The SOLARIS storage ring, Poland’s first synchrotron light source, has marked a decade of successful operation, contributing significantly to scientific research and technological advancement. Commissioned in 2015 and inspired by the innovative design of Sweden’s MAX IV Laboratory, SOLARIS exemplifies the effectiveness of international collaboration in cutting-edge accelerator technologies....
The Electron-Ion Collider, which is currently being designed for construction at Brookhaven National Laboratory, will collide polarized electron beams (5-18 GeV) with polarized hadron beams (41-275 GeV) at luminosities up to 10^34 cm−2 s−1. The electron storage ring will contain about 750 dipoles. These dipoles must fulfill not only complex geometric constraints but also requirements set by...
Compared with conventional radiation therapy, the toxic response of FLASH-RT dose rate is significantly reduced and the irradiation time is significantly shortened, and these advantages make FLASH-RT a hot spot in the current radiotherapy field. This paper investigates the development status of FLASH-RT at home and abroad, summarizes the challenges to achieve its clinicalization, and...
Steady-State Microbunching (SSMB) proposes a novel mechanism for generating high-average-power coherent radiation spanning from THz to EUV, with significant potential for various applications. This paper presents the development of a laser system tailored to serve as the modulation laser for the second phase of the SSMB proof-of-principle (PoP) experiments. To verify the stability of...
The International Muon Collider Collaboration (IMCC) has been formed following the 2020 European Strategy for Particle Physics Update, with the goal of studying the feasibility of a muon collider at a centre of mass energy of around 10 TeV. One of the most challenging sections of a muon collider is the initial cooling before acceleration, due to the necessity to apply intense magnetic and...
It has been attracting attention that the energy chirp, which is formed by the space-charge effect of the electron beam and the beam wake field when the beam passes through the accelerator tube, can be used to generate short-pulse XFELs. Since the energy chirp produced by this phenomenon is such that the energy of electrons in the rear of the bunch is lower than at the front, compression...
SuperKEKB is an asymmetric lepton collider with 7-GeV electron and 4-GeV positron beams. The current vertical beta function (βy) at the collision point is set to 1 mm. Experimental results confirm that reducing βy leads to narrower dynamic apertures in both the horizontal and vertical directions, which in turn decreases the beam injection efficiency. This study presents a numerical...
One of the issues that the AuAu 100 GeV physics program in 2024 in RHIC encountered was background in the sPHENIX MVTX detector, which causes autorecoveries and preventing continuous data taking. Beam studies and track simulations performed to understand the source of the background and potential measures to control it have led to the conclusion that off-momentum particle loss was an issue....
The accelerator and Compton gamma-ray source research program at Duke Free-Electron Laser Laboratory (DFELL), TUNL, is focused on the development of the storage ring-based free-electron laser (FEL) and a state-of-the-art Compton gamma-ray source, the High Intensity Gamma-ray Source (HIGS) driven by the storage ring FEL. With a maximum total flux of about 3.5E10 gamma/s and a spectral flux of...
The ESRF plans to install an active 4th Harmonic Cavity to improve the performance of the EBS light source. Beam loading on the harmonic cavity induces a loss of longitudinal stability and needs to be deeply studied in order to find the optimum working point, both for the design of the harmonic cavity and for its operation. PyAT simulations will be presented to understand better the stability...
Finding the optimal RF voltage ramp to capture coasting beams in high intensity rings has been the subject of ongoing study for many decades. We are motivated to revisit the topic with a view to capturing coasting, stacked beams in a future high intensity, high power FFA. However, the results have general applicability. We compare various voltage laws including linear, bi-linear and...
The Large Hadron Collider (LHC) at CERN is the world’s most powerful particle accelerator, capable of colliding proton and lead ion beams at energies up to 7 ZTeV. ALICE, one of the LHC’s key experiments, is designed for studying heavy-ion collisions. A proposed fixed-target experiment within ALICE involves directing a portion of the beam halo, extracted using a bent crystal, onto an internal...
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...
When the closed-orbit spin tune is ramped linearly through an isolated spin-orbit resonance, the asymptotic polarization loss is well-approximated by the Froissart-Stora formula. However, it is often observed in accelerator simulations that the crossing speed, defined as the slope of the amplitude-dependent spin tune with respect to the machine azimuth, changes at the moment of resonance...
A test unit pulser for the proposed NIK (nonlinear in-jection kicker) project at TPS (Taiwan Photon Source) was fabricated in order to provide uniform kick strength applying onto the injected bunch train. This newly built flattop pulser gives much improved drive current pulse-shape in comparison with previously used half-sine pulser. This flattop pulser will result in high injection efficiency...
The beam dynamic design of a Drift Tube Linac (DTL) using plate drift tube combined an Interdigital H-mode (IH) cavity is proposed. This propose indicate that a DTL with a plate drift tube has an additional transverse focusing field without significant sacrifice to the longitudinal accelerating field. Based on this property, we established a new transverse focusing theory and completed a novel...
The Hefei Advanced Light Facility (HALF) is a diffraction-limited storage ring light source with a beam energy of 2.2 GeV. There are 13 insertion devices (IDs) will be installed in the storage ring, which have severe impacts on the low-energy beam. Especially for the long-period EPU, the non-linear effect can significantly reduce the dynamic aperture of the storage ring. In this paper, the IDs...
During the 2023 ion run at the LHC, where crystal collimation was regularly adopted for the first time, strong background levels were observed at the Inner Tracking System (ITS) of the ALICE detector. Some of the readout chips became saturated, causing losses of angular acceptance. This background was mitigated with using a dispersion knob in the beam optics, letting some residual background...
Free-electron lasers (FEL) seeded by short radiation pulses can exhibit superradiant behavior. In the superradiant regime, the pulse simultaneously compresses and amplifies as it propagates through the FEL, making superradiance very promising for pushing the performance limits of attosecond x-ray FELs. To date, this regime has been studied in asymptotic limits, but there is no model for how...
An electron energy measurement based on resonant spin depolarization has been running permanently at BESSY II for several years. This high-precision energy measurement was set up primarily for users of synchrotron radiation for meteorological applications from the German National Metrology Institute (PTB). Recent investigations have led to a better understanding of the method and to the...
The conditioning of room temperature cavities is a long process. Additionally, since the cavity or auxiliary equipment can be damaged, constant supervision or extensive safety precautions are required. To reduce the workload for everyone involved and to increase the efficiency of the conditioning process, it was decided to develop a machine learning algorithm with the goal of fully automated...
At J-Parc, the 500 μs long macro-pulses generated by the LINAC are separated into intermediate-pulses to synchronize it to the frequency of the Rapid-Cycling-Synchrotron (RCS). To secure a stable operation, the knowledge of position and length of those intermediate pulses are crucial, as the pulses need to be adjusted to the RCS frequency. The measurement for this adjustment is done by a beam...
FEL simulation codes are essential tools for simulating various FEL scenarios. Among the algorithms, the orbit-averaged algorithm is the most widely used due to its speed and low computational cost. The averaged algorithm simplifies physics model, so present codes such as GENESIS and SIMPLEX have limitations to model accurate features like FEL polarization and variations in electron beam...
The FCC-ee (Future Circular Collider) is a high-luminosity lepton collider study at CERN. Strong effects from quantum fluctuations, beamstrahlung, and Bhabha scattering limit the expected lifetime to well below one hour. Top-up injection continuously refills the colliding bunches to maximize the integrated luminosity.
The current baseline aims at using conventional on-axis injection and a...
The Isotope mass Separator On-Line facility (ISOLDE) delivers a wide range of low-energy radioactive ion beams to its experimental users. To meet varying demands, the facility uses different target materials, ionization methods, and cooling/bunching techniques, with beam configurations potentially changing weekly. To model particle transport through the transfer lines, it is essential to...
Ångström and attosecond represent fundamental spatiotemporal scales for studying electron dynamics in various materials. Recently, high-power attosecond hard X-ray pulses have been successfully demonstrated at the European XFEL using the self-chirping operation mode. However, the current process heavily depends on manual tuning by experienced operators, which is time-intensive and less...
Currently, a conventional local bump injection system with four pulsed dipole kicker magnets is adopted in the HLS-II storage ring to achieve top-off operation. Due to the nonlinear magnetic elements between the kickers in the HLS-II storage ring, the local bump injection presents technical challenges in forming a perfect closed bump, which causes the oscillation of the stored beam. In order...
The Future Circular lepton Collider (FCC-ee) will be an e+e- collider with beam energy spanning from 45.6 GeV to 182.5GeV. When operating in Z-mode, it will deliver the highest luminosity ever obtained in any lepton machine worldwide, and the stored beam energy will reach up to 18 MJ. Due to synchrotron radiation damping, the beam vertical size will be on the order of a few tens of um...
Beam Dynamic Analysis of An Electron Microtron Using General Particle Tracer.
Energy Recovery Linac (ERL) recovers energy from the used electron beam to accelerate the subsequent beam, greatly reducing the power consumed by the accelerator and harmful radiation. The use of Free-Electron Laser (FEL) light sources based on ERL has considerable potential for future development. This paper focuses on the optimization of the injector and merger part of a compact ERL FEL test...
Since 2015, the National Synchrotron Radiation Center SOLARIS has operated a light source supporting eight experimental beamlines. Following vacuum chamber replacements and beamline upgrades, the total beam lifetime at 400 mA has reached 13 hours in decay mode operation. Regular lifetime measurements are conducted to monitor vacuum quality, residual gas composition, and potential stability...
Muon colliders promise an efficient path to a multi-TeV energy collider facility. The final stage of the acceleration chain is planned to be a series of four rapid-cycling synchrotrons (RCS), in which the RF systems are divided into several sections and shared by the two counter-rotating muon bunches. The accelerator requirements are driven by the need to preserve the muon lifetime by taking...
SOLEIL-II is an ambitious upgrade project that aims to reduce the horizontal emittance of the SOLEIL facility from 4nm to 50pm. The SOLEIL-II lattice will utilise a combination of permanent magnets and electro-magnetic corrector magnets. In the case of beam losses, it is of critical importance to localise the losses to certain shielded areas or dedicated collimators in order to prevent the...
The Hefei Advanced Light Facility (HALF) which is a green-field diffraction-limited storage ring has a relatively low beam lifetime and very low beam emittance. So it is important to study the beam loss for the HALF storage ring to protect the insertion devices and optimize the radiation shielding. In this paper, a simulation for beam loss from two main mechanisms, beam dump and Touschek...
The Future Circular electron-positron Collider, FCC-ee, is a design study for a luminosity-frontier and highest-energy e+e- collider with a 91 km circumference. In a circular machine, the interactions between the beam particles and the residual gas in the vacuum chamber may degrade the beam quality, potentially affecting the beam lifetime and the collider luminosity, and cause local beam...
This paper describes the foil structure used at the beam extraction point in the NASA Space Radiation Laboratory (NSRL) beamline. The stripping foil removes electrons from incoming ions, rendering them partially or fully stripped. Foils of various materials and thicknesses are employed, enabling ion species at different energies to pass through. As charged particles traverse a foil, the...
In the electron-driven positron source of the International Linear Collider (ILC), positrons are generated through electromagnetic showers by irradiating a target with a 3 GeV electron beam and then accelerated in a positron capture linac in a solenoid magnetic field. Because of the high current multi-bunch beam requirements of ILC, the beam loading effect is one of the important issues. In...
Transverse stabilization of the beam in accelerators is crucial for optimizing any machine’s performance. The most common method for minimizing transverse beam jitter is the Balakin-Novokhatsky-Smirnov (BNS) damping technique. While this method has been successfully implemented worldwide, it has limitations in terms of beam quality preservation and acceleration efficiency, primarily because...
The Future electron-positron Circular Collider (FCC-ee) is a proposed lepton collider for high-energy particle physics succeeding the Large Hadron Collider (LHC). Its ambitious design goals demand excellent orbit and optics control and, therefore, set strict limits on alignment tolerances. One approach to relax the mechanical alignment tolerances is Beam-Based Alignment (BBA), where corrector...
Refining the present longitudinal impedance model is essential for an accurate prediction of beam stability thresholds. Longitudinal loss of Landau damping (LLD) for single bunches has been observed in the Large Hadron Collider (LHC). For High Luminosity (HL-) LHC beams, the present stability margin is aimed to be maintained. While coupled-bunched instability has not been detected in the LHC...
In Korea-4GSR, a beamline utilizing a canted ID is planned to be built. The impact of the electron beam resulting from the canting structure were investigated, and design modifications were implemented to minimize these effects. Simulation results show that the impact on the beam is negligible.
