring the re-installment a lot components and taking long time to readjust the gas proportion for different samples. To enhance...
At Taiwan Photon Source (TPS), the main liquid-nitrogen (LN2) transfer line of length 600 m for beamline endstations was installed in 2015. It formerly supplied LN2 to maximum 24 beamline endstations. Beamline endstation 15A (TPS 15A), of which the aim is to determine 3D crystal structures from micro-scale single crystals and non-ambient conditions. We designed and self-manufactured one LN2...
This work is part of a larger program to study the effects of radiation on permanent magnets in an accelerator environment. In order to be sure that the permanent magnet samples are accurately placed, measured, and catalogued we have developed a system of sample racks, holders and measuring apparatuses. We have combined these holders and measurement racks with electronics to allow a single...
By designing a C-type nonlinear magnet, low emittance beam injection is realized on HALF
The High Energy Photon Source (HEPS) is the fourth-generation synchrotron photon source. Compared with the third-generation synchrotron photon source, the brightness is 100-1000 times higher, and the electron emittance of the storage ring is low to the diffraction limit of light. Through physical calculations, it is required that the stability of the storage ring quadrupole magnet power supply...
At the Facility for Rare Isotope Beams (FRIB) unique pre-separator wedges are required for each experiment. As the number of experiments and wedges needed increases every year, reduction in design time and increase in accuracy is critical (FY23 utilized 40 unique wedges, FY24 approx. 60 are planned, and eventually 100 annually).
Design automation is achieved by DriveWorksXpress, which...
The spin rotators (SR) are DC electromagnetic devices that produce a homogeneous magnetic field to rotate the spin of the muons in flight, which is counterbalanced by a matched perpendicular electric field to avoid the bending of the muon beam trajectory. Two identical SR will be used in the new Super-MuSR beamline to rotate the muon spin by up to 34º per device relative to the beam direction,...
A new cyclotron facility has been constructed at Thailand Institute of Nuclear Technology to provide proton beams with energy of 15-30 MeV for radioisotope production and material analysis. Due to requirements of particle induced X-ray emission (PIXE) and particle induced gamma-ray emission (PIGE) techniques that need a low-energy and low-intensity proton beam in range of 2-15 MeV and...
In recent years, plans for cancer treatment using medical RI have been progressing worldwide. The stable supply is difficult due to the aging of small nuclear reactors and dependence on imports from abroad. Manufacturing using accelerators could realize a stable supply in Japan. To give an example of Astatine-211, the production of an alpha-ray drug requires helium nuclei of 7 MeV/u or more....
The high-energy photon source (HEPS) under construction in Beijing is an excellent photon source with an emissivity better than 60pm rad. HEPS adopts on axis injection. The fast pulse power supply for booster injection adopts a topology structure of LC resonant discharge based on heavy hydrogen thyristor. The energy storage scheme of pulse capacitors adopts a design scheme of DC charging. The...
The Los Alamos Neutron Science Center (LANSCE) accelerator produces high intensity H+ and H- beams for multiple experiments in fundamental and national security science. The proposed LANSCE Modernization Project (LAMP) is evaluating necessary upgrades to enable continuous LANSCE operations in years to come. LAMP seeks to upgrade the H+ and H- 750 kV Cockcroft-Walton (CW) generators with a...
The demands of a higher brightness photon beam push the electron beam emittance of storage rings towards a diffraction-limited level. The concept of multi-bend achromat (MBA) structure and its variations, containing multiple dipoles in a cell, has been widely employed in the fourth-generation storage ring light sources. Recently, a novel concept of lattice structure, called complex bend...
A new proton injector based on the 425-MHz radio frequency quadrupole (RFQ) and interdigital H-mode drift tube linac (IH-DTL) has been designed. The injector is ~7 m long and comprises an electron-cyclotron-resonance (ECR) ion source, a low-energy beam transport, an RFQ, an IH-DTL, two triplets, a medium-energy beam transport, and a debuncher. The IH-DTL is specially designed with two tanks...
Undulators are X-ray sources which are widely used in synchrotron storage rings or in future light sources such as free-electron lasers. Due to sustainability and energy efficiency the development envisages small-scale high-field and compact undulators with short period lengths (<10 mm) and narrow magnetic gaps (<4 mm). Therefore, high-temperature superconducting (HTS) tapes, which can provide...
The novel Coupling-Loss-Induced-Quench (CLIQ) concept will be part of the quench protection system of the High Luminosity Large Hadron Collider (HL-LHC) Inner Triplet superconducting magnets at CERN. Several units of two distinct CLIQ prototype variants were produced to validate the CLIQ novel protection concept and define the system parameters for the required performance. Subsequently, these...
The Quench Heater Discharge Power Supplies (HDS) are magnet protection devices installed in the Large Hadron Collider (LHC) that, upon detection of a magnet quench, release energy into the copper-plated stainless-steel strip heaters, inducing a resistive transition all along the superconducting coils. Such a distributed internal heating ensures an even energy dissipation across the entire...
We describe the development of a novel accelerator, an electron Cyclotron Resonance Accelerator (eCRA) [1], to produce high power electron beams and X-ray beams for medical, research, sterilization, and national security applications. The several attractive features of eCRA include: a compact robust room-temperature single-cell RF cavity as the accelerating structure; continuous ampere-level...
RadiaBeam is designing and manufacturing a 15-mm period, 1.15 T field superconducting undulator. Realizing these parameters require a small gap, on the order of 5 mm. This small gap imparts a thermal management challenge due to heating from resistive walls, wakefields, upstream dipoles, and particle losses which is challenging to overcome with NbTi or NbSn3 wires without the use of liquid...
In this work, MAX FLASH system (Multi-Angle ultrahigh dose rate megavolt-level X-ray radiation system for FLASH radiotherapy) is presented. This system consists of a rapid RF power distribution network and five linacs vertically installed at different coplanar angles. The distribution network can switch all power to one terminal linac between pulses. Electron beams are accelerated to 10 MeV...
The TPS storage ring adopts a standard four kickers bump off-axis injection. This scheme is known to disturb stored beam during injections. The non-linear kicker injection concept provides a possible solution to facilitate top off injection with minimizing the oscillation of the stored beam. This non-linear kicker has zero Bx and By field in the center and an off-axis By displaced by 15 mm for...
To rule out Solid-State Power Amplifier (SSPA) modules with defects due to handmade and reduce time cost of maintenance for deployed modules, it is essential to establish a comprehensive testing platform that includes a complete quality control system. In this study, we developed a platform with function of manipulating driving power and shutting down when failures are detected.
The Safe Machine Parameter (SMP) system is an electronic hardware-based system which has been an integral part of the LHC’s machine protection strategy since it started operation. Its primary objective is to provide several parameters and interlock signals to critical machine protection users across the LHC and SPS accelerators, whilst prioritizing high reliability and availability. After...
The Electron-Ion Collider (EIC) is currently under development to be built at Brookhaven National Lab and requires cooling during collisions in order to preserve the quality of the hadron beam despite degradation due to intra-beam scattering and beam-beam effect. An Energy Recovery Linac (ERL) is being designed to deliver the necessary electron beam for Coherent electron Cooling (CeC) of the...
In this paper, the focus is on the development of a bipolar high-current correction magnet power supply for the future TPS-II permanent magnet corrector coil. The maximum output current of the prototype is speci-fied as 20 A, operating at a voltage of 48 V. This con-figuration enhances the amplitude of the trim magnetic core correction magnetic field, thereby providing greater flexibility in...
This paper investigates the design and implementation of a TPS correction magnet power supply using a combination of a linear power operational amplifier (PA05) and a pre-regulator voltage controller. The PA05 linear power operational amplifier features bipolar output, high internal power dissipation, and wide bandwidth. Utilizing a DCCT sensor as a current feedback element integrated with the...
The Hefei Advanced Light Facility (HALF) is a diffraction-limited storage ring-based light source consists of a 180 m linear accelerator and a 480 m storage ring. The RF reference signal included 499.8 MHz and 2856 MHz are generated from two phase-locked master oscillators and transmitted to the RF system, beam position monitor system, timing system and beamline station by the phase stabled...
To meet the beam commissioning requirements of the High Energy Photon Source (HEPS), a brand-new framework called Pyapas has been developed based on pure Python. All high-level applications (HLAs) for the HEPS will be developed using Pyapas. The beam commissioning of the Linac started on March 9, 2023, and the HLAs performed excellently, helping the Linac meet its design specifications...
Tantalum has been used as cladding material for water-cooled solid tungsten targets at many leading spallation neutron production facilities thanks to its high neutron yield, manageable radiation damage behavior, and excellent corrosion/erosion resistance in radiation environments. However, from a safety hazard perspective, thermal neutron capture of tantalum in spallation environments causes...
The electrostatic chopper for the new ISIS MEBT is a fast deflecting device to create gaps in the beam coming out of the RFQ, which will improve the trapping efficiency when injecting the beam into the ISIS synchrotron. The electromagnetic design of the chopper was initially developed to define its functional specifications, shape and dimensions, and it was presented elsewhere. A dimensional...
Many mature methods to measure the betatron function of a lattice rely on beam position monitor (BPM) data and the model of the whole machine. In this study, specific sections of the Relativistic Heavy Ion Collider (RHIC) were analyzed, taking advantage of BPMs separated by drift spaces near interaction points (IPs) and B3/B4 magnet sections of RHIC. This (local) approach would provide a...
In an electron linear accelerator, the continuous beam emitted by an electron gun will become an equally spaced beam train after passing through the bunching section. If the current of the beam is large, its expansion may be more intense than the case where only a single bunch is considered, resulting from the space charge forces between different bunches. In this article, using an algorithm...
A Laser Assisted Charge Exchange (LACE) injection in the Spallation Neutron Source (SNS) is under development. By utilizing powerful lasers and magnetic fields, electrons are stripped out of the H- beam without foils. Such a process avoids any foil-based charge exchange injection problems, such as foil degradation and beam loss, especially for future multi-megawatt power beams....
Particle accelerators are among the largest and most expensive scientific facilities. Constant monitoring of data from a diverse array of diagnostics is imperative to ensure proper operational parameters—such as beam parameters, power sources, cooling systems, etc. Detecting equipment failure within this data stream is challenging due to the accelerator parameters gradually shifting over time...
The use of glassy carbon (GC) as a future nuclear waste storage material depends on its capability to retain all radioactive fission products found in spent nuclear fuels. Ruthenium (Ru) is one of the most important fission products in nuclear reactors. This work investigates the effects of implantation temperature and annealing on the structural evolution and migration of Ru implanted in GC....