We developed a 6D multi-particle tracking program CETASim in C++ to simulate intensity-dependent effects in electron storage rings. The program can simulate the beam collective effects due to short-range/long-range wakefields for single/coupled-bunch instability studies. It also features the simulation of interactions among charged ions and the trains of electron bunches, including both fast...
Beam stacking is a key advantage of Fixed Field alternating gradient Accelerators (FFAs) for high-intensity applications. During stacking, one beam is stored as a coasting beam at the extraction energy while another, incoming beam is accelerated. However, the beam loss mechanism termed RF knockout can occur during stacking and undermine gains in extracted beam current. The accelerating RF...
High current linear accelerators require the precise alignment of accelerating cavities to maintain a high beam quality. The PERLE (Powerful Energy Recovery Linac for Experiments) injector cryomodule is composed of four single-cell cavities, each of which can be independently tuned to allow greater control of the beam at this crucial point. Misalignments can lead to perturbations in the beam...
The FCC-ee is a collider, proposed after the LHC era, based on a ring of approximately 90 km of circumference. It will have to be able to accommodate beams running at half the z-pole and tt ̅-pole with vertical Interaction point beam size less than 40 nanometer at the z. In the present studies, coherent ground motions are being explored with particle tracking tools such as MAD-X and analytics...
When a microbunched beam is sent to a resonantly tuned undulator it radiates coherent radiation with the intensity propotional to the bunching squared of the beam. According to *, the radiated energy increases with the undulator length. This conclusion, however, is only valid if one ignores the energy spread of the beam (and also the beam angular spread). The finite energy spread smears the...
To understand the risk of damage to the collimator blades and the permanent magnets in Diamond-II, the BDSIM code has been used to model the beam losses. To improve the accuracy, the engineering model and 3D field maps have been used to build the machine model. Energy deposition in the main storage ring components and the fluence of secondary particles (particularly neutrons) have been...
The CERN Super Proton Synchrotron (SPS) employs quadrupole-driven third-integer slow extraction to deliver beam to the North Area. This process is controlled by ramping all the magnets in the lattice, gradually driving the circulating beam into the tune resonance. In medical synchrotrons, Radio-Frequency Knock Out (RFKO) has proven to be a reliable alternative for driving the extraction...
The FLASH facility generates XUV and soft X-ray radiation in two FEL beamlines based on SASE and powered simultaneously by a single superconducting linac. To enable next generation user experiments a series of upgrades is coordinated within the FLASH2020+ project. Upgrades on the linac have been performed in a preparatory 9 month shutdown in 2021/2022 and have demonstrated to deliver an...
A 1.5-m linac is being installed at the hybrid gun’s beamline in UCLA Mithra Laboratory for the advanced accelerator research. A preliminary experiment by using a steering magnet showed the electron beam was accelerated from 4 MeV to greater than 30 MeV. A more precise measurement of the beam energy with a new spectrometer magnet is planned in early 2025 as well as the beam emittance. The...
Over the past year a new beamline dedicated to R&D for electron FLASH cancer radiation therapy and radiation biology was set up at the Photo Injector Test facility at DESY in Zeuthen (PITZ). The beamline runs in parallel to the SASE THz beamline at PITZ and is connected to it with an achromatic dogleg. The dispersion within the dogleg is utilized to install an aperture to scrape off-energy...
Following the successful commissioning of the soft X-ray planar undulator system (SASE3), the European XFEL user community expressed a strong demand to extend the radiation properties and provide the possibility to obtain variable polarization modes. It was therefore decided to build a helical afterburner behind the SASE3 system in collaboration with Paul Scherrer Institute (PSI). The final...
During the LHC run in 2024 two beam types were used for physics production with protons. A key difference between the standard 25 ns and the batch compression merging and splitting (BCMS) beams at injection into the LHC, is the smaller transverse emittance achieved with the latter in the injector chain. Despite both beam types appearing indistinguishable in the longitudinal plane, the BCMS...
A crucial component for designing particle colliders is the assessment of beam-beam effects at collisions. Particle In Cell (PIC) solvers are popular numerical tools, which solve the Poisson equation for the electromagnetic (EM) potential
$\Phi$ produced by the colliding beam's bunches spread on a discretized grid, and compute the Lorentz force acting on the particles subjected to the...
Xsuite is a collection of packages developed to simulate beam dynamics in particle accelerators. It includes Python modules (Xobjects, Xpart, Xtrack, Xcoll, Xfields, Xdeps) that can be seamlessly integrated with one another and with both accelerator-specific and general-purpose Python tools, enabling the study of complex simulation scenarios. The Xcoll module, developed for collimation...
The Dresden Advanced Light Infrastructure (DALI) project at Helmholtz-Zentrum Dresden-Rossendorf (HZDR) is a visionary initiative to establish a state-of-the-art light source facility, catering to cutting-edge research in materials science, biology, and other interdisciplinary fields. A cornerstone of this ambitious project is the development of an advanced accelerator lattice tailored to meet...
The SIS100 synchrotron, currently under construction as part of the FAIR project, is set to play a pivotal role in advancing high-intensity ion beam research. Reaching the FAIR design intensities for low charge-state heavy ions, e.g. the reference ion U28+ will, however, be challenging due to limitations of the existing SIS18 synchrotron serving as injector to SIS100. In the long-term, the...
UK XFEL is a multi-stage project to pursue ‘next-generation’ XFEL capabilities, either through developing a new facility in the UK or by investing at existing machines. The project’s Science Case envisages a step-change increase in the number of simultaneous experiments, with transform-limited (‘laser-like’) x-rays across a wide range of pulse durations and photon energies (up to ~20 keV)...
Round beam operation is considered for the planned ultra-low emittance storage ring PETRA IV at DESY, Hamburg. With a natural emittance of 20 pm rad, we evaluate and discuss the advantages and challenges of sharing the emittance between transversal planes. The effect on single and coupled bunch instability thresholds, intra-beam scattering rates and Touschek lifetime of this operation mode are...
Beam-based studies at the LHC injection energy showed that compensation of the strongly driven sextupolar resonance, Qx+2Qy, improved both the dynamic aperture and lifetime of the beam, even when far from the working point and on the far side of the 3Qy resonance. Thus, a reduction of other strong normal sextupolar resonance sources was of interest. In 2024, the first measurements of resonance...
As previously described*, high-intensity beams of ultra-bright light sources present new machine protection concerns by creating high-energy-density (HED) conditions in beam-intercepting components. Simulating these HED conditions required us to develop a method for coupling three codes for particle dynamics (elegant), particle-matter interaction (MARS/FLUKA), and hydrodynamics (FLASH). This...
The Electron-Ion Collider (EIC), to be constructed at Brookhaven National Laboratory, will collide polarized high-energy electron beams with polarized proton and ion beams, achieving luminosities of up to 1 × 10^34 cm^−2 s^−1 in the center-of-mass energy range of 20-140 GeV. Crab cavities will be used in both EIC rings to compensate for the geometric luminosity loss due to the large crossing...
The electron-positron Future Circular Collider (FCCee) will have a first phase of operation at the Z-pole energy of 45.6 GeV. To reach the target luminosity, a total of 11200 bunches with 2.14e11 charges will be used accounting for a stored energy of 17.5 MJ per beam. Given the small beam emittances, the beam energy density in turn reaches extremely high values. The potential to induce severe...
In the storage ring of a fourth-generation synchrotron light source such as the Hefei Advanced Light Facility (HALF), a multitude of vacuum elements interact with the beam current, thereby generating beam coupling impedance. This is a crucial factor contributing to beam instabilities and affecting the machine performance. Conducting impedance analysis on a vacuum element-by-element basis,...
Jefferson Lab’s Continuous Electron Beam Accelerator Facility (CEBAF) is currently investigating the feasibility of upgrading its maximum operating energy using Fixed-Field Alternating-gradient (FFA) recirculating arcs to increase the total number of recirculations the beam through the pair of LINACs. These FFA arcs will be composed of permanent magnets, with small Panofsky-style multipole...
SRF CW accelerator constructed for Coherent electron Cooling project at Brookhaven National Laboratory frequently demonstrated record parameters using 1.5 nC 350 psec long electron bunches, typically compressed to FWHM of 30 psec using ballistic compression. In this paper we report experimental demonstration of CW electron beam with parameters fully satisfying all requirements for hard-X-ray...
The lepton beams of the Future Circular Collider FCC-ee will store 17.5 MJ of energy per beam during Z mode operation. The damage potential of these beams is an essential input for the design of the machine protection system. In this paper, we first report the stored energy and energy density of the FCC-ee beams and compare them with the values for the Large Hadron Collider (LHC) and the...
A novel damping ring design and related transfer lines for the FCCee are proposed. The presented damping ring layout is optimized for operation at 2.86 GeV to efficiently cool both electron and positron beams and should cool down the transverse emittance of the positron beams by four orders of magnitude. The system accommodates beam trains consisting of 4 bunches separated by 25 ns, with a...
The RF photoinjector in LCLS-II produces several microamperes of dark current via field emission. While the vast majority of this dark current is collimated before reaching the first cryomodule, a small amount (typically less than 1 nA) is transported all the way to the beam switchyard (BSY) dump. In this contribution, we present the results of a start-to-end model of the transport of the dark...
The TWOCRYST proof-of-principle experiment at the LHC is an initiative to demonstrate the feasibility of a double-crystal setup for fixed-target physics experiments. Such a setup could enable spin precession studies of charmed baryons in the TeV energy range in the HL-LHC era. Major milestones in this project have recently been achieved, including the successful construction and testing of...
In this paper, we present the specification and design of a fast stripline kicker for enabling pseudo-single bunch operation in the SPEAR3 storage ring. We discuss both 2D and 3D RF structure designs, along with impedance calculations. Special attention is given to design considerations, including geometric constraints and the impedance impact of the small transverse aperture.
By designing a C-type nonlinear magnet, low emittance beam injection is realized on HALF.
The eddy current septum magnet composed injection system in the Hefei Advanced Light Facility (HALF). Leakage field from the septum magnet adversely affects the stored beam and can be reduced by shorter driving current pulse width. Theoretical explanations were proposed for this phenomenon. The effects of different drive current are simulated with the OPERA-2D TR analysis module. Measurement...
To realize the matching of RFQ and DTL, it is expected to place a three-gap rebuncher cavity with a frequency of 162.5 MHz in the MEBT section. The dynamics design parameters of the cavity have been determined, so this paper mainly focuses on the RF design and multi-physics field analysis of the cavity. Modeled in CST, the normal temperature CH-type structure is selected, in order to increase...
The electron gun is a crucial component of various vacuum electronic devices, including electron accelerators and electron microscopes. Prior to fabrication, designing and optimizing its geometry is a critical step to ensure optimal performance. In this study, the design and simulation of an electron gun for a linear electron accelerator are presented. The influence of key parameters on the...
Microbunched electron Cooling (MBEC) is a type of Coherent electron Cooling (CeC), suitable for cooling high energy protons; such an electron cooler can be driven by an energy recovery linac (ERL). The beam parameters of this design are based on cooling 275 and 100 GeV protons at the Electron-Ion Collider (EIC), requiring 150 and 55 MeV electrons, respectively. If implemented, a high energy...
The ESRF-EBS injection scheme consists in a classical four kickers off-axis injection. During injections, beam lines are perturbed and have to stop data acquisition. A new injection scheme using non-linear kickers was designed. The storage ring and transfer line optics and layout had to be modified to integrate the non-linear kickers in the injection cells and preserve injection efficiency in...
This study presents the design of an isochronous FFAG accelerator in the energy range of 3 to 150 MeV. A numerical method for solving the isochronous field is introduced, ensuring constant orbital frequencies across the energy range. The dynamic aperture was evaluated, multi-particle simulations were conducted to assess the impact of space charge effects on beam stability at different beam...
Shenzhen Superconducting Soft X-Ray Free Electron Laser (S3FEL) is a high-repetition-rate and high-brightness soft X-ray facility under construction. It is designed to support multiple user experiments simultaneously, each requiring different undulator lines and FEL parameters. This capability is made possible by the beam spreader system, which plays a pivotal role in transporting the electron...
Laser-plasma accelerators (LPAs) produce high-quality electron beams with the GeV-level of the energy, the high peak currents and low emittance, making them ideal for compact novel free-electron lasers (FELs). However, the large angular divergence and energy spread of these beams pose challenges for efficient beam transport and overall FEL performance. This study explores the use of an active...
The fourth generation HALF light source is a kind of storage ring light source based on diffraction limit. On the one hand, the shielded bellows in the vacuum system is used to compensate the thermal expansion and cold contraction of the vacuum chamber, and to adjust the longitudinal and transverse offset of the vacuum chamber according to the requirements of installation and collimation, on...
A high β injection section is introduced to further increase the dynamic aperture for the HALF storage ring. In this paper, three different high β injection straight section designs are presented. In the design, an additional family of focusing quadrupoles is added to increase the horizontal-β function. The first design referes the injection section of the ESRF-EBS lattice, with a focusing...
A new 4th Generation Storage Ring (4GSR) will be constructed in Ochang, South Korea, by the end of 2029. A technical design review for the Korea 4GSR was completed at the end of 2023. The storage ring has a circumference of 799 meters and is designed for a maximum current of 400 mA at 4 GeV electron beam energy. The target emittance is below 100 pm-rad, with a calculated emittance of 62...
The Super Tau-Charm Facility (STCF) is an electron-position collider proposed in China. The injector of STCF provides high quality electron and position beams at an energy up to 2.5 GeV at a repetition rate of 30 Hz. The beam transport system is composed of the electron bypass transport line, the transport lines from positron Linac to Damping Ring and from Damping Ring to positron Linac, and...
The FCC-ee injector complex aims to deliver tunable, high-charge electrons and positron bunches for injection into a collider operating at center-of-mass energies from 90 to 365 GeV. The injector complex includes multiple linacs that sequentially boost the energy of the bunches to the booster injection energy of 20 GeV. This work addresses the significant challenges posed by the required beam...
The muon collider has great potential for enabling high-luminosity multi-TeV lepton-antilepton collisions provided low-emittance, high-intensity muon beams can be produced. Ionization cooling is the proposed technique to achieve the required muon beam emittance. The International Muon Collider Collaboration aims to demonstrate the integration and reliable operation of a 6D ionization cooling...
In this work we examine the progress made in the design of the proposed FFA upgrade to the Continuous Electron Beam Accelerator Facility (CEBAF). This proposed upgrade will double the number of passes through the two linacs by replacing the two highest energy arcs with new Fixed Field Alternating Gradient (FFA) arcs, roughly doubling the energy. These FFA arcs will use permanent magnets in a...
The Electron-Ion Collider (EIC) aims at a luminosity of 10^34 cm^-2 sec^-1. Its Electron Storage Ring (ESR), which will be installed in the existing RHIC tunnel, will store electron beams from 5 to 18 GeV with beam currents up to 2.5 A. The design of the ESR has matured substantially. We will report the design status, including beam dynamics and polarization aspects, value engineering...
We have designed three types of septa—thin septum, thick septum, and DC septum—for the Korea-4GSR project, a 4 GeV diffraction-limited storage ring incorporating a 200 MeV LINAC and booster synchrotron. The thin septum is an in-vacuum pulsed septum magnet, the thick septum is an out-vacuum pulsed septum magnet, and the DC septum is an out-vacuum DC magnet. This presentation focuses...
The adoption of Solid State Power Amplifier (SSPA) is rapidly increasing in major accelerators worldwide, replacing tube amplifiers such as Klystron and IoT. This study aimed to develop a High-Power RF system for Multipurpose Synchrotron Radiation Accelerators and to design and implement a GaN transistor-based SSPA. Through this research, we verified control performance equivalent to that of a...
Optical stochastic cooling (OSC) is a recently demonstrated state-of-the-art method for beam cooling and control. The strength and utility of OSC can be greatly extended by the inclusion of a high-gain optical amplifier in the system. The amplifier is necessarily a bespoke system whose design and implementation are highly constrained by the OSC physics and system design. In this report, we...
In the scope of the renewal of its injection systems, the ESRF-EBS has decided to implement a new scheme using Non-Linear Kickers (NLK) magnets. These pulsed octupole like magnets are extremely sensitive to any misalignment of the conductors carrying the currents resulting in a degraded magnetic field quality. It is then important to characterize precisely the transverse magnetic fields of...
The linear accelerators of the Taiwan Photon Source has been fully operating for more than 10 years. Considering components’ aging issues and a shortage of supply chain due to phase-out parts, an alternative solution for these components with the same functionality must be prepared in case of need in order to ensure the TPS Linac’s smooth operation. In this report, a new 6-axis step motor...
In an effort driven by the requests from different physics experiments at CERN, the CERN ion injector complex is looking to expand its capabilities by providing lighter-than-lead ion beams. Argon and xenon were delivered for NA61/SHINE physics in 2015 and 2017, with xenon also reaching the LHC in 2017. Oxygen is foreseen to be collided in the LHC in 2025, with magnesium, boron and krypton...
The compact ERL has been built in 2013 at High Energy Accelerator Research Organization (KEK) to a test machine of an energy recovery linac. Afterwards, two undulators have been installed in the compact ERL and a first light amplification (free-electron laser: FEL) in mid-infrared range has been observed in 2021. However, the intensity of light has not been achieved to the intensity saturation...
In the pursuit of higher brightness, the fourth generation of ring-based storage ring light sources, pushing the emittance close to the diffraction limit of X-rays by means of multi-bend achromat (MBA) lattices, are being operated, constructed, or designed worldwide. Among various MBA lattice designs, the Diamond-II type lattice, such as a hybrid-MBA lattice with a short straight section...
The baseline design for the proposed UK XFEL (United Kingdom X-ray Free Electron Laser) facility includes main linear accelerating linacs, which are comprised of more than 500 9-cell TESLA style superconducting RF cavities, which will accelerate a 1 MHz repetition-rate electron beam comprised of 200 pC bunches up to an energy of 8 GeV. Here the TESLA cavities are simulated and the dipole modes...
A large momentum acceptance (MA) in 4th generation storage ring light sources is paramount to obtaining a long Touschek lifetime. However, the calculation of MA typically requires computationally expensive tracking simulations thereby complicating, or even disabling, the direct optimization of Touschek lifetime using numerical optimization algorithms. Our recent development of Fast Touschek...
Heavily populated transverse beam tails can be an issue for the operation and the performance of present and future particle colliders. In this respect, the tailoring of beam distributions through transverse halo scraping is a powerful technique for limiting beam losses and maximizing beam lifetime. By doing so, a portion of the bunch intensity is sacrificed, to the benefit of a reduced bunch...
A dual-purpose structure has been developed for the NICA collider accelerating heavy multiply charged ions and light polarized nuclei of protons and deuterons. For heavy multiply charged ions, it is necessary to solve the problem of intrabeam scattering, which requires minimal modulation of the envelope and dispersion function. For light particles, the problem of crossing transition energy...
The Ring Electron Cooler is one option to provide cooling to the Electron Ion Collider’s 275 GeV proton bunches. Using traditional electron cooling this racetrack shaped storage ring uses one straight section to cool the protons and the other one to enhance the radiation damping of the electrons using 2.4 T wigglers. These sections comprise the majority of the ring and are connected by short...
The electron-ion collider (EIC), under design at Brookhaven National Laboratory, will consist of two storage rings for collisions of polarized electron and hadron beams. A sufficiently large dynamic aperture (DA) is required in the electron storage ring (ESR) at different energies (5-18 GeV) to ensure an adequate beam lifetime. The DA is limited by the effects of non-linear field and magnet...
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 ("modulators"), each followed by a magnetic chicane, an electron phase space structure with high harmonic content is produced, which gives...
Crab cavities, operating at 197 MHz and 394 MHz respectively, will be used to compensate the loss of luminosity due to a 25 mrad crossing angle at the interaction point in the Electron Ion Collider (EIC). Both cavities are of the RF Dipole (RFD) type. To meet the stringent impedance requirements for beam stability and quality, the cavity design must incorporate strong Higher Order Mode (HOM)...
Electron beam and laser-Compton X-ray parameters stabilization simulation study at KEK Laser-Undulator Compact X-ray facilityis a normal conductivity multi-bunch electron linear accelerator devoted to develop an intense monochromatic source of laser-Compton X-ray for tomography applications.
The electron beam parameters absolute values and its stability were simulated at the ASTRA tracking...
The latest injector complex design of the FCCee project includes electron linac, positron source and positron linac, which accelerates the beams up to 2.86 GeV, a damping ring at 2.86 GeV for both beams and a high energy linac accelerating the beam up to 20 GeV before the beams are transferred into the booster synchrotron ring integrated in the collider tunnel accelerating the beams up to the...
The Electron-Ion Collider (EIC) aims to achieve a peak luminosity of 10^34 cm^−2s^−1 through polarized electron-proton collisions. The Electron Storage Ring (ESR) is designed to deliver high-charge electron bunches of up to 28 nC with a dynamic aperture of 10σ in all three planes. Given the limited polarization lifetime, frequent electron bunch replacement is necessary, making the swap-out...
Recently, the emittance of the Taiwan Photon Source (TPS) was re-evaluated using two methods: measurements of the coupling strength between horizontal and vertical motion, and data from the pinhole camera. However, a significant discrepancy was observed between these two approaches. To address this issue, several possible explanations have been proposed, involving a thorough examination of the...
The Future Circular Collider (FCC), in its leptonic configuration has been chosen by CERN as main proposition for the next high-energy collider. This project aims to achieve luminosities one to two orders of magnitude higher than ever. Feasibility studies have led to the definition of tolerances on magnet imperfections and correction strategies. This is crucial for ensuring the performance of...
During 2022 and 2023 LHC optics commissioning, it was observed that at low-beta small changes in the beam-energy could generate substantial perturbations of the linear beam optics, requiring re-commissioning of local corrections in the experimental insertions. This issue may become even more significant at the very low beta anticipated for operation in the High Luminosity LHC (HL-LHC)....
Brookhaven National Laboratory (BNL) is the host site for the future Electron-Ion Collider (EIC), a high-energy, high-luminosity polarized collider that will be one of the most challenging and innovative accelerator complexes ever built. BNL has assembled a team of highly skilled engineers in RF Technology, Vacuum Systems, Beam Instrumentation, Power Supplies, Controls, Magnets and Cryogenics;...
Enhanced self-seeding (proposed in Phys. Rev. Lett. 125, 044801, 2020) is a concept for more stable, laser-like XFEL operation. The principle of enhanced self-seeding lies in strong lasing on the current spike in the SASE section, and picking the seed pulse with the flat, lower current portion of the beam. Recently, we performed experimental studies of this scheme with the existing hard x-ray...
The existing synchrotron SIS18 will serve as an injector for the FAIR (Facility for Antiproton and Ion Research) complex in booster mode operation. FAIR requires high-intensity beams, placing stringent demands on increasing beam currents in SIS18. Operational experience has shown that significantly increasing beam intensity in SIS18 necessitates both a higher current from UNILAC and improved...
Across its energy range, the beam lifetime at the Future Circular Collider $e^+e^-$ (FCC-ee) will be dominated by radiative processes occurring as a result of the beam-beam collision, namely by beamstrahlung and small angle radiative Bhabha scattering. Although approximate analytical expressions exist for estimating the lifetime, it is most accurately evaluated by performing multiparticle...
Error analysis and estimation of accuracy in the experiment on precise mass measurement of Y(1S)-meson on the VEPP-4M with KEDR detector collider was presented. The resonant depolarization technique with laser polarimeter was used for beam energy calibration.
This study looks at the relationship between titanium coating thickness and thermally deposited power in the ceramic chambers of nonlinear in-vacuum kickers (NIK), which are critical components of synchrotron light sources. Simulations show that as coating thickness increases, magnetic field attenuation increases, whereas thinner coatings result in greater thermal power deposition. The study...
This study explores the feasibility of using Compton Backscattering (CBS) as a compact source for generating photons in the extreme ultraviolet (EUV) to soft X-ray range, with potential applications in biological imaging and modern lithography. A CBS experiment was conducted at the AWAKE Run 2c test injector (ARTI), where electron bunches, accelerated up to 6 MeV by a high-gradient,...
Several laboratories and facilities recently started joined efforts towards the realization of a python accelerator middle layer (pyAML) for control, tuning and optimization. This software is intended as a successor to matlab middle layer (MML), inheriting its features but also expanding to new ones (e.g., nonlinear optics and machine learning tools). Presently, several codes are available...
The design of lattice candidates for the Taiwan Photon Source (TPS) upgrade, based on Multi-Bend Achromat (MBA) and Hybrid Multi-Bend Achromat (HMBA) configurations, is under investigation. The system parameters are carefully optimized in order to satisfy all the constraints, particularly minimizing the offset of source points at the existing insertion devices (IDs). The 6BA configuration...
Recently, the Hard X-ray Self-Seeding (HXRSS) setup at the European XFEL has been successfully demonstrated, achieving routinely pulse energies in the seeded signal of several hundreds of microjoules at various wavelengths. However, the shorter wavelengths pose a challenge to the impulse response of crystal, limiting output radiation and spectral performance. To address these challenges, a...