A new high-luminosity Electron-Ion Collider (EIC) is being developed at BNL. Beam collisions occur at IP-6, involving two rings: the Electron Storage Ring (ESR) and the Hadron Storage Ring (HSR). The vacuum system of both rings is newly developed and impedance optimization is progressing. Beam-induced heating and thermal analysis are performed for both rings to manage and control thermal...
The synchrotron facility and experimental station in the National Synchrotron Radiation Research Center (NSRRC) uses many electrical appliances, the improper use of which can cause fires, resulting in property damage and personal injury. Therefore, the usage of these electri-cal appliances must be assessed.
This study conducted a comprehensive inspection and evaluation of the electrical...
The replacement of radionuclides used for cancer therapy with accelerators offers several advantages for both patients and medical staff. These include the elimination of: unwanted dose, specialized storage and transportation, and isotope production/replacement. Several electronic brachytherapy devices exist, and typically utilize an x-ray tube around 50 keV. These have primarily been used for...
The experience gained at CERN by the R&D for LINAC4 has been exported to medical and societal applications. With an innovative design of the Radio Frequecy Quadrupole (RFQ) at high frequencies, it is possible to build very com- pact structures, reproducible in industry and with the po- tential of full portability. ELISA (Experimental LInac for Surface Analysis) is a linear proton accelerator...
The purpose of this paper is to estimate the conducted and radiated Electromagnetic Interference (EMI) for subsystems in the SXFEL LINAC. A spectrum analyzer system with a wide frequency range of 9 kHz to 3 GHz was conducted to measure the EMI spectrum of pulse modulator and klystron system. The radiated EMI was tested by electric and magnetic field probe. A stray current was tested by wide...
In the context of the HL-LHC upgrade, RF Crab Cavities (CCs) are one of the key components. Due to the increased intensity, the collider will operate with a large crossing angle scheme and these CCs will be used to counteract the geometrical reduction factor coming from the crossing angle. Amplitude and phase noise injected from the Low-Level RF, are known to induce transverse bunch emittance...
The SLRI Beam Test Facility (SLRI-BTF) is able to produce electron test beam with maximum energy of 1.2 GeV and various intensities from a few to millions of electrons per repetition. The main components of the SLRI-BTF are the Siam Photon Source (SPS) injector consisting of a 40-MeV linear accelerator, a low-energy transport beamline, a synchrotron booster increasing electron energy to 1.2...
As the China Spallation Neutron Source (CSNS) Phase II project upgrades beam power to 500 kW, maintaining horizontal beam orbit stability necessitates more precise output current from the main magnet power supplies. The existing control strategy, suited for 100 kW extraction power, falls short of the higher precision requirements for the output current, characterized by a quasi-sinusoidal...
The High Energy Physics, Cosmology, Astroparticle Physics, and Hadron and Nuclear Physics (HECAP+) communities make use of common and similar experimental infrastructure, such as accelerators and observatories, and rely similarly on the processing of big data. Our communities therefore face immense challenges to improving the sustainability of our research. This poster presents the grassroots...
In the radio frequency system of a synchrotron accelerator, precise modulation of signals in the radio frequency cavity is crucial for achieving a stable acceleration electric field. The National Synchrotron Radiation Research Center's (NSRRC) Taiwan Photon Source (TPS) underwent a significant upgrade in 2019, transitioning from analog to digital control for the low-level radio frequency...
The J-PARC MR synchrotron began high repetition operation with shortened accelerator cycles in 2022. So far, FX has been supplying a 2x10e+14 proton per pulse (ppp) beam to the Neutrino Experimental Facility with a repetition rate of 1.36 seconds, and SX has been supplying a 0.6x10e+14 ppp beam to the Hadron Experimental Facility with a 5.20 seconds repetition. The amount of heat per...
Ernest Courant Traineeship is a consortium of Stony Brook University, Brookhaven National Laboratory and Fermi National Accelerator Laboratory with goal of workforce development in Accelerator Science and Engineering at the Center for Accelerator Science and Education (CASE, SBU). We present the curriculum of the traineeship and advantages provided by access to large and medium accelerators,...
The Advanced Photon Source (APS) has recently installed and begun commissioning of a hybrid seven-bend-achromat design to replace the original storage ring. As in many recent storage ring designs, the APS Upgrade* (APS-U) magnets are closely spaced compared to those in third-generation storage rings. Calculation of "cross-talk" effects for such closely-spaced magnets can be time-consuming if...
Due to the small vacuum apertures, impedance serves as a significant cause of beam instabilities in the 4th generation storage ring. These instabilities are directly affected by the bunch charge, thereby placing a limit on the maximum achievable beam current within the storage ring. The Korea-4th generation storage ring (Korea-4GSR) is currently under construction with the aim of reaching a...
European Laboratories for Accelerator Based Sciences (EURO-LABS), a program for research infrastructures services advancing the frontiers of knowledge, aims to provide unified transnational access (TNA) to leading Research Infrastructures (RI) across Europe. Taking over from previously running independent TNA programs, the new program brings the nuclear physics, the high-energy accelerator,...
The Nonlinear Injection Kicker (NIK) scheme for the Taiwan Photon Source (TPS) has been under study as a potential replacement for the current bump-based injection scheme. The evaluation encompasses three phases of the NIK scheme. In phases I and II, the orig-inal Booster to Storage Ring Transfer Line (BTS) is utilized to assess the performance of a prototype NIK. Phase III involves the...
To reduce the dark current and secondary electron multiplication in conventional conducting accelerator cavities, and to improve the quantum efficiency of copper photocathodes, thereby achieving higher beam quality and enhancing the acceleration gradient and operational stability of accelerators, Tsinghua University designed a 13.56 MHz internal coil-type capacitive discharge plasma...
In this paper, we present a concise measurement of the Second-Order Transit Time Factor(TTF) of the relativistic electron beams within the bunching cavity of the Coherent Electron Cooling (CeC) Pop Experiment. Our study outlines a specialized measurement methodology that tackles the unique challenges posed by the CeC accelerator environment. The results not only provide significant insights...
Nonlinear integrable optics are a promising alternative approach to lattice design. The integrable optics test accelerator (IOTA) at Fermilab has been constructed for dedicated studies of magnetostatic elliptical elements as described by Danilov and Nagaitsev. The most compelling verification of correct implementation of the NIO lattice is direct observation of the analytically expected...
In the SIS18 heavy-ion synchrotron at GSI, RF beam phase feedback systems are developed and tested with beam for the damping of coherent longitudinal bunch oscillations. In particular, a beam phase control system is currently commissioned for the damping of longitudinal dipole oscillations. The feedback system has to cope with both, a large RF frequency span (400 kHz to 5.4 MHz) and...
An upgrade to the Continuous Electron Beam Accelerator Facility (CEBAF) at the Thomas Jefferson National Accelerator Facility (JLAB) is anticipated to provide an electron beam of over 20 GeV using the existing superconducting-RF linear accelerator and new fixed-field alternating (FFA) gradient recirculation arcs made up of Halbach-style permanent magnets. In the current design, the FFA arcs...
In order to miniaturize ion injectors for particle therapy, a design of ion injectors based on a 325 MHz operating frequency was completed. The LINAC was consist of a 2.0 m length RFQ and a 3.8 m length IH-DTL, which was designed to accelerate 12C4+, 3H+, 3He+ and 18O6+ beams to 7 MeV/u. The RFQ cavity and the first DTL tank was been manufactured using aluminum. This paper gives an overview of...
Niobium cavities are key elements in superconducting radiofrequency (SRF) accelerators. Despite increasing worldwide demand, global commercial production capacity is limited to a small number of vendors with virtually no US-based turn-key suppliers. As SRF technology expands across scientific research, industry, and technology sectors, the demand for their production is expected to rise even...
The Continuous Electron Beam Accelerator Facility (CEBAF) is a 12 GeV recirculating electron accelerator at the Thomas Jefferson National Accelerator Facility (JLAB). Major upgrades to the accelerator are being investigated which include a new 650 MeV injection beamline and state-of-the-art fixed-field alternating (FFA) gradient recirculation arcs. The upgrade will extend the energy of the...
Permanent magnets are attractive options for nano focusing and $q$-magnification in MeV ultrafast electron diffraction (MeV-UED) due to their high field strengths and compact footprints. In this work, we present field characterization of axially and radially magnetized neodymium rings. Such rings can produce strong axisymmetric focusing and naturally fulfill the requirement of stigmatic...
The Targeted Alpha Tumor Therapy and Other Oncological Solutions (TATTOOS) project at the Paul Scherrer Institute aims to produce large quantities of radioisotopes (in the range of GBq), mainly Terbium-149, for the promising Targeted Alpha-particle Therapy (TAT) against metastasized cancer. To facilitate this, a new electromagnetic separator is currently being designed. Comprising two...
Radio Frequency Knock Out (RF-KO) resonant slow extraction is commissioned at the Cooler Synchrotron (COSY) Jülich for the first time to extract the stored beam and deliver spills with constant particle rates to the experiments. Therefore, transverse RF excitation generated with a software-defined radio is applied to control the extraction rate. A built-in feedback system adjusts the...
During operation, the Future Circular electron-positron Collider (FCC-ee) will be subject to vibrations from mechanical sources and ground motion, resulting in errors with respect to the closed orbit. To achieve physics performance, luminosity and beam lifetime must be kept to design specifications. To correct for errors at the IPs, a fast feedback system is required. In this paper, we present...
We present a design of the proton FLASH radiation therapy facility using the Brag peak to be built at Stony Brook University Hospital at the Radiation Oncology Department. It includes an injector using a commercially available injector cyclotron (10-30 MeV), fixed field alternating (FFA) gradient beam lines, permanent magnet Fixed Field Alternating Gradient non-scaling variable transverse...
At the Photo Injector Test facility at DESY in Zeuthen (PITZ), an R&D platform for electron FLASH cancer radiation therapy and radiation biology is being prepared: FLASHlab@PITZ. The design of the full beamline with optimized beam properties was finished; the setup is currently being finalized and the mechanical design and manufacturing is underway. The beamline runs in parallel to the SASE...
By using a high-energy electron beam (beam energy of several hundred MeV) strongly focused on the tumor lesion area, radiotherapy can be performed with a relatively simple beam generation and handling system while resulting in a suitable shape of the deposition energy curve in a tissue-like material. Quadrupole magnets are typically used for beam focusing, which makes the beam delivery system...
In FRIB we use chopper in the low energy beam line for beam power controls. As appropriate functioning of chopper is critical for both beam operation and machine protection, an FPGA-based chopper monitoring system was developed to monitor its operation for fixed duty cycle operation and has been in use to support operation. The chopper monitor shuts off beam promptly at detection of a...
The FRIB carbon disc target receives the primary beam at high power and produces rare isotope fragments. To avoid damaging the carbon disc target, it is rotated at 500 RPM and cooled. If these thermal management mechanisms fail, local temperatures on the target can increase to the point of material sublimation and structural failure. A thermal imaging camera was temperature calibrated and...
The PIP-II project currently under construction at FNAL will replace the existing 400 MeV normal conducting linac with a 800 MeV superconducting linac. The beam power in the downstream rapid-cycling Booster synchrotron will be doubled by raising the machine cycle frequency from 15 to 20 Hz and by increasing the injected beam intensity by a factor 1.5. This has to be accomplished without...
Laser plasma accelerators have a great potential to accelerate a charged particle beam to high energy within a short distance due to their extraordinarily high accelerating gradient. However, in order to effectively use the laser plasma accelerator, the input beam has to be moving at relativistic velocities, with a duration 100 femtoseconds or less. In this study, we propose a scheme to...
Compact SRF industrial linacs can provide unique parameters of the beam (>1 MW and >1-10 MeV) hardly achievable by normal conducting linacs within limited space. SRF technology was prohibitively expensive until the development of conduction cooling which opened the way for compact stand alone SRF systems suitable for industrial and research applications. Limited cooling capacity puts strict...
Generating layers of symmetrical optical caustic beams using a specific configuration of cylindrical lenses is an innovative idea with potential application in precision alignment and other fields. The technique allows the generation of layers of non-diffracting beams with opposite accelerating directions. This approach can be extended in two dimensions or to create rotationally symmetric...
The electron lens for space charge compensation is an R&D project to increase the primary beam intensity and thus the accelerator efficiency of SIS18 and eventually SIS100 for FAIR operation. As a first step, the principle of space charge compensation will be demonstrated in SIS18 with a single lens, aiming at a tune shift of 0.1 for several ion species. However, the design should also be...
The goal of the High Luminosity-Large Hadron Collider (HL-LHC) Inner Triplet (IT) String test, is to validate the assembly and connection procedures and tools required for its construction, to assess the collective behavior of the superconducting magnet chain in conditions as close as possible to those of their operation in the HL-LHC and to provide a training opportunity for the equipment...
The CERN Accelerator Beam Transfer group has recently launched a study to investigate the life cycles of pulsed septum magnets. The development is aiming to enhance the prediction of anomalies, leading to reduced life cycles of these beam transfer equipment. For this reason, the standard vacuum operated, direct drive septa magnet has been chosen to investigate critical design features. In the...
We report the successful high power RF conditioning of the revised 175 MHz FRANZ RFQ up to 80 kW CW, as well as successful beam commissioning up to 700 keV in pulsed operation. After a revision of the RFQ electrodes, the RFQ accelerates protons from 60 keV to 700 keV. The Frankfurt Neutron Source FRANZ will be a compact accelerator driven neutron source utilizing the 7Li(p,n)7Be reaction with...
The high-voltage nanosecond power supply is required to power the kicker in the injection system of the Hefei Advanced Light Facility (HALF). The amplitude of this power supply is ≥ ±10 kV and its pulse width is about 2 ns. The feasibility of the actual project is theoretically verified by simulation in this paper.
Thomas Jefferson National Accelerator Facility (Jefferson Lab) is currently studying the feasibility of an energy upgrade based upon Fixed-Field Alternating Gradient (FFA) permanent magnet technology. The current plan is to replace the highest-energy recirculation arcs with FFA arcs, increasing the total number of beam recirculations, thus the energy. In order to accommodate multiple passes in...
The linac at the Los Alamos Neutron Science Center (LANSCE) provides beam to five user facilities with various beam energy and timing patterns. While the other four facilities have the same 201.25-MHz micro-bunch structure created by a pre-buncher and main-buncher pair, the Weapon Neutron Research (WNR) requires significantly higher charge per micro-bunch. This is achieved via adding a low...
The integrable optics test accelerator (IOTA) at Fermilab was designed to operate a nonlinear magnet satisfying the Danilov-Nagaitsev integrable potential. At large excitations of this nonlinear magnet the small amplitude vertical tune crosses the integer resonance. At this point the beam splits vertically into two separate beamlets whose separation distance depends on the nonlinear strength....
The Shanghai Synchrotron Radiation Facility upgrade (SSRF-U) lattice is a 4th generation, 3 GeV, upgrade plan for SSRF. It aims to reach the diffraction limit while keeping the existing beam lines and spaces. The majority of insertion devices (IDs) in operation of current SSRF will be considered as the ID scheme in SSRF-U. The kick-map method has been used to build ID models, including the...
SIRIUS is the Brazilian 4th generation synchrotron light source. Currently, SIRIUS is in its Phase 1 stage of the project, with 14 beamlines proposed, some of which are already used by external users. Recently, the SABIÁ beamline underwent a transition where its commissioning insertion device (ID) was replaced by the beamline’s titular ID, an in-house developed DELTA undulator. This device...
This paper presents the results of the IMPACT-T simulation conducted for the latest iteration of the Coherent Electron Cooling (CeC) Pop Experiment at Brookhaven National Laboratory (BNL). The CeC experiment aims to demonstrate the principles of CeC, a rapid cooling technique designed for high-energy hadron beams. In addition to presenting simulation results for the current lattice parameters,...
An eddy-current design is used for the septum in HALF (Hefei Advanced Light Facility), with the whole cores located in a vacuum chamber. The stored beam passes through a copper vacuum pipe which set in the vacuum chamber. Two types of connections between the copper pipe and the flanges at both ends of the chamber were considered. The impedance calculations were done, and the wake-field, heat...
ECHO3D has been used for calculating the geometric impedance for several beamline vacuum components in the hadron storage ring (HSR) of the EIC (Electron-Ion Collider) in the past few years. In this paper, we present the geometric impedances calculated from ECHO3D for the beam screen with pump slots, the polarimeter and the bellow with pump ports in the HSR. We also discuss some findings while...
The beam coupling impedance is a key design parameter for all accelerator structures. Recently, we have introduced a novel simulation approach for impedance calculations in 3D-geometry. Unlike conventional methods, this approach is based on the solution of Maxwell’s equations in the frequency domain using a high-order finite element technique. The main challenge for all impedance simulations,...
Boosters in synchrotron injector systems have traditionally had more relaxed designs than storage rings, and consequently impedance has not been considered an important factor in their designs. In 4th generation light sources like Diamond-II, it is desirable to increase the extracted charge per shot to reduce filling times and enable advanced injection schemes. As such, the vacuum chamber...
We present an impedance model of the Fermilab Recycler ring using PyHEADTAIL. The model is constructed by incorporating analytical expressions for the wakefields of beamline components that contribute significantly to impedance. The effects of indirect space charge are included as an inductive impedance. Benchmarking against measured coherent Betatron tune shifts, the impedance model is found...
The beam gas ionization monitors (BGIs) are non-destructive instruments to measure the transverse beam profiles. With the goal to double the beam intensity in the injector chain for the High-Luminosity Large Hadron Collider (HL-LHC), any element contributing to the overall beam coupling impedance requires an in-depth impedance evaluation from the design stage. This paper presents the beam...
This paper introduces the strategy for operating the cryogenic system of the ESS superconducting LINAC, emphasizing the integration of individual cryomodules and valve boxes within an unified system. The study focuses on the practical implementation of this strategy at Test Stand 2 (TS2) as a pilot project, validating the proposed control system in a real-world setting. The paper evaluates the...
The elliptically polarized undulator with a period length of 56 mm, called EPU56, is part of the Taiwan Photon Source (TPS) phase-III beamline project. Its control system is built within the EPICS framework using motion controllers and EtherCAT. The control systems of EPU56 include a safety interlock system, which automatically stops movement based on limit switches, torque limit...
The hard-edge model for a quad field distribution is widely assumed in particle simulations at the early design phase of beam transport lines or circular accelerator rings to quickly evaluate their beam optics. However, the model assuming a rectangular field distribution even with an effective length is not an appropriate approximation for low-energy beams (<50 MeV). This approximation is...
Identifying the source of beam loss events in the CEBAF accelerator can be a challenging task. Determining whether an RF cavity with an unannounced gradient or phase transient is the culprit would be a valuable tool for operations staff in addressing recurring beam loss incidents. A prototype offline system was developed in the fall of 2022, utilizing a dispersive beam position monitor (BPM)...
During the Long Shutdown 2 (LS2 2019-2021) of the LHC, the orbit feedback correction software (OFB) of the LHC was redesigned to satisfy new requirements for LHC Run 3 (2022-2025) and to clean up legacy functionalities. The OFB is an essential component of LHC high intensity operation since the orbit must be stabilized to a fraction of the beam size during the entire LHC machine cycle....
SIRIUS is a 4th generation synchrotron light source built and operated by the Brazilian Synchrotron Light Laboratory (LNLS). Recently, investigations of noise sources and the storage ring RF plant identification enabled a fine-tuning of the Digital Low-Level Radio Frequency (DLLRF) parameters. This paper presents the main improvements implemented, which include the mitigation of 60Hz noise...
The institute of applied physics (IAP), university of Frankfurt, has been working for years on the development of increasingly powerful 4-Rod RFQ accelerators for hadron acceleration. The need for such accelerators has increased significantly in the recent past, as accelerator-driven neutron sources are becoming increasingly important following the closure of various test reactors. High beam...
The design and manufacturing of the Nonlinear Injection Kicker is one of the upgrade project for the Taiwan Photon Source (TPS). In accordance with the requirements of the developed ceramic vacuum chamber, it is necessary to apply a uniform titanium coating on the inner surface of the ceramic substrate to reduce the impedance and image current observed by the stored electron beam. Therefore,...
The National Synchrotron Radiation Research Center houses two accelerators, namely the Taiwan Light Source and the Taiwan Photon Source. It also includes approxi-mately 40 end stations.
The center has an information display board system that integrates information from the Instrumentation and Control Group, Experimental Facilities Division, Scien-tific Research Division, Radiation and...
During the LHC Intensity Upgrade (LIU) implementation, it became evident that an injector de-cabling project was needed to increase infrastructure resilience. Several difficulties in the setup of the project, originating from the 50 years history of some of the machines concerned, enforced the need of a meticulous and careful step-by-step approach to structure the project and defined its...