Many different techniques have been investigated at Diamond for optimising sextupole strengths*. One method not previously studied is to exploit the null space of the chromaticity response matrix. By performing a singular value decomposition (SVD) of the chromaticity response matrix, combinations of sextupole strengths are identified which alter the nonlinear lattice whilst keeping the...
Three horizontal and three vertical collimators will be installed in the Diamond-II storage ring to collect lost particles and provide machine protection. Due to the small electron beam emittance however, there is a risk that damage to the collimator blades could occur following a full beam loss. In addition, the collimators are located upstream of the permanent magnet dipoles, which could be...
The electron-positron Future Circular Collider (FCC-ee) is a proposed high-energy lepton collider that aims to reach unprecedented luminosity and precision in the measurement of fundamental particles. To fully profit of such performance, it is crucial to keep detector backgrounds under control and operate the machine safely. Due to the high stored beam energy and to a number of complex...
The Future electron-positron Circular Collider, FCC-ee, aims at high-precision particle physics experiments with beam energies from 45.6 to 182.5 GeV, corresponding to the Z-pole up to above the top-pair-threshold. These goals demand, among others, a precise knowledge of the center-of-mass energy and, hence, the beam energies. By depolarizing previously polarized pilot bunches and recording...
The proposed FCC-ee machine is a high-energy, high-intensity and high-precision lepton collider which will require to reduce drastically the differential motions of its two beams at the interaction points (IPs). All undesirable effects on the beam parameters must be analysed in detail, especially in the vicinity of the IP but also along the collider. To assess the beam effects due to...
Optics tuning and correction in the Interaction Point (IP) region of the FCC-ee is critical for achieving the target luminosity. By utilizing dedicated IP tuning knobs, lattice errors at multiple IP's are corrected to restore the design optics, enabling dynamic aperture studies on the fully corrected lattice. These studies, conducted using the pyAT optics code, assess the impact of corrections...
FCC-ee luminosity optimization relies on measuring realistic signals from Bhabha scattering, beamstrahlung, and radiative Bhabha photons. Initial assessments of beamstrahlung signals examine the change in luminosity, beamstrahlung power and vertex detector hits in response to waist shifts, vertical dispersion and skew coupling at the collision point. These ongoing studies aim to extract...
The FCC-ee is a future high-luminosity circular electron-positron collider aiming at achieving unprecedented luminosities with beam energies ranging from 45.6 up to 182.5 GeV. FCC-ee demands precise optics tuning to achieve its ambitious performance goals. This study investigates the tuning and correction of FCC-ee optics under simulated magnet misalignments, with a particular focus on the...
The secondary radiation fields generated by synchrotron photons pose a significant challenge for equipment in high energy electron and positron storage rings like the Future Circular Collider (FCC-ee) at CERN. The annual ionizing dose can reach MGy-levels in the FCC-ee tunnel and requires the design of a dedicated radiation shielding enclosing the photon stoppers in dipoles. In this paper, we...
CERN’s Future Circular Collider (FCC) comprises a ~91 km circumference lepton collider and its injector complex. This contribution summarises the feasibility studies performed for the various kicker systems needed to transfer the beam between the different machines. The individual system requirements are reviewed, recent changes are highlighted, and the chosen conceptual design is outlined....
In the context of ongoing research for a future muon collider, one of the primary challenges is the efficient production and cooling of muons. To address this, a proposal is being explored to construct a demonstrator at CERN for testing a cooling cell. This demonstrator would include a target and focusing system, a chicane around a dump, and a cooling channel. A potential site for this...
This study explores the feasibility of implementing stochastic cooling in the proposed proton electric dipole moment (pEDM) storage ring to be constructed at Brookhaven National Laboratory. Investigating fundamental physics phenomena, such as the electric dipole moment (EDM) of protons, demands highly precise experimental setups. In such precision experiments, intra-beam scattering (IBS)...
A phase shifter collocated with an undulator is an efficient method to enhance the lasing performance of free-electron laser (FEL), particularly for seeded FEL. Dalian Coherent Light Source (DCLS) is a seeded FEL facility operating in high-gain harmonic generation (HGHG) mode to produce fully coherent vacuum ultraviolet laser. To achieve high FEL lasing performance, five phase shifters are...
The Electron-Ion Collider (EIC), to be constructed at Brookhaven National Laboratory, will collide polarized high-energy electron beams with polarized proton and ion beams, achieving luminosities of up to 1 × 10^34 cm^−2 s^−1 in the center-of-mass energy range of 20-140 GeV. Based on the experience from the Relativistic Heavy Ion Collider (RHIC), magnetic field errors in the interaction region...
A new lattice for the EBS is proposed as preliminary candidate for the next generation ESRF storage ring. This new optics would feature lower emittance, matched optics at all ID, transparency conditions for insertions and overall a net gain in brilliance coherence and flux. Due to the reduced dynamic aperture, on-axis injection with a low emittance beam would be a requirement in order to...
FLASH, the XUV and soft X-ray free-electron laser at DESY, is currently undergoing the 2nd of two long upgrade shutdowns within the FLASH2020+ project. The 1st half of 2024 was dedicated to user operation. The upgrade shutdown started in June 2024, and we plan to come back to beam operation in August 2025.
Here we will discuss the operational highlights of the first half of 2024,
briefly...
The Energy Recovery Linac (ERL) combines the high repetition frequency of synchrotron radiation with the high brightness of FELs, showing great potential. Despite recent breakthroughs, the electron beam quality still fails to meet the requirements for driving short-wavelength FELs.
The method combining ERL with Angular Dispersion-induced Microbunching (ADM), proposed by the Shanghai Light...
The polarization of the gamma-ray beam plays a critical role in experimental photonuclear research by probing angular momentum. For example, the multipolarities of the 80Se(g,n)79Se reaction can be assigned by measuring cross-sections relative to the plane of polarization*. Dynamic control over gamma beam polarization will open new opportunities in nuclear research, particularly by allowing...
This study explores the feasibility of generating high-energy photons, reaching up to 150 GeV, at the FCC-ee booster through inverse Compton scattering. The proposed scheme utilizes a laser within a Fabry-Perot cavity, enabling high repetition rates while minimizing recoil effects during individual collisions. This approach supports the potential use of the FCC-ee booster as a high-energy...
Generating few- or sub-femtosecond radiation pulses in a free-electron laser requires precise control of the longitudinal phase space density of the driving electron bunch, as the FEL process depends strongly on the bunch current- and energy spread profile. In an experiment conducted at FLASH, an energy modulation with linearly increasing amplitude is imprinted onto part of the bunch by a...
None
The High Luminosity Large Hadron Collider (HL-LHC) presents significant collimation challenges due to its high stored beam energy. An effective collimation system is critical for ensuring stable operation, protecting the superconducting magnets and minimizing background to the experiments. This paper examines the current baseline collimation configuration and potential changes to the...
The Electron-Ion Collider (EIC) to be built at Brookhaven National Laboratory will be the first collider of longitudinally-spin-polarized electrons with longitudinally-spin-polarized ions for a wide range of energies. In the Electron Storage Ring (ESR) of the EIC, the minimization of radiative depolarization faces several significant challenges, including engineering limitations, the necessity...
With a natural emittance of 26.3 pm·rad and a circumference of 810 m, the preliminary design for the Southern Advanced Photon Source, a 3.5 GeV ultra-low emittance storage ring, was proposed in 2023. The design provides sufficient dynamic acceptance for on-axis injection, supporting not only swap out injection but also longitudinal injection. Recently, to explore the possibility of off-axis...
With the upgrade from PETRA III to PETRA IV the requirements concerning the beam parameters increase. Thus, a special focus is placed on the suppression of higher order modes (HOMs) in the accelerating systems.
An Investigation of the already presented single mode structure showed the emergence of certain higher order modes. These cavity eigenmodes are now examined by evaluating and...
The international linear collider (ILC) is a Higgs Factory, where electron-positrons are accelerated by the linear accelerators using Superconducting RF (SRF) cavities to 125 GeV. In 2013, the GDE, an international organization of researchers, already compiled the TDR. It is currently being studied under the International Development Team (IDT). Especially, from 2023, the ILC Technology...
The electron positron Future Circular Collider (FCC-ee) is considered the primary contender for the next major particle accelerator within the European Strategy for particle physics, aiming to achieve unprecedented luminosities to enable precise measurements of Z, W, and H bosons along with the top quark. Despite its potential, the FCC-ee project faces significant operational and design...
The Future Circular Collider for electron-positron collisions (FCC-ee) is a proposed next-generation particle accelerator aimed at achieving high luminosity and precision for fundamental particle physics experiments. Its performance is sensitive to environmental factors such as ground motion, which can induce vibrations and misalignments in critical accelerator components. This paper presents...
The performance of the Future Circular Collider (FCC-ee) is influenced by a complex interplay of effects, including misalignment and magnetic errors, experimental solenoids, synchrotron radiation, and beam-beam interactions. Additionally, design choices such as relaxed optics, varying beam sizes, and differing bunch charges can significantly alter the machine's dynamics. This study explores...
In this study, we perform impedance convergence analyses for beam position monitor (BPM) and the complex bend prototype vacuum chamber designed for the NSLS-II upgrade using EHO3D and GdfidL. The longitudinal and transverse (dipole) wake potentials are computed for various bunch lengths and mesh resolutions to evaluate the convergence and reliability of the simulation results. Our findings...
Muon colliders offer high-luminosity, multi-TeV collisions without significant synchrotron radiation but require further exploration of muon production, acceleration, cooling, and storage techniques. A proposed 6D cooling demonstrator aims to extend the MICE experiment's validation of transverse ionization cooling to also reduce longitudinal emittance, using bunched muon beams and...
Accurate determination of magnet centres seen by beams is the key to a successful commissioning of a particle accelerator storage ring. In this paper, several techniques to improve the beam-based alignment for a circular accelerator storage ring are introduced. Firstly, a formula to propagate the uncertainties from linear fitting is given. Secondly, a reliability weighted averaging technique...
FLASH is an XUV and soft X-ray free-electron laser (FEL) facility that contains a superconducting linear accelerator with a beam energy of up to 1.35 GeV which drives two FEL beamlines in parallel and a plasma wakefield accelerator experiment called FLASHForward. Within the upgrade program FLASH2020+, a laser heater was installed upstream of the first bunch compression chicane to mitigate...
Synchrotron radiation light sources normally operate at a low coupling between the transverse planes in order to achieve flat beams and produce high peak brilliance. Instead, operating at a high coupling has other advantages such as smaller emittance degradation due to intra-beam scattering, improved Touschek lifetime, and lower sensitivity to vibrations of the photon beam. Moreover, it has...
ANSTO is developing a fourth generation light source design, currently called AS2. In this paper we will detail the injection scheme that uses a non-linear kicker for off-axis injection into a ring of small dynamic aperture.
In an FEL oscillator with a planar undulator, odd harmonics appear as either spontaneous emission or as linear and nonlinear harmonics associated with the FEL pulse evolution. Additionally, misalignment of the electron beam or the resonator can lead to off-axis gain, generating even harmonics. We conducted an experiment at KU-FEL, operated at 5 µm, to measure the 6th- and 7th-harmonic spectra...
The Future Circular Collider of electrons and positrons (FCC-ee) is designed to achieve high luminosity at center-of-mass energies ranging from the Z boson peak to the top quark threshold. During the commissioning phase, specialized optics are essential to accommodate the dynamic needs of machine tuning and beam stabilization. This paper investigates the role of sextupoles in the various...
With the LHC achieving luminosity precision at the percent level, accounting for linear coupling becomes crucial. This effect is caused by skew quadrupoles and can be studied during van der Meer (vdM) scans performed for absolute luminosity measurements and detector calibration. A bias is induced as the nonlinear beam-beam force and the linear coupling makes the charge distribution of the...
The GSI Facility consists of several accelerators, offering the distinctive capability to provide different beams with varying characteristics to a range of experiments simultaneously. In order to facilitate the monitoring of machine performance across diverse beam production chains and experiments, a Key Performance Indicator (KPI) matrix has been introduced. The CRYRING@ESR team has carried...
The current achieved highest luminosity at SuperKEKB is only one-tenth of the design value, and beam injection is one of the most serious issues in achieving the target luminosity. Recent operations in both the HER and LER rings have shown insufficient injection efficiencies and detector backgrounds. The achieved injection efficiency falls short of the required level, sometimes leading to...
Currently, SuperKEKB faces the challenge of sudden beam loss (SBL), which occurs with almost no prior sign. The causes of SBL are not fully understood. A damaged collimator reduces its ability to suppress beam background noise compared to an undamaged one. In cases that the beam background noise reduction decrease, it is necessary to stop the operation and replace the collimator jaw....
During operation for luminosity production, the LHC runs with very strong Landau octupoles to ensure the collective stability of the beams. A disadvantage of this is that these octupoles can drive resonances which can be detrimental to beam lifetime. Recently, a special optics configuration has been utilised to reduce the impact of the main octupoles on lifetime. This design relies on...
Attosecond x-ray pulses play a crucial role in the study of ultrafast phenomena involving inner and valence
electrons. Especially isolated attosecond pulses with high photon energy and high peak power are of great
significance in single-shot imaging in the soft x-ray region, life sciences, and attosecond pump-probe experiments. In modern accelerators, laser manipulation of electrons can be...
At the Los Alamos Neutron Science Center (LANSCE) the first 100 MeV of acceleration are currently accomplished with a Cockroft-Walton generator (750 keV), followed by 4 drift tube linac (DTL) cavities. Increasing obsolescence and reliability problems for this 52-year-old equipment have created the need for replacements and upgrades. The Los Alamos Modernization Project (LAMP) is developing a...
In this study, we explore the application of laser-driven Compton backscattering (CBS) as a method to precisely adjust and regulate the intensity of colliding particle bunches in the Future Circular Collider (FCC-ee). Maintaining a tightly controlled charge balance between collision partner bunches within a 3–5% tolerance is critical for mitigating the impact of beamstrahlung on bunch length...
Precise determination of the center-of-mass energy at the Future Circular Collider (FCC-ee) operating at the Z and W resonance energies relies on resonant spin depolarization techniques, which require a sufficient level of transverse beam polarization in the presence of machine imperfections. In this study, the FCC-ee lattice is modeled and simulated under a range of realistic imperfections,...
The HALF storage ring is a 2.2 GeV diffraction limited storage ring, with radiation photons mainly in the vacuum ultraviolet (VUV) to soft X-ray wavelength ranges. In order to meet the demand for high brightness hard X-rays, HALF plans to replace 0.9 T normally bending magnet with 6 T superbend. This paper reports two lattice design schemes, replacing one bend and two bends respectively. The...
Insertion Region 2 (IR2) of the Relativistic Heavy Ion Collider will be modified to provide effective cooling for the Electron-Ion Collider (EIC). This paper summarizes the update of the HSR-IR2 lattice design to meet the evolving requirements of the EIC. The geometry has been redesigned to satisfy the yellow-to-yellow configuration, while also accommodating future integration of the 41 GeV...
Synchrotron radiation source has many advanced characteristics such as high brightness, transverse coherence, good time structure, etc, which is developed as one of the most powerful scientific tools over decades. Due to the great performance of radiation based on the light source, it plays an important role in the science researches of quantum materials, catalytic science, bioscience, etc. In...
SLAC’s LCLS-II is advancing towards MHz repetition rate attosecond X-ray pulses, creating opportunities to optimize X-ray generation through machine-driven controls and diagnostics via start-to-end simulation. Advanced laser shaping and upconversion techniques at the photoinjector, such as spatial light modulator-based pre-amplifier pulse shaping linked to nonlinear methods such as...
The ESRF booster has been built more than 30 years ago as injector of the first ESRF storage ring and it is still used to inject in the EBS. Several components of the booster have been updated in the years and it is now operated off-energy and with emittance exchange at extraction, however the lattice has not been modified since the '90s. A project to reduce the equilibrium emittance and...
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...
SuperKEKB is a double ring collider consisting of a 7 GeV electron ring and a 4 GeV positron ring with a circumference of 3 km built 11 m below the ground level.
SuperKEKB was constructed by reusing the KEKB tunnel, which was originally excavated for TRISTAN accelerator in early 1980s. SuperKEKB utilizes “large angle nano-beam scheme,” where two low emittance beams collide with a large...
For diffraction-limited storage rings, the triple radio-frequency (RF) system has been proposed to achieve further bunch lengthening or to meet specific requirements for longitudinal injection. The choice of RF cavity parameters for the triple RF system has a significant influence on the longitudinal beam dynamics. Macro-particle tracking simulation is commonly used to accurately analyse this...
The intra-beam scattering in high charge state intense heavy ion beams is a problem worth considering. With the help of controlling the longitudinal distribution of the ion beam, it may be possible to alleviate the ion beam loss and to improve the ion beam lifetime caused by intra-beam scattering. Unlike the traditional cooling process of direct current electron beams or longitudinal uniform...
The Hefei Advanced Light Facility (HALF) is a vacuum ultraviolet (VUV) and X-ray diffraction-limited storage ring light source. It has a relatively large dynamic aperture, and an injection scheme with a nonlinear kicker (NLK) was considered for the HALF. This kind of magnet was designed with a small gap shield in the central area to gain a flat magnetic field. A complete prototype has also...
The influence of longitudinal wakefields on the beam dynamics in electron-positron colliders, particularly their role in beam instabilities such as Transverse Mode Coupling Instability (TMCI) and other transverse-longitudinal effects, necessitates a robust approach to accurately model these effects. This work focuses on the implementation of wakefield effects in the Circulant Matrix Model...
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 has given great impetus to the idea of electron acceleration using wakefields by propagation intense laser pulse in plasma (LWFA). Several experiments have been done to demonstrate laser wakefield acceleration of charged...
The Muon Collider is a proposed future accelerator for very high energy muon collision. Since muons are heavier than electrons, the synchrotron radiation is negligible at this high energy, allowing to build a compact machine able to deliver Multi-TeV c.o.m. energy collisions, enabling precision measurements of the Standard Model quantities and search for new physics. A challenge of a muon beam...
Electron storage rings based on multi-bend achromat (MBA) lattice can achieve very low natural emittances. Several fourth generation light sources have been built and operating, the natural emittances of which are a few 100 pm or even lower than 100 pm, providing high brightness photon beams to users. Since the lattice of MBA storage ring tends to be highly compact, the field of a magnet may...
The muon collider represents a transformative approach in particle
physics, offering a pathway to achieve high energy and luminosity with
reduced environmental impact compared to other collider technologies.
Central to its feasibility is the development of advanced magnet systems
capable of supporting the stringent requirements of muon production,
acceleration, and collision. The key...
The MAX IV 3 GeV storage ring in Lund, Sweden, was the first implementation of a multibend achromat (MBA) lattice fourth-generation light source. Since it started delivery of light in 2016, three succeeding MBA-based rings and variants have come on-line: ESRF-EBS, Sirius and APS-U. Several others are being planned, designed, built or commissioned. All of these capitalize on the MBA concept and...
The hard X-ray undulator line, Aramis, at the free-electron laser SwissFEL at Paul Scherrer Institute has been in user operation at full beam energy since end of 2018. After continually improving the performance until 2022, we had been struggling to maintain these high-performance levels and dealt with slowly degrading pulse energies and failure to reproduce “good performance”. After a...
In this study, we present the latest measurements of intrabeam scattering (IBS) effects at NSLS-II and compare them with particle tracking simulations using ELEGANT. The growth of horizontal and vertical emittances, as well as bunch length and energy spread, is observed as a function of single-bunch current. Simulations, including IBS and longitudinal wakefields modeled using a broadband...
The Electron Ion Collider (EIC) Rapid Cycling Synchrotron (RCS) requires highly polarized, high intensity beam at 3 GeV injection that can be ramped to 18 GeV. The need to maintain beam stability at injection for the high intensity bunch requires increased damping that is not provided without the use of a Static Field Damping Wiggler (SFDW). This paper describes bunch stability challenges at...
SuperKEKB, located at KEK, is a second generation B-factory, providing beam to the Belle-II experiment. Optics design and simulation of SuperKEKB were previously performed using the optics code SAD, developed at KEK. In this paper, we present a new model of SuperKEKB using the tracking code Xsuite, developed at CERN. An alternative strategy for modelling the interaction region, with...
For the FCC-ee collider it is planned to, in regular intervals (minutes), measure the average beam energy of the circulating electron and positron beams with a relative precision of $10^{-6}$ or better, using the method of resonant depolarisation with pre-polarized pilot bunches. In this article, we study basic systematic effects and ultimate uncertainties that may arise in this kind of...
High-dimensional phase space reconstruction is an important tool for achieving precise beam simulation and optimization. We adopt a machine learning approach with a polarizable transverse deflecting cavity to reconstruct the multi-dimensional phase space of electron beam. By scanning the strength of the quadrupole magnets and the polarizations of the deflecting cavity, projections of the...
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. A Multi-Objective Genetic Algorithm (MOGA) has been implemented to optimise both the beam lifetime and the injection efficiency for off-axis injection. The simulations have been run on 5 machine error seeds, including...
The Electron-Ion Collider (EIC) is the next-generation accelerator facility to be built at the Brookhaven National Laboratory. To achieve EIC’s performance goals, an Energy Recovery Linac (ERL) cooler using Coherent electron Cooling (CeC) is designed to maintain the low emittance of the hadron beam. The ERL cooler requires high-current electron beams with low emittance and a uniform beam...
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 for multiple...
Abstract—A SCILAB Xcos model, developed using SCILAB software version 6.1.1, was implemented to simulate the on-axis radiation intensity of a helical undulator, (undulator parameter= 1, undulator wavelength 5cm, number of periods= 10, device length 0.6 m) with an electron beam (1, 2, & 3 GeV) and beam current as Ib = 3–6 × 10⁻⁶ Ampere. A numerical approach is utilized to perform the undulator...
The European Synchrotron Radiation Facility - Ex-tremely 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 Large Hadron Collider (LHC) features a collimation system that protects the machine against beam losses that may induce the loss of superconductivity in some exposed lattice magnets. Thus, optimal cleaning performance must be ensured at all times. The collimation system encompasses more than 100 collimators whose settings are organised in a well-defined transverse multi-stage hierarchy. A...
Following the LHC Injector Upgrade programme (LIU) there has been a gradual ramp-up of the intensity of LHC beams in the CERN Super Proton Synchrotron (SPS). This was initially hampered by vacuum issues in several critical components, such as RF cavities and kicker magnets, requiring extensive scrubbing campaigns to condition these components. This paper reviews the current status of the high...
In view of the unprecedented beam intensities expected in the High-Luminosity era of the Large Hadron Collider (HL-LHC), an upgrade of the LHC injection kickers (MKIs) is currently underway. This upgrade aims to mitigate excessive beam-induced heating of the MKIs and to limit resulting vacuum activity. The first MKI Cool was installed in the LHC during the Year End Technical Stop (YETS) in...
Every high-energy beam dump event at the Large Hadron Collider (LHC) is analysed to assess the performance of the machine protection systems and to identify anomalous behaviour. Analysing the loss pattern of nearly 4000 beam loss monitors, which depends on beam parameters and machine settings, can be time-consuming and requires expert knowledge. Therefore, an automated beam loss analysis tool...
The baseline design for the high-energy complex of a muon collider consists of a chain of pulsed synchrotrons spanning an energy range from 63 GeV to the target collision energy of 5 TeV. This chain incorporates both normal and hybrid synchrotrons, featuring a combination of fixed-field superconducting magnets and pulsed normal-conducting magnets. Initial optics designs for the chain of...
The compact ERL has been operated at the various beam optics as a test facility for industrial applications, such as the future EUV-FEL for a lithography. The short bunch length is the key for the high intensity SASE FEL therefore a tunable R56 of the arc optics is necessary for the bunch compression. We demonstrate the two kinds of arc optics: one is easy optics matching and another one is...
The Future Circular Collider, FCC-ee, is a proposed next generation electron-positron collider aiming to provide large luminosities at beam energies from 45.6 up to 182.5 GeV. This collider faces a major challenge to deliver the design performance in the presence of realistic lattice errors. A commissioning strategy has been developed including dedicated optics designs, efficient beam-based...
As new synchrotron light sources push for lower emittances, intra-beam scattering (IBS) becomes an increasingly more important factor in determining the final beam distribution properties. Because IBS depends strongly on beam energy, in the regime of ultra-low emittance rings, beam energy is a parameter to be optimized for best beam performance. In this report, we study the optimal beam energy...
Additive manufacturing is a now-powerful tool for the rapid prototyping and manufacturing of complex geometries. A proof-of-concept 433 MHz IH-DTL cavity was constructed for direct additive manufacturing of linear accelerator components. The CFD analysis of the initially designed cooling for the drift tube revealed a design with insufficient heat dissipation; this can lead to thermal...