Following the study progress on the FCC-ee radiofrequency systems (i.e. length of the cryomodules), general services infrastructure (i.e. electrical, cooling, ventilation), transport and handling volumes, and alignment requirements, the 3D integration evolved with a new configuration scenario. This paper describes the new proposal to locate the collider RF elements (400 MHz and 800 MHz...
The SIS100 heavy ion synchrotron is the central machine of the FAIR (Facility for Antiprotons and Ions Research) project at GSI. It presents complex challenges due to its features handling high-intensity ion beams from protons up to uranium. It demands sensitive beam diagnostics with robust Machine Protection Systems (MPS). Due to anticipated extreme conditions, one safety subsystem includes...
We present simulations compared to an experiment based on Derbenev’s flat-to-round (FTR) transformation designed to match an electron beam from a high energy storage ring into a solenoidal cooling channel. Our experiment transports a large-aspect-ratio electron beam through a skew quadrupole system and a long solenoid. We focus on examining the complex dynamics of FTR systems in low-energy...
The temporal characteristics of ultra-high dose rate beams delivered for FLASH research are often dictated by machine constraints, making it challenging to compare the outcomes across studies performed at different facilities. To broaden the opportunities for systematic, non-clinical FLASH research, this study explores methods to deliver beams with customizable time structures from a medical...
Digital Tomosynthesis (DT) is a 3D mode of x-ray imaging. Adaptix Ltd have developed a novel mobile DT device enabled by implementing an array of R-ray emission points and a flat-panel detector. This device gives access to human and animal 3D imaging, as well as to non-destructive material evaluation. DT is not as clinically popular as Computed Tomography (CT) or radiography, and flat-panel...
MedAustron is a state-of-the-art synchrotron-based accelerator complex that provides irradiation with proton and carbon ion beams. The implemented DCCT feedback based control of the current provides good results for magnets of the accelerator in terms of precision and accuracy. However, since the B-Field of the main ring dipoles is not directly controlled, parasitic, time consuming effects...
Current superconducting radio frequency (SRF) cavities are predominantly constructed from high purity niobium which is pushed to its theoretical limit. To enhance future cavity performance by minimizing operational power losses and increasing accelerating field strength, the focus of research must shift to alternative cavity materials. An effective strategy involves depositing superconducting...
The transverse narrow-band impedance makes a major contribution to the transverse coupled-bunch instability, which may deteriorate the beam quality in multi-bunch, high-intensity circular accelerators. Thus, strict restriction on the transverse narrow-band impedance are implemented during the initial accelerator design phase. However, slight component structure deviations during the...
Electromagnetic choppers are a critical subsystem that slices particles at specific intervals and precisely directs them to a target or experiment. This simulation study was carried out to determine the correct operating parameters of the Electromagnetic Chopper, optimize it and increase its overall performance. At the same time, beam dynamics simulations aim to model in detail the movement of...
The Linac Coherent Light Source II (LCLS-II) at the SLAC National Accelerator Laboratory represents a groundbreaking advancement in the realm of Free Electron X-Ray Laser (XFEL) science. This 1.3 GHz continuous-wave superconducting RF LINAC is designed to generate 4 GeV electron bunches up to one MHz, propelling the capabilities of XFEL sources. Achieving a significant milestone, the LCLS-II...
In the architecture of the protection of the superconducting magnets of the Large Hadron Collider (LHC), systems such as Quench Heater Discharge Power Supplies (HDS), Local Protection Interface Module (LIM), Linear Redundant Power Supplies (LPR), and Power Packs (LPUS) are crucial. Thousands of these devices, some in operation since 2007, directly impact LHC’s availability and...
The SSRF storage ring has been upgraded to an asymmetric lattice containing two super-bend cells, two double-mini-βy optics (DMB) cells and a superconducting wiggler (SCW) in 2019. Due to the destruction in structural symmetry, the restoration of linear optics becomes an essential issue in commissioning and routine beam dynamics maintenance. During the initial commissioning, the linear optics...
This study focuses on developing beam-matching optics for the transport of the MITHRA beam into plasma to study long range plasma effects. To ensure successful injection into the plasma chamber, matching conditions are crucial at the entrance. A dedicated focusing system, comprising beam-matching optics, is designed to transport the beam from the 1.5-meter linear accelerator (linac) and align...
The LCLS-II is a high repetition rate upgrade to the Linac Coherent Light Source (LCLS). The emittance and dark current are both critical parameters to optimize for ideal system performance. Here we summarize the role these tools played in the commissioning period and are playing in the current operational stage of the LCLS-II injector, which provides an example of how other accelerator...
In the context of LATINO (Laboratory in Advanced Technologies for INnOvation) and Rome Technopole Projects founded by Regione Lazio and NextGenerationEu, and directly involved in the EuPRAXIA@SPARC_Lab flagship project, a testing facility for X-band (TEX) has been established at the Frascati National Laboratories of INFN. TEX is dedicated to the examination of radiofrequency X/C-band, aiming...
Integrable systems possess a hidden symmetry associated with the existence of conserved quantities known as integrals of motion. These systems play an important role in understanding general dynamics in accelerators and have potential for future designs. This work will cover two automated methods for finding integrable symplectic maps of the plane. The first algorithm is based on the...
Skeleton cyclotron is a compact size air-cored cyclotron with a high temperature superconducting (HTS) coil system. HTS coils’ high critical current density and high heat stability allow magnetic field induction without using any iron core. With this advantage, the magnetic field configuration can be adjusted quickly without consideration for the hysteresis from iron. The purpose of skeleton...
In the framework of the acceleration techniques, the Plasma Wake Field Acceleration (PWFA) is one of the most promising in terms of high machine compactness. For this purpose, a crucial role is played by the particle beam focusing upward and downward the plasma-beam interaction, performed by high gradient Permanent Magnet Quadrupoles (PMQs). In the framework of the INFN-LNF SPARC_LAB (Sources...
One of the most promising advantages of nonlinear integrable optics is strong amplitude dependent tune shift without degrading the dynamic aperture. The integrable optics test accelerator (IOTA) at Fermilab is constructed around nonlinear lattice elements of the elliptical type as described by Danilov and Nagaitsev. Detuning and dynamic aperture scans in IOTA were performed using a fast dipole...
The Taiwan Photon Source (TPS) BL-02A beamline at the National Synchrotron Radiation Research Center is a curved magnet beamline designed for white light mi-crotomography experiments, wherein biological samples are irradiated with high-energy white light for structural analysis. Experimenters frequently complain of odors when entering the end-station Hutch to change samples, which may be...
The Quarter Wave Resonator (QWR) is a longitudinal bunching cavity for the MEBT section of the Pre-injector Upgrade project at ISIS. Four cavities are required with at least one functional spare. The production of a full scale prototype is discussed here. Three main manufacturing challenges were encountered as follows: the tight manufacturing tolerances of the stainless steel tank, most...
This paper describes the mechanical design of the Future Circular Collider e+e- interaction region. The Future Circular Collider, as a forefront particle accelerator project, demands meticulous attention to the mechanical integrity and performance of its components, to the integration of the different systems and to the respect of the spatial constraint. The vacuum chamber design, the support...
Radiation therapy is an important oncological treatment method in which the tumor is irradiated with ionizing radiation. In recent years, the study of the beneficial effects of short intense radiation pulses (FLASH effect) or spatially fractionated radiation (MicroBeam/MiniBeam) have become an important research field. Systematic studies of this type often require research accelerators that...
The European Synchrotron Radiation Facility (ESRF) presently operates with the Hybrid Multi-Bend Achromat (HMBA) lattice that features 𝛽-functions of 6.9 m and 2.7 m in the horizontal and vertical planes at the center of the straight sections. New optics were designed to increase the brilliance of beam lines with a single undulator placed at the center of the straight section. The reduction...
Space charge has been a limiting effect for low energy accelerators inducing emittance growth and tune spread. Tune shift and tune spread parameters are important for avoiding resonances, which limits intensity of the beam. Circular modes are round beams with intrinsic flatness that are generated through strong coupling, where intrinsic flatness can be transformed to real plane flatness...
The beam wire scanners of the CERN Super Proton Synchrotron (SPS) experienced multiple failures of their carbon wires caused by the high-intensity beam during a very short period in April 2023. Different modifications of the existing instrument were therefore studied to reduce the beam-induced power without compromising its functionality nor negatively affecting the beam coupling impedance....
The Dual-Axis Radiographic Hydrodynamic Test Facility (DARHT) uses a spinning wheel debris blocker as a crucial machine protection system to prevent target debris from the electron to X-ray conversion process from traveling upstream and damaging the accelerator. The spinning wheel in use on DARHT Axis-I consists of two spinning disks normal to the beamline, each with an open slit that crosses...
This paper presents a study on the upgrade and modernization of the magnet power supplies of the KARA (Karlsruhe Research Accelerator) storage ring. The existing power supplies, which have been in operation for more than two decades, were facing obsolescence and operational limitations. To ensure the continued availability and reliability of the facility for the next decade and beyond, a...
The Los Alamos Neutron Science Center (LANSCE) accelerator uses charge exchange injection to accumulate a high-intensity proton beam in the Proton Storage Ring (PSR). H- ions are accelerated to 800 MeV and then stripped of their electrons by a thin foil at the ring injection site. The Monte Carlo N-Particle (MCNP) radiation transport code has been used to estimate the effect foil thickness has...
Exploring the fundamental properties of materials such as niobium, NbTiN, multilayers or Nb3Sn, in high-precision surface resistance measurements is highly relevant to superconducting radio-frequency (RF) technology. Typically, for a precise determination of the RF properties of superconducting samples, the calorimetric measurement is carried out with a quadrupole resonator (QPR). Still, one...
The High Energy Photon Source (HEPS) is a fourth-generation synchrotron radiation facility with design beam emittance of less than 60 pm. Impedance modelling is an important subject due to the adopted small beam pipe as well as the tight requirements from beam collective effects. Narrowband impedances can be generated by the discontinuity of the vacuum chamber or the finite conductivity of the...
In 2016 the Australian Synchrotron embarked on the BRIGHT program to build four new insertion device beamlines: Biological Small Angle X-ray Scattering (BioSAX), High Performance Macromolecular Crystallography, Advanced Diffraction and Scattering and Nanoprobe beamlines. To maximize the flux for these very demanding beamlines, cryogenic and short period devices have been selected. In...
The TPS (Taiwan Photon Source) is a third generation 3 GeV synchrotron light source. Some beamlines use synchrotron pulses in conjunction with laser pulses for pump-probe experiments, which is a time-resolved experiment method for capturing the temporal evolution of the pumped process. Periodic X-ray pulses are provided by the synchrotron light source as detecting light (Probe), and laser...
An increasing number of accelerators are pursuing FLASH radiotherapy, which promises to mitigate unwanted damage to healthy tissues by applying ultra-high dose rates. To reach this extreme intensity regime, it is necessary to maximize the transmission through the exit nozzle, apart from increasing the accelerator’s output beam current. Simultaneously, the delivered beam properties must satisfy...
It has been seven years since the Taiwan Photon Source (TPS) started to serve users in 2016. Sixteen beamlines had been installed in the first and second phases of TPS beamline project. The third phase project was also launched in 2021. Considering the experimental hall is more compact and power saving issue, our research aimed to analyze a modified air conditioning system with better cooling...
At the Facility for Rare Isotope Beams (FRIB) Advanced Rare Isotope Separator (ARIS), wedges are critical devices to achieve rare isotope beam production. Different ions experience a different amount of slowing down by the wedges, which leads to a spatial separation of ion species and enables separation/purification of the secondary isotope beam.
As of December 2023, wedge systems have...
The BESSY II Booster has been reliably delivering beam to the storage ring for several decades. As part of an effort to better understand and control beam dynamics in the Booster, new instrumentation, including Libera Spark ERXR beam position processors, has recently been installed and commissioned. These instrumentation upgrades have enabled measurements and corrections of optics parameters...
The design of a helium synchrotron for cancer therapy is being studied and optimized in the context of the Next Ion Medical Machine Study (NIMMS) at CERN. In particular, the effects of combined-function magnets and their geometry on the optics functions and hence on the beam size are evaluated. Moreover, the introduction of defocusing quadrupoles in the lattice is investigated as a means of...
Ultrafast electron diffraction (UED) is a growing accelerator application that enables the study of transient material processes at sub-picosecond timescales with nanometer spatial resolution. In this proceeding, we present simulations of the Cryogenic Brightness-Optimized Radiofrequency Gun (CYBORG) beamline using the General Particle Tracer (GPT) code that are optimized for the application...
Synchrotron light source storage rings aim to maintain a continuous beam current without observable beam motion during injection. One element that paves the way to this target is the non-linear kicker (NLK). The field distribution it generates poses challenges for optimizing the topping-up operation. Within this study, a reinforcement learning agent was developed and trained to optimize the...
Proton therapy has a significant advantage over conventional radiation therapy. Yet most hospitals do not offer it because of the significant cost associated with it. In this work, we developed the most compact, low-cost, expandable, and high-performance beamline for multi-room particle therapy. The accelerator is located at a lower level (underground) and the beamline guides the particles to...
A method to simultaneously determine the magnetic centers of multiple magnets with beam-based measurements is proposed. Similar to the quadrupole modulation system (QMS) method that is widely used for beam-based alignment measurement, the strengths of the group of selected magnets are modulated. The orbit shifts induced by the modulation are used to deduce the kicks applied at the magnet...
The features of particle radiation in two-layer and three-layer cylindrical waveguides are studied in the presence of a frequency dependence of conductivity in metal layers and dielectric and magnetic permeability in dielectric layers. A comparison is made with the results obtained at constant values of the electromagnetic parameters of the layers.
Within the LHC Injectors Upgrade (LIU) project, the LHC injectors received major upgrades that resulted in an unprecedented brightness performance. In the framework of the Physics Beyond Colliders (PBC) study, the full potential of the upgraded injectors is being explored for the improvement of the Fixed Target (FT) beams as well. This contribution details the recent studies on the beam...
Generating beam with nC-level charge is of great significance for particle colliders. In order to achieve lower emittance and length of bunch, based on the photocathode injector, we designed a L-band gun and L-band accelerating tube. However, with many coupled parameters, it is difficult to optimize its performance to the limit when optimizing them separately. Therefore, we employed a...
As the FFA@CEBAF energy upgrade study progresses, it is important to investigate the impact of radiation exposure on the permanent magnet materials to be used in the upgraded fixed field alternating gradient (FFA) arcs. To address this, Jefferson Lab has awarded a Laboratory Directed Research and Development (LDRD) grant to study the resiliency of several permanent magnet materials placed in a...
This paper reports the exploratory studies on advanced accelerator technologies performed within the I.FAST (Innovation Fostering in Accelerator Science and Technology) EU project, and in particular the key results of the additive manufacturing Task 10.2 – “Additive Manufacturing – applications and potential developments” and Task 10.3 – “Repair of damaged accelerator components by AM...
Designed as an internal tool at CERN, PLAN has a pivotal role in the centralization and macroscopic aggregation of technical intervention and enhancement activities planned within the accelerator complex. As part of a broader strategy to enhance tool utilization and extract valuable insights, a substantial endeavor during RUN3 aimed to develop and disseminate analytics derived from...
The Facility for Rare Isotopes Beams started operation nearly two years ago and ramped up beam power by a factor of 10 from 1 kW to 10 kW. The main contributions to the beam losses are due to the beam halo generated in the ion source and low energy beam transport, the effect of the stripper, and multiple charge state acceleration. The linac tuning procedure includes setting both RF cavity...
The electrostatic chopper for the new ISIS MEBT is a fast deflecting device which will create gaps in the beam coming out of the RFQ, which will improve the trapping efficiency when injecting the beam into the ISIS synchrotron. The fundamental design (including electromagnetic and thermal calculations, and sensitivity studies) are presented elsewhere. The practical aspects of the mechanical...
The APS Upgrade (APS-U) multi-bend acromat storage ring requires 1000 high-stability unipolar magnet power supplies. A precision current measurement and calibration system has been developed to independently measure the power supply output current to ensure the accuracy and repeatability of the supplies. The measurement system uses custom commercial DCCT current transducers along with...
The Institute for Applied Physics (IAP) installed a permanent test setup for up to \SI{60}{\kilo\watt} of RF power in cw mode for conditioning. The goal is to establish a time efficient test procedure for the future MYRRHA CH-cavities. Three test stands were designed to accommodate up to three cavities simultaneously.
All stations are curently tested via the \SI{175}{\mega\hertz} MAX RFQ...
The low emittance ( 4th generation) light source Elettra 2.0, that will replace Elettra the 3rd generation light source in Trieste Italy, will be commissioned in 2026. However the injector complex will be conserved but improvements will be done in order to be ready before of the storage ring commissioning. Optics modification, hardware upgrade and software development will be undertaken to...
The LBNF Absorber consists of thirteen 6061-T6 aluminum core blocks. The core blocks are water cooled with de-ionized (DI) water which becomes radioactive during beam operations. The cooling water flows through gun-drilled channels in the core blocks. The cooling water is supplied by the LBNF Absorber Radioactive Water (RAW) cooling system which is designed as per ASME B31.3 Normal Fluid...
Ultrafast high-energy pulsed electron beams can provide deep penetration and variable linear energy transfers for testing microelectronics for radiation-induced single-event effects. Early experiments at the UCLA PEGASUS beamline (3 MeV) with 1 ps electron bunches and a 50 $\mu$m spot size yielded charge collection transients that are compared with reference heavy ion data. Sub-micron focusing...
We are commissioning a 2.5~MeV proton beam for the Integrable Optics Test Accelerator at Fermilab, allowing experiments in the strong space-charge regime with incoherent betatron tune shifts nearing 0.5. Accurate modelling of space-charge dynamics is vital for understanding planned experiments. We compare anticipated emittance growth and beam loss in the bare IOTA configuration using...
The proton beam power limit for a solid-tungsten spallation target is largely determined by beam induced thermomechanical structural loads and decay heat power deposition, while its lifetime is limited by radiation damage and fatigue life of the target materials. In this paper, we studied the power limits of a stationary water-cooled solid tungsten target concept. Tantalum clad tungsten was...
At the tandem ion accelerator laboratory of the Jožef Stefan Institute (JSI) in Ljubljana, Slovenia we are developing a control system for the Low Energy Branch (LEB) ion beamline. This activity is ongoing simultaneously with the hardware construction of the ion beamline branch dedicated to the research with low-energy ion beams with energies up to 30 keV.
The LEB instrumentation is...
S-band deflectors are generally operated on pulsed mode for beam diagnosis. We plan to deploy 5 S-band (2997 MHz) deflectors to accurately measure the longitudinal time distribution of ultra-short electron beam pulses in Shenzhen Superconducting Soft X-ray Free Electron Laser (S3FEL). A microwave system of one deflector consists of a low-level RF system (LLRF), a solid-state amplifier,...
Beam motion during injections could be a serious problem to x-ray users and jeopardize their experiments. In the Cornell Electron Storage Ring (CESR) the particles are injected with pulsed elements such as pulsed bumpers and septum which could cause transient motion of the stored beam. By analyzing the turn-by-turn position data of the stored beam acquired during injection, we identify the...
LHC injection kickers (MKI) are pulsed at high voltage to achieve magnetic field pulses with fast rise time. The MKIs contain a beam screen to help shield their ferrite yoke from beam induced heating. However, additional means of mitigating beam induced heating, for the high luminosity LHC (HL-LHC) era, are required. To achieve this, the MKIs are sequentially being upgraded to low impedance...
The compact storage ring project for accelerator research and technology (cSTART) is realized at the Institute for Beam Physics and Technology (IBPT) of the Karlsruhe Institute of Technology (KIT). Flexible lattice of a ring benefits variety of operation modes. Different physical experiments are planned at cSTART. In particular, deep variation of momentum compaction factor with simultaneous...
In late 2023, Thomas Jefferson National Accelerator Facility (Jefferson Lab) funded a Laboratory Directed Research and Development (LDRD) grant dedicated to investigating the impact of radiation on permanent magnet materials. This research initiative is specifically geared towards assessing materials slated for use in the CEBAF energy upgrade. The experimental approach involves strategically...
A prototype Beam Gas Curtain (BGC) monitor was installed at the Large Hadron Collider (LHC) at CERN to provide 2D images of the transverse beam profile during the ongoing Run 3 (2022 to date) and in view of the High Luminosity LHC upgrade (HL-LHC). By design, the BGC operation generates collisions between the beam particles and an injected gas jet proportionally to the beam intensity and the...
The 2023 operation of the Large Hadron Collider (LHC) at CERN included a one-month-long run with fully stripped Pb ion beams, marking the first heavy-ion run since 2018, and delivering Pb ion collisions at an unprecedented center-of-mass energy of 5.36 TeV per nucleon pair. During this period, the radiation fields in the LHC tunnel have been measured by means of different radiation monitors,...