PLS-II has been faithfully fulfilling its role for 13 years since it launched its user service in 2012. As the 4GSR project is currently underway in South Korea, upgrading PLS-II to PLS-III is expected to take a significant amount of time. Therefore, how PLS-II can be optimized and used well over a significant time in the future is an important question. In this presentation, we present how to...
At the Pohang Accelerator Laboratory X-ray Free-Electron Laser (PAL-XFEL), a scheme for generating attosecond XFEL pulses in the soft X-ray undulator line is under development using the Enhanced Self-Amplified Spontaneous Emission (E-SASE) method with an external laser pulse. To account for the slippage effect in the soft X-ray region, a mid-wavelength infrared (IR) laser pulse will be...
The pulse duration of the X-ray free-electron laser (XFEL) relies on the pulse duration of the electron bunch. The energy distribution of the electron bunch can be manipulated by using the laser heater in the purpose of generating attosecond pulse duration electron bunch current profile. Therefore, the resultant electron bunch current profile after the bunch compressor chicanes is programmable...
A recent simulation study demonstrated the potential to achieve high 4D-emittance using an emittance exchange (EEX) beamline integrated within a photoinjector. This EEX beamline enabled to achieve the final normalized longitudinal emittance of 0.44 micron, which corresponds to rms bunch length of 7micron and energy spread of 32keV. These results are noteworthy for a 60-MeV photoinjector...
The measurement of electron Yukawa coupling, ye, via direct s-channel Higgs production at ~125 GeV centre-of-mass (CM) energy, is significantly facilitated at the FCC-ee if the CM energy spread can be reduced to a level comparable to the natural width of Higgs boson, ΓH = 4.1 MeV. Achieving this reduction is possible through the “monochromatization” concept, which...
The increased beam intensity during the HL-LHC era is expected to impose tight margins on the operation of the LHC RF system. The larger momentum spread from the injectors together with twice the bunch charge calls for a higher RF voltage at injection to avoid beam losses. However, the peak RF power due to the increased beam loading must be kept below the saturation level of the klystrons....
The PITZ facility at DESY in Zeuthen has demonstrated the first operational high peak and average power THz self-amplified spontaneous emission (SASE) free electron laser (FEL). The current setup displays the onset of saturation at a central frequency of 3THz using a 3.5m long LCLS-I undulator. However, the THz user community has expressed the need for carrier-envelope phase (CEP) stability...
Spin motion in an accelerator is governed by the Thomas-Bargmann-Michel-Telegdi (T-BMT) equation, which describes how electromagnetic fields affect a particle’s spin. Although the fields experienced by a particle are determined by its orbital trajectory through a magnet, there is no analytical solution to the T-BMT equation, even for simple elements like dipoles and quadrupoles. However, if...
Orbit alignment plays an important role in free-electron laser (FEL) facilities, particularly in the collimation section, where multipoles are strategically positioned near the collimators as part of the specialized optics design. At the European XFEL, a strong dependence of lasing performance on the orbit in the collimation section has been observed. This study focuses on calibrating the...
For more than 40 years synchrotron-based x-ray sources as well as free-electron lasers based on linear accelerators have been widely used in materials science, spectroscopy, crystallography, research of fast processes, medicine, molecular biology and biochemistry, medicine, and other applied and scientific tasks. Two 4th generation synchrotron light sources will be in Russia soon. One of it is...
PERLE (Powerful Energy Recovery LINAC for Experiment) is a high-power Energy Recovery LINAC (ERL) facility with 20 mA beam current and 500 MeV final energy, initially operating at 250 MeV, through three accelerating and three decelerating passes. Operating in the high-power regime of 10 MW brings challenges in beam steering and control. This work studies optics misalignments and their impact...
The user operation of the Extremely Brilliant Source (EBS) since August 2020 has opened a new era of high energy fourth generation synchrotron radiation light sources. During the following four years of operation, the EBS accelerator has sustained user operation with high availability, reliability, and stability, and has continued to improve beam performance by reducing injection...
Off-momentum losses at the start of the LHC acceleration ramp in proton runs gave rise to multiple beam dumps by exceeding Beam Loss Monitor (BLM) thresholds in the momentum cleaning insertion (IR3). Accurately estimating the power deposition profiles in IR3 is necessary to determine where BLM thresholds can be optimized, thereby reducing unnecessary beam dumps and improving machine...
The Advanced Sources and Detectors (ASD) electron linear induction accelerator, nicknamed Scorpius, will perform multi-pulse radiography for sub-critical experiments of dynamic special nuclear material. Major technical systems include the Solid-State Pulsed Power (SSPP), Injector, Accelerator, Downstream Transport (DST) and Detector. SSPP powers both the Injector and Accelerator and provides...
In preparation for the 2026 Update of the European Strategy for Particle Physics, various options for a future circular hadron collider, FCC-hh, are being proposed. Here, we discuss a few operational scenarios spanning c.m. energies from about 70 to 120 TeV, which correspond to arc dipole field strengths ranging from 12 to 20 T. We present the respective integrated luminosity forecasts,...
The CERN-SPS beam dump system (SBDS) is equipped with a dilution kicker system, the so-called MKDH. During the 2022 and 2023 beam commissioning, the vacuum rise in the MKDH became a concern for reaching the anticipated higher beam intensities. Dedicated conditioning of the SPS kickers enabled successful attainment of High-Luminosity (HL) beam intensities during 2024 operation. However, the...
A 90-mA and 52.5-keV negative hydrogen ion (H⁻ ion) beam has been extracted from the J-PARC Radio Frequency (RF) H⁻ ion source. The 90-mA beam phase-space distribution at the entrance of the Radio Frequency Quadrupole (RFQ) cavity was measured at the test stand. Compared with the 60-mA beam condition for the present J-PARC user operation, reasonable increase in the operation parameters (the RF...
The Super Tau-Charm Facility (STCF), proposed by the University of Science and Technology of China, represents the next generation of electron-positron colliders. With a target luminosity exceeding 5×10^34 cm-2s-1, the STCF aims to achieve approximately two orders of magnitude higher luminosity compared to the current BEPCII. To reach such high luminosity, a combination of large Piwinski angle...
To avoid unacceptable proton emittance growth via beam-beam interaction, the EIC electron storage ring (ESR) requires very stringent tolerances for beam position and size stability at the interaction point. These tolerances imply tight specifications for several accelerator systems, including magnet power supplies (PS). While the magnetic field ripple requirements are most stringent at the...
A 100-MeV proton linac has been operated for over 10 years at KOMAC and used for proton beam services. We are planning to upgrade the linac energy to 200-MeV. By increasing the linac beam energy, we expect the machine to be capable of serving wider application fields including space radiation tests of semiconductor devices and material tests by using high-energy neutrons generated by...
The utilization of plasma devices in beam transport is slowly being accepted as a worthy alternative thanks to its potential in maintaining or even reducing particle beams emittance but also for its compactness which supplements the recent advances in compact laser plasma acceleration systems. However, their use can go beyond the substitution of magnets. In this work, the utilization of a low...
High polarization is required for both electron and ion beams for the Electron Ion Collider (EIC). To preserve polarization in the hadron storage ring (HSR), several full Siberian snakes will be employed. To reduce the depolarizing resonance strength and high luminosity, ion beams will be cooled at HSR injection. Extensive simulations have been done to check polarization levels when beam...
The Future Circular Collider (FCC-ee) at CERN requires a betatron and momentum collimation system for reducing particle backgrounds in the detectors, and for protecting the machine in case of excessive beam losses. The system is composed of primary and secondary collimators, which will be housed in one of the technical insertions of the 91 km ring. In this paper, we present a first assessment...
The Canadian Light Source, currently, does not correct beta beating. However, it has been known for some time that insertion device correlated vertical beam size changes can cause large reduction in flux at the VEPSERS beamline. In this work we discuss our preliminary explorations to control the vertical beam size, correct beta beating and reduce the flux variation for the VESPERS beamline. We...
The Cool Copper Collider (C3) is a proposed electron-positron linear-collider Higgs factory which leverages the high accelerating gradient achieved when a normal conducting copper cavity is cryogenically cooled with liquid nitrogen. To produce suitably short, flat, low emittance electron and positron beams, prior to the main Linac, a damping ring and bunch compressor are employed. In this...
Plasma lenses are a compact way to transport an electron beam, since they offer strong focusing (kT/m) in both planes simultaneously. This becomes particularly important for highly diverging beams with a large energy spread such as those typically originating from plasma accelerators. The lens presented here is an active nonlinear plasma lens, with controlled nonlinearity purposely introduced...
The Future Circular Collider e+e- (FCC-ee) sets an unprecedented precision target for energy measurements. Resonant depolarization is the only method capable of meeting this ambitious goal. In this preliminary study, the resonant depolarization experiment has been simulated using nonlinear spin tracking to model the intricate spin dynamics involved. A detailed measurement plan for FCC-ee has...
A new high-intensity Beam Dump Facility (BDF), hosting the SHiP (Search of Hidden Particles) experiment, is set to begin operation in CERN’s North Area (NA) in Run 4. To meet its physics goals, SHiP aims at accumulating 4$\times$10$^{19}$ protons on target per year, which will require approximately 10$^6$ high intensity cycles from the SPS with $4.2\times10^{13}$ p$^+$ per cycle (as...
Kyoto University Free Electron Laser (KU-FEL) has been developed for promoting energy related researches in Institute of Advanced Energy, Kyoto University. Currently two accelerator based infrared light sources, a mid-infrared FEL (MIR-FEL) and THz coherent undulator radiation (THz-CUR) are available. MIR-FEL covers the wavelength region from 3.4 to 26 micro-m and THz-CUR covers the frequency...
Cavity-based XFEL - CBXFEL - is an ongoing experiment at SLAC Accelerator National Laboratory. It utilizes first seven LCLS hard x-ray undulators, wrapped into a rectangular Bragg cavity. CBXFEL is expected to operate at 9.831 keV, and serve as a proof-of-principle device for future large scale cavity-based systems. We report on the recent status and preliminary experimental results.
A new lattice configuration is being developed for a compact,isochronous ring for the ISRS project, as an innovative spectrometer at HiE-ISOLDE. The design incorporates ten combined-function, canted cosine-theta (CCT) superconducting magnets, enabling the ring to fit within a constrained 5x5 meter hall space. This design presents significant challenges, particularly in accommodating the...
A 10 TeV center-of-mass muon collider could serve as a next-generation high-energy lepton collider with substantial physics potential while offering a more compact footprint than other proposed machines. However, this collider presents unique challenges, largely due to the short lifetime of muons and their decay products. Specifically, the collider ring requires specialized designs to protect...
Significant progress has been made on the lattice design for the next-generation Australian Synchrotron storage ring. The lattice has changed from a 7BA to a 6BA to improve the suppression of higher-order resonance driving terms due to sextupoles. Octupole magnets were introduced in non-dispersive regions to control amplitude-dependent tune shifts. The parameters of the unit cell were...
The 2023 P5 report and recent long-term planning efforts in high-energy physics emphasize the need for a future discovery collider operating at 10 TeV parton center-of-momentum (pCM). A promising candidate is a wakefield-based linear collider, offering various beam options. While conventional electron-positron collisions using flat beams are preferred, challenges with accelerating such beams...
The Project Management Office (PMO) at FAIR ensures the implementation and strategic steering of this complex international project. Its tasks include coordinating organizational aspects, managing budgets, schedules, and risks, and integrating international contributions. The PMO aligns project execution with strategic goals. A PMO is essential due to the project’s scale and complexity. It...
Interactions of dust grains with the LHC beams cause particle losses that can trigger pre-mature beam aborts and even cause quenches of superconducting magnets. While the simulated dynamics and ionisation of dust grains inside the proton beam are in good agreement with measured beam-loss data, a direct measurement of the dust trajectory is currently not possible. A method was developed to...
Electron-positron ERL colliders at the Z pole are proposed as a sustainability near future collider.The components are similar to the ILC accelerator, which consists of the linac with the 9 cell superconducting cavities, the 5 GeV damping ring, the beam delivery system for the final focus, and the electron and positron injectors. The recirculation loop is added to the ERL scheme. To fit it in...
Gamma-ray induced nuclear physics experiments rely on good signal-to-noise ratio, requiring accurate rejection of detector background. One source of this background is the interaction of cosmic rays with nuclear detectors. The Duke High Intensity Gamma-ray Source (HIGS) is typically operated in quasi-CW mode, requiring background measurements to be conducted independently of data production...
The lepton Future Circular Collider (FCC-ee) at CERN provides electron-positron collisions at four interaction points (IPs) along a 91 km ring, with beam energies spanning from 45.6 GeV (Z pole) to 182.5 GeV (ttbar threshold). The radiation showers produced by these collisions can reach sensitive components of the surrounding machine elements, possibly affecting their performance and lifetime....
In the period from October 2021 to August 2024, a cavity was developed for the 3rd harmonic system of PETRA IV. The development has progressed so far that a complete CAD model already exists. The cavity design has been reviewed by an external expert and approved. The project team is now working on clarifying the final details of the design and preparing all the technical documentation for the...
Optical Stochastic Cooling (OSC) is a state-of-the-art beam cooling technology first demonstrated in 2021 at the IOTA storage ring at Fermilab's FAST facility. A second phase of the research program is planned to run in 2025 and will incorporate an optical amplifier to enable increased cooling rates and greater operational flexibility. In addition to beam cooling, an OSC system can be...
The compact ERL (cERL) is a test accelerator operating at KEK. Its main purposes are to develop key technologies related to energy-recovery linacs and high-current superconducting accelerators for industrial applications. An important goal of our activity is to realize a high power FEL source for future EUV lithography.
In recent years, we have been working on demonstrating high current beam...
The KOMAC (Korea Multi-purpose Accelerator Complex)of the KAERI (Korea Atomic Energy Research Institute) has been operating 1.7 MV and 3 MV Tandem accelerators for many years. Recently, in the fields of cultural heritage research and semiconductor device development, there have been strong demands from users for precise composition analysis and large-area & uniform irradiation of proton beam...
The dynamic aperture is a key metric for assessing the stable phase space of particle accelerators and evaluating their overall stability. However, in highly damped accelerators such as high-energy electron synchrotrons like the Future Circular Collider (FCC-ee), the rapid amplitude variation of tracked particles over a few turns introduces significant sensitivity to initial conditions and the...
The scheme with quadrupole lenses is presented for realization relativistic strophotron type Free electron laser. Equations of motion are solved and trajectories are found. It is shown, that movement of electrons in presented scheme is stable in both transverse directions.
The accelerator and free-electron laser (FEL) laboratory at the University of Hawai’i at Manoa (UHM), established by John Madey, has been in standby since his passing in 2016, with operations further paused during the pandemic. Recent efforts aim to recommission the facility, which includes a thermionic gun, an S-band linear accelerator reaching 45 MeV, and a Mark III undulator FEL oscillator...
The Super Tau-Charm Facility (STCF) is a new generation of electron-positron colliders being planned with a design center of mass energy of 2-7 GeV. In the concept design, the positrons produced by electron targeting are accelerated to an energy of 200MeV by three large-aperture accelerating structures, and then to 3.5GeV by several conventional accelerating structures. The aperture of...
The Relativistic Heavy Ion Collider (RHIC) Run 24 was 27 weeks, operating with collisions at the STAR and sPHENIX detectors. The secondary running mode was gold at 100 GeV/u, where there was 3 weeks of operation. The goals of this run were to: reach an intensity of 1.8e9 ions/bunch and fully commission the 56 MHz cavity, ensure sPHENIX systems are ready for Run25,and deliver 1-2e9 minimum bias...
Here I will showcase the advanced precision instrumentations involved at the Veritas beamline dedicated to high resolution soft X-ray resonant inelastic X-ray scattering (RIXS) experiments. Following this, I will unveil the unique science cases one can attempt here.
In 2024 DAFNE successfully completed the data delivery for the SIDDHARTA-2 detector largely exceeding the integrated luminosity requested by the experiment. This has allowed allocating the machine time for several dedicated beam dynamics experiments useful for both the collider characterization and for the design of future electron-positron colliders based on the crab waist collision concept.
TWOCRYST is a machine test designed to demonstrate the feasibility of an in-vacuum fixed-target experiment for the first direct measurement of the magnetic and electric dipole moments of short-lived charm baryons. This setup exploits crystal channeling using two bent crystals. The first one is similar to the existing crystals used in the LHC for beam collimation, deflecting the beam halo...
A circular waveguide lined with a thin dielectric layer enables electron bunches propagating within the structure to radiate light in the (sub-)THz regime. In this work, we perform simulations of low-energy electron beams traversing extended waveguides to analyze the dynamics of beam bunching and lasing within the structure. By exploring the free-electron laser (FEL) process in this context,...
Bent crystal collimators (BCC) are a promising technology for halo collimation in high-power synchrotrons. To investigate their performance, a BCC module has been integrated into G4PyORBIT, leveraging Geant4's precise modeling of crystal channeling and PyORBIT's beam dynamics simulation capabilities. This study applies the tool to the rapid cycling synchrotron (RCS) at the China Spallation...
Ion profile monitors (IPMs) provide a non-destructive means of measuring the transverse beam size of a passing ion beam in a particle accelerator. The Alternating Gradient Synchrotron (AGS) at Brookhaven National Lab is equipped with two types of IPMs: ion-collecting and electron-collecting. While ion-collecting IPMs are susceptible to significant distortions in the measured beam size due to...
The nutrinos from Stored Muons (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...
PAL-XFEL (Pohang Accelerator Laboratory X-ray Free Electron Laser) is a facility that generates high-brightness FEL for users to perform the FEL-based sciences. Currently hard and soft X-ray (HX/SX) beamlines are operational, but the parallel operation can be done with less than 60 Hz using a single electron bunch from the electron injector. Therefore, for the user service with maximum...
Beam based alignment (BBA) plays an important role in the commissioning of the light sources. To speed up the BBA, a BBA method using AC excitation, called fast BBA (FBBA), has been proposed and is tested in several existing light sources. In the FBBA, the beam orbit is sinusoidally modulated at around 10Hz by AC correctors, and the change in the beam response when a target quadrupole magnet...
Modern injection schemes for light sources seek to explore the full 6D phase space in order to find creative ways of top-up injection with minimal perturbation to the stored beam. The longitudinal injection scheme is considered for the SLS 2.0 storage ring and, hence, the longitudinal profile of the injected beam becomes highly relevant for the injection efficiency. We simulate possible ways...
We have started single electron storage experiments since 2021 at the UVSOR-Ⅲ storage ring with the aim of conducting fundamental research on electromagnetic radiation. At BL1U, which is a beamline dedicated to light source developments, we extracted undulator light in the UV wavelength range into the air and observed its intensity by a photomultiplier tube, as decreasing the electron beam...
We report the generation of single spike hard x-ray pulses at the Linac Coherent Light Source enabled by temporal shaping of the photocathode laser. The pulses were produced with typical pulse energies of 10 uJ and full-width at half-maximum spectral bandwidths averaging 30 eV, corresponding to a 60 attosecond Fourier-limited pulse duration. These pulses open new doors in...
The Swiss Light Source, SLS, storage ring has been rebuilt as SLS2.0, to improve the radiation brightness by about two orders of magnitude. All components of the storage ring lattice and its supporting infrastructure are newly constructed and were installed during a 15-month shutdown that began in October 2023. The linac and booster synchrotron received only small modifications with the...
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 synchrotron SOLEIL is France's 2.75 GeV third-generation synchrotron light source and serves as a cutting-edge research laboratory dedicated to advanced experimental techniques for matter analysis at the atomic scale. It also functions as a service platform accessible to both scientific and industrial communities. This abstract highlights the performance of the accelerators, which deliver...
Transmission Electron Microscopes (TEM) require high voltage DC electron sources, which can quickly grow in size and cost at the higher energies required for standard TEM imaging. We present the progress on a low cost, compact solid-state-driven RF linac to replace high power electron guns in micro-crystal electron diffraction setups. The system accelerates electrons to 50 keV electrons with a...
With the adoption of multi-bend achromat lattices and the aim for diffraction limit, the state-of-the-art light sources are approaching a point where their emittance becomes so small that the effects of space charge can no longer be ignored. Space charge produces a significant betatron tune spread that affects many aspects of beam dynamics: single particle dynamics to collective beam...
Highly polarized MeV gamma rays, produced by Laser Compton Scattered (LCS) of a polarized laser with an electron beam, offer a unique probe for basic and applied physics research. As the polarization characteristics of these gamma rays vary with the position of the beam cross section, it is essential to understand the polarization properties when using polarized gamma rays * . However,...
The RHIC spin flipper consists of interleaved AC dipoles and DC dipoles to achieve high spin-flip efficiency at high energies. The sophisticated design aims to minimize beam oscillations outside the spin flipper. For spin tune measurements, the requirements are simpler. It has been shown that by using AC dipoles, one can sweep the AC dipole tune across the spin tune to depolarize the beam. By...
SPS-II was designed for low emittance storage ring with compact Double-Triple Bend Achromat (DTBA) cell. To ensure sufficient machine performance, realistic machine imperfections were simulated and incorporated into the optimization process.Thus the lattice solutions were made robust against imperfections, thereby reducing the machine's sensitivity. Solution with sufficient dynamic aperture...
This paper presents comprehensive start-to-end commissioning simulations for the SOLEIL II storage ring upgrade, demonstrating the feasibility of achieving an ultra-low emittance of 84 pm-rad at 2.75 GeV. We detail a multi-step correction strategy addressing challenges posed by the dense magnet arrangement and limited number of BPMs and correctors. Our simulations encompass first turn...
This paper presents statistical uncertainty studies on data analysis methods employed for the alignment of induction voltage adder (IVA) cell magnets in the Scorpius Injector. The Stretched Wire Alignment Technique (SWAT) was utilized to precisely locate and align the magnetic axis of beamline solenoid magnets. A current pulse with duration of approximately 100 µs was propagated through a...
LumiBelle2 is a fast luminosity monitor used for beam parameter tuning and feedback at the interaction point of SuperKEKB. It uses sCVD diamond detectors placed in both the electron and positron rings to measure the rates of single bremsstrahlung events. Luminosity signals are provided both for averaging all bunches and for each bunch crossing at 1 Hz. The averaged luminosity signal over all...
Recent years have seen growing interest within the laser particle acceleration community in laser sources operating at wavelengths substantially longer than the ~1 µm typical of present-day facilities. This renewed focus is fueled by recent advancements in powerful mid- and long-wave infrared (M/LWIR) laser sources. While fundamental advantages, such as the λ2-scaling of ponderomotive...
The construction of the new FAIR heavy ion accelerator facility at GSI is progressing well. With the start of installation of SIS100 an important new milestone in project execusion has been reached. SIS100 is the first superconducting, fast ramped synchrotron with special design features dedicated to the acceleration of high intensity, low charge state heavy ions. The full performance of the...
SIRIUS is a state-of-the-art Synchrotron Light Source Facility, featuring a 3 GeV electron storage ring with a 518 m circumference and 250 pm.rad emittance. Built and operated by the Brazilian Synchrotron Light Laboratory (LNLS) in Campinas, Brazil, SIRIUS has undergone significant upgrades over the past year. These enhancements include the installation of superconducting RF cavities,...
PERLE (Powerful Energy Recovery Linac for Experiments) is a three-turn, high power Energy Recovery Linac under construction at IJCLab, France. It emerged from the design of the LHEC and FCC-eh and will serve as a hub for the validation of several technical choices and exploration of a broad range of accelerator phenomena in an unexplored operational power regime (up to 10 MW in its final...
DELTA, a 1,5 GeV electron storage ring facility operated by the TU Dortmund University in Germany celebrated its 30th anniversary in autumn 2024. During its time in operation, the facility has been continuously developed in order to provide synchrotron radiation (SR) users with the most reliable and attractive radiation source possible. This includes the continuous improvement of electron beam...
FLUTE (Ferninfrarot Linac- Und Test-Experiment) is a new compact versatile linear accelerator at KIT. Its main goal is to serve as a platform for a variety of accelerator studies as well as a generation of strong ultra-short THz pulses for photon science. Also it will be used as an injector for a Very Large Acceptance compact Storage Ring (VLA-cSR) which will be realized at KIT in the...
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...
SILA (Synchrotron Laser) is a project of the National Research Center Kurchatov Institute (NRC KI) planned for the period 2022-2033. It is aimed at creating a 4th generation synchrotron radiation source and a free electron laser. The storage ring is divided into 40 periods, the perimeter (SR) is 1103 m, the electron energy is 6 GeV, the horizontal emittance is 70 pm∙rad. The free electron...
The VEPP-5 injection complex was put into operation as a source of electronic and positron beams for the VEPP-2000 and VEPP-4M colliders at the end of 2016. To date, an operating energy of 430 MeV and a positron accumulation rate of 3.5 nC/s have been achieved. Options for improving the complex for working with promising installations are being considered. The latest results and prospects of...