Data acquisition (DAQ) is an ubiquitous feature in modern particle accelerator measurement and control systems. At the Paul Scherrer Institut (PSI), a next generation of electronic devices is being designed to meet the demands of upcoming renewal of facilities. The new developments utilize the CompactPCI Serial (CPCI-S.0) platform, and will cover a diverse set of applications, including Low...
Nowadays, the real-time control is more and more popular in the particle accelerator field because it is a powerful tool for stable operation and beam loss suppression in the particle accelerator. However, in the Japan Proton Accelerator Research Complex (J-PARC) Main Ring (MR), real-time control has not been widely used in magnet power supplies yet. Magnet power supplies are very easily...
During the last long shutdown of the accelerators at CERN (LS2), the main radio frequency system of the Proton Synchrotron Booster (PSB) was upgraded. A wideband
system with Finemet magnetic alloy cavities driven by solid-state amplifiers replaced several different ferrite-loaded cavities. In measurements post-LS2, the longitudinal beam stability did not match predictions, which triggered a...
Neptunium-236g is a rare radionuclide used for nuclear material analyses. The availability of 236gNp is limited and the viable production routes are costly, time consuming, and only produce trace quantities of the desired product. For this work, two known production methods were tested to determine product recovery, purity, and viability for use as a tracer. The first method utilizes a...
The stretched-wire alignment technique is one method of magnet alignment for linear induction accelerators. The applications of the Stretched-Wire Alignment Technique (SWAT) have been implemented for aligning magnets/solenoids on the Scorpius linear induction accelerator which will be sited at the Nevada National Security Site and the Flash X-Ray (FXR) linear induction accelerator at Lawrence...
We describe how the Mu*STAR system uses a superconducting proton accelerator produces a proton beam powerful enough to drive several subcritical small modular reactors (SMRs). Each SMR is a graphite-moderated molten salt (MS) fueled reactor with an internal spallation target to generate source neutrons. These source neutrons initiate fission chains that die out, producing energy in a...
The standard fabrication method for superconducting cavities is to press high RRR niobium sheets to form half cells, which are then joined by EBW (electron beam welding) to form cavities. If the anisotropy of the niobium sheet is too large, gaps will form when the half-cells are joined, so a sheet with low anisotropy is required. To reduce the anisotropy of the sheet, it is essential to apply...
To enhance the intensity of X-ray emission through bremsstrahlung radiation, a light source was designed based on an electron cyclotron and a compact electron storage ring. The compact structure and limited space posed challenges to the injection system. In this paper, we introduce the key component, the "perturbator," along with its matching pulse power supply. These were de-signed based on...
Hefei Light Source (HLS) is the first dedicated synchrotron radiation facility in China. HLS-II operates in the TOP-OFF constant-current mode. For the safety of personnel, it is crucial to analyze the radiation fields applying Monte Carlo. The radiation source directly affects the results. The paper discusses the impact of three radiation source models on the radiation field results. In the...
Ultra-high energy electrons (UHEE) are used to investigate their effect on tumor cells and healthy tissue in short pulses of microseconds at the electron accelerator facility ELSA. This may enable highly efficient treatment of deep-seated tumors due to the FLASH effect. In a preliminary setting electrons with an energy of 1.2 GeV are used to irradiate cell samples which are located inside a...
Thomas Jefferson National Accelerator Facility (Jefferson Lab) currently studies the feasibility of upgrading its energy to 22GeV. It considers addition of six more linac passes. The highest energy passes will share two new arcs designed using the Fixed-Field Alternating Gradient (FFA) technology. The FFA arcs are built using permanent combined-function magnets. They will be connected to the...
The following paper embarks on an in-depth exploration of extraction kickers employed at some of the most renowned particle physics and neutron science facilities worldwide. Specifically, we delve into the extraction kickers utilized at the Spallation Neutron Source, Fermi National Accelerator Laboratory, Los Alamos Neutron Science Center, and delve into the novel inductive adder structures....
The normal-conducting injector of the superconducting proton linac of the European Spallation Source (ESS) was commissioned in 2023. Commissioning of the superconducting linac is planned by end of 2024, followed by first beam on the spallation target in 2025. One of the prominent challenges in commissioning and operation of high power accelerators, such as the linac of the ESS, is to minimize...
At Los Alamos National Laboratory (LANL), we developed a 1.6-cell C-band RF photoinjector for the Cathodes And Radiofrequency Interactions in Extremes (CARIE) project. The injector will be used to study the behavior of advanced photocathode materials under very high RF gradients. The photocathodes will be prepared with an INFN-style photocathode plug, compatible with the plugs used by other...
Additive manufacturing ("AM") has become a powerful tool for rapid prototyping and manufacturing of complex geometries. A 433 MHz IH-DTL cavity has been constructed to act as a proof of concept for direct additive manufacturing of linac components. In this case, the internal drift tube structure has been produced from 1.4404 stainless steel, as well as pure copper using AM. We present the most...
FLASH Therapy, an innovative cancer treatment, minimizes radiation damage to healthy tissue while maintaining the same efficacy in tumor cure as conventional radiotherapy. Successful integration of FLASH therapy into clinical practice, specifically for treating deep-seated tumors with electrons, relies on achieving Very High Electron Energy (VHEE) within the 50-150 MeV range.
In collaboration...
The Proton Improvement Plan-II Injector Test (PIP2IT) Facility had been fully constructed and commissioned at Fermilab during 2020-21. The PIP2IT beamline includes a H- ion source capable of delivering 15 mA, 30 keV DC or pulsed beam, a Low Energy Beam Transport (LEBT), a 162.5 MHz,continuous wave (CW) Radio Frequency Quadrupole (RFQ) that accelerates the beam to 2.1 MeV, a 10-m Medium Energy...
Even though the strengths are weaker, different from quadrupole offsets, sextupole offsets are causing more complicated disturbances on the storage ring optics. They are making orbit distortion and quadrupole kicks as well as couplings. The offsets in chromatic sextupoles can affect the correction of chromaticity too. The closed orbit corrections in modern storage rings are fast and reliable,...
We discuss the result of calculation and measurement of the transverse kick in the SLAC accelerating section in a single bunch and multi-bunch regimes. We present a simple estimate, which can be used in practical situations.
The beam loading effect results in a gradient reduction of the accelerating structures due to the excitation of the fundamental mode when the beam travels through the cavity. A recent implementation of this process in the tracking code RF-Track allows the simulation of realistic scenarios, thus revealing the impact of this phenomenon in start-to-end accelerator designs. In this paper, we...
The RUEDI (Relativistic Ultrafast Electron Diffraction & Imaging) ultrafast electron diffraction (UED) beamline aims to provide electron bunches to diffraction samples with an at-sample temporal resolution of sub-10 fs. Electron bunches of such short duration prove non-trivial to measure at electron beam kinetic energies of 4 MeV. A diagnostic beamline design is presented to enable...
The Los Alamos Neutron Science Center (LANSCE) accelerator delivers high intensity proton beams for fundamental science and national security experiments since 1972. The Proton Storage Ring (PSR) accumulates a full 625-us macro-pulse of proton beam and compresses it into a 290-ns long pulse, delivering an intense beam pulse to the Lujan Neutron Science target. The proposed LANSCE Modernization...
Crab crossing in the Electron-Ion Collider (EIC) is planned to provide head-on beam collisions and maximize luminosity for beams with a 25 mrad crossing angle. This crab crossing requires superconducting RF crab cavities for both EIC electron and hadron beams. Phase and amplitude errors of these transverse crab cavities can cause emittance growth, of particular concern for hadron beams and the...
On-axis injection mode is planned to use in the Southern Advanced Photon Source (SAPS), which requires high quality to injection pulsed power supply. Gyromagnetic nonlinear transmission line (GNLTL) is introduced as a pulse compressor to meet the needs for pulse width. In this paper, 3-D finite element model is established based on Landau-Lifshitz-Gilbert equation and Maxwell’s equations. The...
We present the 100 MeV injector design for the LANSCE Accelerator Facility, which is designed to replace the existing 750-keV Cockcroft-Walton-columns-based injector. This new Front End includes two independent low-energy transports for H+ and H- beams merging at the entrance of a single RFQ, with the subsequent acceleration of particles in the new Drift Tube Linac. The challenge of this...
For the injection into the SOLEIL II storage ring a beam with small transverse and longitudinal sizes is necessary, which requires the booster synchrotron to be upgraded. The new booster is designed as a multi-bend 16BA Higher-Order Achromat lattice with a small emittance of 5 nm∙rad at 2.75 GeV. Robustness of the lattice has been studied with realistic errors in magnet alignment and...
Current transmission electron microscopes (TEM) accelerate electrons to 200-300 keV using DC electron guns with a nanoamp of current and very low emittance. However at higher voltages these DC sources rapidly grow in size, oftentimes several meters tall for 1 MeV microscopes. Replacing these electron guns with a compact linac powered by solid-state sources could dramatically lower cost while...
In a circular collider, precise control of the linear optics in the vicinity of the interaction points plays a crucial role in ensuring optimal operational performance and satisfying the machine protection constraints. Superconducting magnets are affected by unavoidable field errors that impact machine performance, and mitigation strategies are usually put in place to improve the situation....
The upcoming Proton Improvement Plan-II (PIP-II), designated for enhancements to the Fermilab accelerator complex, features a Beam Transfer Line (BTL) that channels the beam from the linac exit to the booster. In the absence of longitudinal focusing beyond the superconducting linac, the beam experiences an elevated momentum spread, primarily due to nonlinear space-charge forces, surpassing the...
The SSRF (Shanghai Synchrotron Radiation Facility) superconducting wiggler consists of three parts: a superconducting multipole magnet, a cryostat system and magnet power & control system. Superconducting multipole magnets can generate a strong magnetic field with a peak of 4.2 T, and the generated magnetic field alternates positively and negatively along the direction of electron motion in...
The installation of the STAR High-Energy Linac, the energy upgrade of the Southern European Thomson Back-Scattering Source for Applied Research (STAR) project at the University of Calabria, was conducted by INFN by the end of 2023. This paper presents the testing procedures aimed at confirming the consistency, completeness, and quality of the STAR accelerator upgrade installation (electron...
The Los Alamos Neutron Science Center (LANSCE) accelerator delivers high intensity proton beams for fundamental science and national security applications since 1972. LANSCE is capable of simultaneous H+ and H- beam operations to multiple experiments requiring different time structures. This is achieved upstream in the facility with a combination of two 750 kV Cockcroft-Walton (CW) generators,...
Tokyo Denkai has been producing niobium for superconducting cavities since 1985. We have also produced niobium for L-band cavities since the beginning of their development, and have a large number of production records. In particular, more than 20,000 pieces have been delivered to TESLA based on the XFEL-007 specifications for the European XFEL, LCLS-II, LCLS-II HE, and SHINE projects. In this...
During past 7 years at Varex Imaging Corporation, we have created a pilot production line for Accelerator Beam Centerlines (ABC), replacing supply of Beam Centerlines (BCL) by Varian after the Component Division separated from Varian in 2017, becoming an independent public company. Our ABC production growth rate seems to double every year, and in last quarter of 2023 Fiscal Year, we delivered...
Optimizing the configuration of an operational cycle of a collider such as the LHC is a complex process, requiring various simulation studies. In particular, Dynamic Aperture (DA) simulations, based on particle tracking, serve as indispensable tools for achieving this goal. In the framework of the high-luminosity LHC (HL-LHC) studies, our primary focus lies in performing parametric beam-beam...
Due to the constrains imposed by the tight geometry of the ALBA storage ring, the initial 6BA lattice envisioned for the ALBA-II upgrade was reconsidered in favor of a more relaxed 5BA configuration. The first engineering studies of magnets and vacuum chambers made evident many short comings of the 6BA optics. The here proposed 5BA optics allows for an easier integration at cost of a small...
The Bonn Isochronous Cyclotron provides proton, deuteron, alpha and other light ion beams with a charge-to-mass ratio Q/A >= 1/2 and kinetic energies ranging from 7 to 14 MeV per nucleon. The beam is guided through a high-energy beam line (HEBL) to one of five experimental sites. The installation of the irradiation site for high-uniformity radiation hardness tests of Si detectors is now...
One of the crucial control systems of any synchrotron is the Low-Level Radio Frequency (LLRF). The main purpose of an LLRF is to generate and maintain a stable electric field within the accelerator cavities by controlling its amplitude and phase. SAFRAN Electronic & Defense Spain S.L.U. is currently developing the new digital LLRF to update the system in the ALBA Synchrotron Light facility...
The Spallation Neutron Source (SNS) Beam Test Facility (BTF) supports the study of beam dynamics in the front end of a high power LINAC. The BTF combines a replica of the SNS front end, including nearly-identical ion source, RFQ and MEBT, with extensive phase space diagnostics and a FODO transport line. Diagnostic capabilities include direct measurement of 6D phase space distribution and...
Transverse bunch-by-bunch (BxB) feedback system has been designed, fabricated, installed, and tested with beam at the Advanced Photon Source Upgrade (APS-U) storage ring. The transverse feedback system (TFB) is designed to suppress coupled bunch instabilities and single bunch instabilities. It adapted a stripline kicker design which has the same profile as the APS-U injection/extraction...
The SABINA project will add a user facility to SPARC_LAB at INFN in Frascati (Rome). For the THz line, an electron beam is transported to the APPLE-X undulators to produce photon pulses in the ps range, with energy of tens of µJ, with linear or elliptical polarization. Each undulator has four magnetic arrays that can be moved radially simultaneously to set the operating gap. Two arrays can...
Previous studies have identified turbulent mode coupling instability (TMCI) as one of the most severe single-bunch instabilities in the FCC-ee collider, potentially limiting its performance. Its threshold is influenced by both transverse and longitudinal wakefields arising from vacuum chamber resistive wall effects, discontinuities, and beam-beam interactions, the latter of which can be seen...
In order to enhance the accelerating gradient of accelerators, cryogenic accelerating structures have been investigated. Based on material characteristics and technical conditions, a fundamental design has been accomplished. Photonic band-gap (PBG) structures employ a lattice of rods to impede the propagation of RF field through the lattice at specific frequencies while effectively damping...
We describe experimental, theoretical, and simulation activities testing Derbenev’s 1998 proposal for using flat-to-round-to-flat (FTRTF) transformations to enable electron synchrotrons for ion beam cooling. FTRTF systems have also been proposed for storage-ring and single-pass light sources (FELs), beam sources, and microwave tubes. The experiment—based on a low-energy (5–10 keV) linear...
We study possibility of laser assisted charge exchange injection at the SNS. The realistic injection of LACE injection and accumulation into the Ring of SNS is considered. The design of stripping magnets at the injection area is one of the most challenging problems toward operational scheme of LACE at the SNS. Basic requirements and needed parameters of stripping magnets are studied. Based on...
To achieve very high luminosity, the next generation circular colliders adopt the crab waist collision scheme with a large Piwinski angle. In this scheme, beams collide with high current, low emittances, and small beta functions at the interaction point (IP). However, several effects arising from these extreme parameters, especially the coherent X-Z instability, will significantly impact the...
The LHC Injectors Upgrade project at CERN optimized the injection accelerator chain to deliver proton intensities per bunch of 2.3e+11 ppb. Throughout 2023, the LHC was filled with up to 2464 bunches per beam using a hybrid injection scheme, involving up to 236 bunches per injection, with a maximum intensity per bunch of 1.6e+11 ppb. These beam parameters already revealed significant beam...
Large grain niobium has a higher production yield than fine grain niobium, the price can be lowered. On the other hand, it has a significant reduction in mechanical strength. In this study, tensile tests were conducted on different RRR (RRR185 and RRR495) of large grain sliced discs and two tensile speeds (5 mm/min, 2 mm/min) with more than 50 samples under each condition. In general quality...
China Spallation Neutron Source (CSNS) is a large-scale scientific research facility located in Dongguan, China. It is a pulsed neutron source that uses a proton accelerator to produce neutrons, which are then used to study the structure and properties of materials at the atomic and molecular level. Since its opening, CSNS has steadily improved its operation efficiency and beam power year by...
The enormous potential of additive manufacturing (AM), in particular laser powder bed fusion (L-PBF), for the manufacturing of normal-conducting radio frequency cavities (cavities) has already been demonstrated. However, the required geometrical accuracy for GHz TM010 cavities is currently only achieved using: a) co-printed support structures, which are however difficult to remove for small...
The beam quality in terms of the transverse beam profiles from the CERN injectors plays a crucial role for the luminosity production at the LHC. Transverse tails beyond a Gaussian distribution have been observed in all the LHC injectors and efforts to optimize them are ongoing, as they can perturb operations due to large losses at LHC injection. At the CERN Proton Synchrotron (PS),...
Our research focuses on the design of a beamline. Due to the numerous beamline components involved, without strict optimization of each component's parameters, the transmitted temporal profile of beam may distort, failing to meet the expected requirements. Additionally, different initial temporal profile of the beam will undergo longitudinal shaping during transmission through the beamline....
Misalignment of magnets in the storage rings causes trajectory deviation when the beam traverses through magnets, resulting in the degraded performance of linear optics and nonlinear dynamics. The beam-based alignment (BBA) technique is commonly used to steer the beam passing through the centers of magnets. Recently, a new method has been developed to determine the centers of multiple magnets...
The Beam Interlock System (BIS) is the backbone of the machine protection system throughout the accelerator complex at CERN, from LINAC4 to the LHC. After 15 years of flawless operation, a new version of the BIS is currently being produced and will be installed in the LHC, SPS and North Area during CERN’s Long Shutdown 3, planned to start in 2026. Overall, more than 3,000 Printed Circuit...
Beam Plasma Interactions Experiment (Beam-PIE) is a NASA sounding rocket experiment that successfully ran in November 2023. Beam-PIE used space as a laboratory to explore wave generation from a modulated electron beam in the ionosphere. Beam-PIE electron accelerator used a 10keV electron gun and a 5-GHz RF cavity, enabling the acceleration of the electron beam to a total energy of ~25–60 keV....
The proton Electric Dipole Moment (pEDM) storage ring to measure the electric dipole moment of the proton [1] is proposed to be built in the tunnel of the Alternating Gradient Synchrotron (AGS) at Brookhaven National Laboratory (BNL) by storage ring EDM (srEDM) Collaboration. We proposed that the AGS Booster to pEDM ring transfer and injection line (BtP) would use the partial portions of the...
SLEGS is a Laser Compton Scattering gamma source. The gamma energy is 0.66 to 21.7 MeV, and the gamma flux is approximately 4.8e+5 to 1.5e+7 phs/s. Gamma activation method is used in beam flux monitor, medical isotpoe production and nuclear astrophysics in SLEGS*. Gamma beam flux under different collimated apertures has been checked by gamma activation method by using various half-life nuclide...
A new Machine Protection System (MPS) and the Beam Position Limits Detector (BPLD) system are being developed for APS Upgrade (APS-U) accelerator storage ring. The MPS/BPLD system consists of one main MPS and 20 local MPS/BPLD controllers distributed around the ring, each local controller is located on every odd double sector. Each LMPS handles one double sector. Each double sector can be...
LhARA, the Laser-hybrid Accelerator for Radiobiological Applications, is a proposed facility designed to advance radiobiological research by delivering high-intensity beams of protons and ions in unprecedented ways. Designed to serve the Ion Therapy Research Facility (ITRF), LhARA will be a two-stage facility that will employ laser-target acceleration in the first stage, generating proton...
The Linac Coherent Light Source II (LCLS-II) is a new addition to the SLAC accelerator complex. It is a 4 GeV, 120 kW superconducting Linac operating in continuous RF mode at 1.3 GHz with a beam repetition rate of up to 1 MHz. The prior generation of protection system beam loss monitors, whose operation is based on ion collection principles, are not suitable for operation in LCLS-II due to...
The IAP (Institute for Applied Physics) of the Goethe University Frankfurt has a long experience in the development of 4-Rod RFQs. In the course of a project funded by the HessenAgentur as part of LOEWE funding line 3, the basic design of the 4-rod RFQs is now to be further developed. The aim is to investigate whether an improvement in Q-Value and vacuum can be achieved through new production...
An advanced online monitoring system with dual systems is being developing for Hefei Advanced Light Facility (HALF). One is based on the C language, which integrates data acquisition, storage and interface display. The other is based on EPICS system, which developed Input/Output Controller (IOC) and Operator Interface (OPI) for data acquisition and display. The two systems are based on...
As a fourth-generation diffraction-limited light source, Hefei Advanced Light facility has high requirements on the alignment accuracy and installation efficiency of key components of the storage ring. We plan to use four laser trackers to build a high-precision pre-alignment system based on the principle of polygonal to achieve a pre-alignment accuracy of 30μm within the magnet unit...
A new proton CT(pCT) facility will be built in Shanghai Ruijin Hospital. The main structure of the proton CT includes a high gradient proton LINAC, a compact 360-degree gantry, and a proton imaging platform. In the proton LINAC, a 16 S-band proton accelerating tube increased the energy from 230 MeV to 350 MeV. To provide a more accurate and stable Radio-Frequency(RF) control, a CPCI-based...
The X-ray Imaging Laboratory is a radiation test facility developed by Rapiscan systems at their facility in Stoke-On-Trent, UK. The X-ray Imaging Laboratory comprises two areas: the Test Facility and the Linac Development Area. The Test Facility is a state-of-the-art facility designed for subsystem and system level testing of x-ray imaging hardware utilizing normal conducting electron linacs...
The Facility for Rare Isotope Beams (FRIB) is a high power heavy ion accelerator facility at Michigan State University completed in 2022. Its driver linac is designed to accelerate all stable ions to energies above 200 MeV/u with beam power of up to 400 kW. Currently FRIB is operating at 10 kW delivering various primary beams. The target absorbs roughly 25% of the primary beam power and the...
The thermal diffusion and acoustic properties of Nb impacts the thermal management of devices incorporating Nb thin films such as superconducting radiofrequency (SRF) cavities and superconducting high-speed electronic devices. The diffusion and acoustic properties of 200-800 nm thick Nb films deposited on Cu substrates were investigated using time-domain thermoreflectance (TDTR). The films...
The Facility for Rare Isotope Beams is a high power heavy ion accelerator completed in April 2022. The FRIB accelerator was commissioned with acceleration of heavy ions to energies above 200 MeV/nucleon (MeV/u) that collide onto a rotating single-disk graphite target. The remaining beam is absorbed by a water-cooled static beam dump that is oriented at a 6 degrees angle with respect to the...
We present initial results from the booster-to-storage-ring beam-loss monitor (BTSBLM) employing time-of-fight analysis to localize and minimize losses along the BTS line. The BTSBLM utilizes a pair of high-purity, fused silica fiber optic cables running in parallel along the 65-m BTS transport line. Photomultipliers located at both upstream and downsteam ends of each fiber monitor Cherenkov...
The precision of the proton therapy beam depends on maintaining high field quality in the magnet’s good field region. Iron yoke is employed in magnets to increase the magnetic field and reduce the fringe field. However, when providing a high magnetic field for transporting relatively high-energy particles, the saturation effect of the yoke can distort the field quality. To mitigate this...
In recent years, mixed helium and carbon ion irradiation schemes have been proposed to facilitate in-vivo range verification in ion beam therapy. Such a scheme proposes to deliver both ion species simultaneously, with the idea of performing the treatment with carbon ions, while exploiting helium for online dosimetry downstream of the patient.
The center for ion beam therapy and research...
Electronic logbooks contain valuable information about activities and events concerning their associated particle accelerator facilities. However, the highly technical nature of logbook entries can hinder their usability and automation. As natural language processing (NLP) continues advancing, it offers opportunities to address various challenges that logbooks present. This work explores...
The TPS is a latest generation high-brightness synchro-tron light source scheduled to be commissioned in 2014. Its booster is designed to ramp electron beams from 150 MeV to 3 GeV at a frequency of 3 Hz. There are 54 dipole magnets, powered by one power supply unit, and 84 quadrupole magnets, powered by 4 power supply units according to their respective functions. During routine user time, a...
The high gradient of the photocathode radio-frequency electron gun (RF gun) increases the potential for field emission from the metal surface. Consequently, emitted electrons escaping from the RF gun result in the generation of a dark current, thereby degrading the gun's performance. A thorough investigation into the dark current phenomenon within the accelerator structure plays a crucial role...
The paper outlines the successful implementation of a global tune feedback system at the Taiwan Photon Source (TPS) to compensate the tune variation resulting from adjustments in the gap and phase of the insertion devices. The global tune feedback system deployed in the TPS employs two families of quadrupole magnets to sustain betatron tunes at the desired working point. The adjustment...
Ionization scattering of electron beams with residual gas molecules causes ion trapping in electron rings, both in a collider and electron cooling system. These trapped ions may cause emittance growth, tune shift, halo formation, and coherent coupled bunch instabilities. In order to clear the ions and prevent them from accumulating turn after turn, the gaps in a temporal structure of the beam...
The conditioning of room temperature cavities is an exhausting process. To prevent damage to the cavity and auxiliary equipment, this potentially long process needs constant supervision or extensive safety precautions. Additionally, the unpredictability of every new conditioning makes the development of effective classical algorithms difficult. To reduce the workload for everyone involved and...
Measurements of the transverse beam halo in the Large Hadron Collider (LHC) provide crucial input for the performance evaluation of the collimation configuration in the High-Luminosity LHC (HL-LHC) era. Such measurements are carried out in various phases of the LHC operational cycle by scraping the beam with movable collimators. Understanding the halo population and halo formation mechanisms...
Impedance is a significant concern in modern storage rings like Diamond-II, due to instabilities limiting maximum bunch charge and other potential effects such as emittance dilution. Significant changes have been made to the Diamond-II impedance database, partly driven by progress in engineering design work, and partly by the requirements of particle tracking simulations and increase in...
The recent development of advanced black box optimization algorithms has promised order of magnitude improvements in optimization speed when solving accelerator physics problems. These algorithms have been implemented in the python package Xopt, which has been used to solve online and offline accelerator optimization problems at a wide number of facilities, including at SLAC, Argonne, BNL,...
This study presents a refined model of radio frequency (RF) systems by the transfer function perspective of the Pedersen model on the basis of microwave RLC circuit model. While the former concentrates on the signal variation or error analysis, focusing on the cavity-beam interaction. the latter emphasizes the signal's properties within the system, allowing for seamless integration with...
Hefei Infrared Free-Electron Laser device (IR-FEL) is a user experimental device dedicated to energy chemistry research that can generate high brightness mid/far infrared lasers. It is driven by an S-band linear accelerator with a maximum electron energy of 60 MeV. The stability of the final output laser is determined by the energy stability and spread of the electron beam, and the Low-Level...
Following the successful completion of the LHC Injectors Upgrade (LIU) project, since 2021 the Proton Synchrotron (PS) Booster has served the LHC injector chain with protons at an increased kinetic energy of 2 GeV. An upgrade of the ISOLDE (Isotope Separator On-Line DEvice) facility has long been considered to produce radioactive ion beams with a higher energy proton driver beam. A...
SPARC_LAB facility was born in 2004 as an R&D activity to develop a high brightness electron photo-injector dedicated to FEL experiments and exploration of advanced acceleration techniques. The electron source consists in a brazefree 1.6-cell S-band RF gun with a peak electric field of 120 MV/m and a metallic copper photocathode. The gun injects particles into two S-band sections, the initial...
Over the last 13 years, Muons has also worked with other companies (ADNA, Niowave) and institutions (Virginia Tech, Jefferson Lab, ORNL, INL, SRNL) on accelerator-driven subcritical reactors (ADSR), to take advantage of large advances in superconducting RF (SRF) accelerators. In the last decade, SRF proton accelerators have been demonstrated to have the power and efficiency to produce...
The Advanced Photon Source (APS) has recently installed and begun commissioning of a hybrid seven-bend-achromat design to replace the original storage ring. The APS Upgrade lattice includes two types of longitudinal-gradient dipoles, five types of transverse-gradient dipoles, and five types of high-strength quadrupoles. All of these magnets were designed** using three-dimensional magnetic...
Many accelerator control rooms rely on envelope models to simulate beam dynamics because they are fast and accurate at tracking the beam core. Particle-in-Cell (PIC) models, however, can track particles inside and outside the core and, with the improvements of computers, are now fast enough to be used in control rooms. The Spallation Neutron Source (SNS) at Oak Ridge National Laboratory is...
In contemporary radiotherapy, most accelerators employ the scatter technique to achieve a relatively uniform dose distribution of electron beams. However, this method often results in the loss of a substantial number of particles, leading to suboptimal efficiency. This paper proposes a method utilizing permanent magnet components to homogenize the beam, achieving both beam spreading and...
The slice model is the theoretical foundation for various beam-beam simulation methods. In the formulation of the slice model, some approximations have been made based on the assumption of particle beams with an extremely high Lorentz factor. However, this assumption might not always be valid for the particle colliders applied in the nuclear physics study because of the usage of heavy-ion...
Beam instrumentation is of critical importance for the operation and optimization of modern particle accelerators. With advancing accelerator technology and the increasing requirements for higher quality beams, it is an ever-present challenge that beam diagnostics must similarly progress. In this talk the instrumentation considered most impactful for the progress of 4th generation storage ring...
The superior superconducting properties of Nb3Sn promise enhanced RF performance (Q and Eacc) compared to Nb at any given temperature. The potential deployment of Nb3Sn-coated superconducting radiofrequency (SRF) cavities at 4 K, achieving performance comparable to Nb cavities at 2 K, signifies a transformative technology poised to enable innovative classes of SRF accelerators and improve the...
Overview on laser plasma accelerators since the dream beam results.
The world's smallest carbon ion treatment facility has been commissioned at Yamagata University. The treatment system consists of an ECR ion source, a linac cascade of 0.6 MeV/u RFQ and 4 MeV/u IH-DTL, a 430 MeV/u slow extraction synchrotron, and irradiation systems of a fixed horizontal beamline and a compact rotating gantry using superconducting combined function magnets. The size of the...
Superconducting radio frequency (SRF) cavities are the world’s most efficient engineered oscillators, and they have long been employed for extremely high efficiency transfer of energy to beams of charged particles. Decades of R&D for particle accelerators have led to modern treatments for SRF cavities that achieve higher performance than was previously possible. Advanced SRF cavities using...
An important upgrade programme is planned for the collimation system of Large Hadron Collider (LHC) for lead–ion beams that will already reach their high-luminosity target intensity upgrade in the LHC Run 3 (2022-2025). While certain effects like e-cloud, beam-beam, impedance, inject and dump protection are relaxed with ion beams, halo collimation becomes a challenge, as the conventional...
During last year a comprehensive R&D program on high-efficiency klystrons has been carried out in collaboration with industry. The first prototypes are being tested and experimental results are promising. The talk will describe the main results of this R&D focusing in the experimental ones.
The 4th generation synchrotron light sources and energy recovery linacs progress greatly in Japan. The first 4th generation synchrotron light source in Asia, NanoTerasu, has been constructed through a public-private regional partnership, whereas soon SPring-8 is to be upgraded. The energy recovery linac, which features not only high brightness but also sustainability as the cERL, and its...
In the US high energy planning process more than 30 colliders were considered. This talk gives an overview of these colliders and emphasized the strength of the various approaches.