The study of beam-cavity interaction is an essential step towards achieving the design objectives of high-intensity storage rings, particularly in the rapidly advancing fourth generation of synchrotron light sources, which rely on the strategy of bunch lengthening with harmonic cavities. Assessing the effectiveness of harmonic cavities typically requires self-consistently solving bunch...
The autonomous alignment and optimization of syn-chrotron beamlines pose significant challenges. Tradi-tionally, manual alignment is a time-consuming and ex-perience-dependent process, often requiring extensive diagnostic efforts and data collection. With the construc-tion of the Hefei Advanced Light Facility (HALF) under-way, the development of a virtual platform for beamlines will be an...
PETRA IV is the storage ring light source currently under design at DESY in Germany. The baseline injector is a 6-GeV synchrotron DESY IV, an upgrade to the existing injector DESY II. Even if the project matures DESY IV's engineering design, we studied the intensity limit of DESY II, whose aim was to increase the single bunch charge to more than 10 nC suitable for the on-axis swap-out...
In this study, we use tracking simulation to investigate the feasibility of synchrotron phase space injection for the electron storage ring (ESR). Our simulation model includes both beam-beam interaction and the nonlinearity of ESR lattice. The sensitivity of the particle loss against various injection parameters will be presented.
The H6BA lattice is now considered as the baseline design for PETRA-IV light source. It is required that the ring can be operated with and without damping wigglers, resulting in two sets of natural equilibrium beam parameters. This paper analyzes the single-bunch effects due to impedance in the H6BA lattice of PETRA-IV. We will show the influence of the impedance on the electron beam in both...
This work examines the dominant coherent head-tail type (< x-z >) instabilities in the vertical plane of the FCC-ee collider, focusing on a mode analysis method with the Circulant Matrix Model (CMM) to assess instability mechanisms under the influence of beam-beam effects and transverse wakefields. While the impact of vertical plane instabilities have been already studied, different...
We propose a phase jump method to improve the electron beam conversion efficiency in FEL oscillator. A fast phase shifter is put between two undulator segments to kick the phase of the electron beam at saturation. The theoretical and simulation results are given based on FELiChEM which is built in Hefei. They indicate that a phase jump value of approximately π at saturation can significantly...
Laser ion sources can produce a very high pulsed beam current, but still more than 90% of the beam is lost. In order to further increase the beam current of the laser ion source, this study installed a solenoid in the ion source target chamber and investigated the relationship between the solenoid and the generated beam current.
PAL-XFEL comprises two lines: Hard X-ray (HX) line for 2.5-15 keV FEL and Soft X-ray (SX) line for 0.25~1.1 keV FEL. Both lines share accelerator sections L1, L2, L3A, and two Bunch Compressors (BCs). The electron bunch is accelerated to 2.8 GeV and compressed to a peak current of 400-500A using accelerators and two BCs, then it is directed into either the HX or SX line at the branch line....
The surface muon beamline at J-PARC delivers high-intensity muon beams essential for cutting-edge materials science research. However, positron contamination significantly impacts spectrometer measurements as a major source of noise. This study employs the G4 beamline Monte Carlo simulation toolkit to investigate positron contamination and develop mitigation strategies. Simulations track...
We have been studying about a pre-bunched FEL in the THz region. In the pre-bunched FEL, the electron bunches being compressed shorter than the oscillation laser wavelength, it is expected that we can generate short-pulse THz laser pulses with high peak intensity. A broadband spectrum and high-intensity characteristics, which cannot be realized by conventional FEL, are expected. The...
Understanding the characteristics of the beam source is crucial for designing optimal beamline optics. During the construction of PAL-XFEL, simulation studies on the characteristics of the XFEL beam source were conducted in advance to aid in the design of beamline optics and experimental instruments. However, since the facility began providing user services in 2017, the performance of PAL-XFEL...
As proposed in Ref[1], a fully coherent synchrotron light source requires a high-current, low-emittance storage ring with very short damping time to deliver a high-quality beam for the bypass line, ultimately producing high average power EUV radiation. The initial design adopts 8 TBA (Triple Bend Achromat) cells, with four cells forming one superperiod. The straight sections on either side of...
Recent progress on the experiments of Inverse Compton Scattering (ICS) at Brookhaven National Laboratory Accelerator Test Facility (BNL ATF) is introduced. Nominal e-beam parameters utilized are electron beam energy of 70 MeV, charge per pulse of 0.5 nC with normalized emittance of 2 mm mrad. Use of long wavelength TW CO2 laser, and short wavelength Nd: YAG or Ti: Sapphire lasers allows us to...
The Hefei Advanced Light Facility (HALF) is a diffraction-limited storage ring light source. The HALF storage ring lattice has relatively long damping times, which can result in substantial variations in beam emittance when the gaps of insertion devices change. In this paper, we study different ways to suppress the emittance variation of the HALF storage ring, including the usage of damping...
X-ray vortices carrying tunable Orbital Angular Momentum (OAM) are an emerging tool for X-ray characterization technology. However, in contrast to the generation of vortex beams in the visible wavelength region, the generation of X-ray vortices in a controlled manner has proved challenging. Here, we demonstrate an X-ray free-electron laser oscillator (XFELO) can adjust only the kinetic energy...
Currently, the choice between the standard higher-order multi-bend achromat (MBA) and the hybrid multi-bend achromat (h-MBA) lattices for new 4th-generation storage rings is a difficult decision. This report presents a systematic view of the standard MBA performance when the lattice is scaled to different lengths and periodicities. At the core of the standard MBA is the unit cell, the optics...
A permanently running energy measurement based on resonant spin depolarization of the electron beam has been implemented at BESSY II for several years.
In order to move towards long-term energy stability and to be able to use the method for different applications, for example the determination of the momentum compaction factor, the present measurement time of almost four hours should be...
THz sources are typically very limited in power, making high-power sources scarce. One of the most promising THz sources are the Free Electron Lasers (FELs), which can generate high-power THz radiation using an undulator structure. Undulator radiation is an incoherent synchrotron spontaneous emission whose energy is proportional to the number of particles in the beam (𝑁). By longitudinally...
The electron-positron Future Circular Collider (FCC-ee) is designed to operate at four energies, from 45.6 GeV to 182.5 GeV. At such energy levels, the circulating beam loses a significant fraction of its energy via synchrotron radiation. As a single RF insertion is foreseen in the ring, large closed-orbit shifts featuring a typical sawtooth pattern and optics distortions are induced. This in...
VEPP-2000 electron-positron collider operating in the beam energy range of 150-1000 MeV is the only machine originally designed to exploit Round Beams Concept which results in significant beam-beam limit enhancement. After long shutdown for injection chain upgrade VEPP-2000 resumed data taking with luminosity limited only by beam-beam effects.
Thanks to extensive and thorough machine tuning...
At HZB / BESSY the first in-vacuum APPLE II undulator is under construction. The design includes three magnet arrays for each of the four magnet rows for an efficient force compensation. The support and drive system has been delivered and the specification of the magnets has been finished. All magnet pairs are soldered and the magnet pairs are clamped into the keepers. Central and compensating...
Fixed Field Accelerators (FFAs) are a promising candidate for future high intensity machines such as ISIS-II. It follows that the largely unexplored topic of coherent transverse beam instabilities in these machines is of increasing importance. Transverse instabilities, such as head-tail, can be mitigated in synchrotrons by adjusting the chromaticity appropriately. However, in scaling FFAs,...
High-brightness and high-average current electron sources with excellent beam quality hold significant potential for applications in fields such as ultrafast electron diffraction (UED), free-electron lasers (FELs), and energy recovery linacs (ERLs). However, when the electron beam is initially generated, it typically exhibits large energy spread, beam size, and relatively low energy. During...
The purpose of this paper is evaluating vibration status for cooling water pump system in TPS. The utility systems operate continuously since TPS commission in 2014. The predictive maintenance based on vibration level and spectrum became more important, especially for those unstoppable operate water pump systems. The vibration monitoring system started to construct in 2017 and upgraded in...
The insertion devices (IDs) can affect the electron beam quality of storage ring light source. We investigate how the IDs in Hefei Light Source (HLS) affect the linear and nonlinear beam dynamics. We use the kick map approach to simulate the IDs fields. To correct the linear optics perturbation due to the IDs, we use the adjacent quadrupoles to compensate the beta functions beating. We...
On July 2nd 2025 after 31 years of serving the user community with excellent results will start the removal of the Italian third generation synchrotron light source Elettra to be replaced by Elettra 2.0 a fourth-generation synchrotron light source. The Elettra 2.0 project is in full development and being a diffraction limited light source will provide ultra-high brilliance and coherence to the...
The goal of the ESSnuSB project is to precisely measure neutrino Charge-Parity Violation (CPV). The construction of the European Spallation Source, ESS, represents an outstanding opportunity for such project to take place. ESSnuSB has been funded from EU in the framework of H2020 (2018-2022) and Horizon Europe (2023-2026) to make feasibility studies. The aim of the first phase was to...
The field of ultrafast science has seen substantial growth over the past decade. High-power, ultrafast free-electron lasers (FELs) have become essential tools across various scientific disciplines, including physics, chemistry, and biology. The shorter pulse durations enable enhanced temporal resolution in pump-probe experiments. This paper introduces methods for generating ultrafast seeded...
The synchrotron radiation generated by storage rings offers numerous advantages, including high stability, a broad photon energy range, and the capacity to support multiple users simultaneously. However, one notable limitation is its poor radiation coherence. Achieving coherent harmonic generation (CHG) in storage rings would not only significantly enhance the coherence of the emitted light...
We present the lattice design features and performance evaluation of the Korea-4GSR storage ring. This greenfield ring has a 4 GeV beam energy, an 800 m circumference, and 28 cells. A natural emittance of 62 pm is achieved through the implementation of four longitudinal-gradient bends and six reverse bends within the hybrid multi-bend achromat unit cell. The ring includes two high-beta...
Currently the HIAF Project at IMP has reached the construction phase. The BRing is one of the key systems of HIAF, which is used to capture, accumulate, accelerate and extract the heavy ion beam injected by iLinac. The quadrupole magnets in BRing have large aperture (Ф260&Ф180) , large axial length(the total length of the magnet is reached 1140mm) and high integration field uniformity...
SKIF (Russian acronym for Siberian Circular Photon Source) – fourth-generation light source under construction in Novosibirsk. Natural emittance (at zero beam current and absent betatron coupling) of the SKIF is 72 pm at 3 GeV beam energy and 476 m circumference. Only two families of sextupoles provide horizontal and vertical dynamic apertures of 12 mm and 3.5 mm, respectively, and energy...
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...
The field of Free-Electron Lasers (FELs) has matured, with advancements prioritizing high repetition rates, full coherence, and an expanded wavelength spectrum. This paper details the establishment of a high-repetition-rate Infrared Terahertz (IR-THz) Free-Electron Laser (FEL) facility at the Hefei Comprehensive National Science Center. This facility is strategically integrated with the...
A fixed-target experiment using two bent crystals is proposed to study the magnetic and electric dipole moments of short-lived charm baryons with unprecedented precision in the LHC. This will be achieved exploiting crystal channeling into a first crystal to extract the beam halo and then into a 7 cm long silicon crystal capable of inducing a measurable spin precession to the particles of...
The Large Hadron Collider (LHC) can operate with high intensity proton and heavy ion beams, both of which require a collimation system to ensure an efficient operation and to protect against damage to sensitive equipment along the ring. The crystal collimation scheme using bent silicon crystals as primary collimators was therefore introduced to improve the collimation efficiency for heavy...
The Electron-Ion Collider (EIC), to be constructed at Brookhaven National Laboratory, will collide polarized high-energy electron beams with polarized proton and ion beams, achieving luminosities of up to 1 × 10^34 cm^−2 s^−1 in the center-of-mass energy range of 20-140 GeV. The EIC consists of two storage rings: the Hadron Storage Ring (HSR) and the Electron Storage Ring (ESR). Given the...
The intrinsic emittance obtained from radio-frequency (RF) photoinjectors is notably reduced by increasing the launch field at the cathode. Moreover, cryogenic RF guns offer the possibility of producing stronger fields, due to the higher bulk conductivity, while lowering the mean transverse energy (MTE) of near-threshold photo electrons. Such devices thus constitute an ideal tool for driving...
The High Luminosity LHC (HL-LHC) project aims to increase the integrated luminosity of CERN’s Large Hadron Collider (LHC) over its exploitation era up to the end of 2041 by an order of magnitude compared to the initial LHC design value. This requires doubling the bunch intensity along with several other important changes to the LHC configuration. Dedicated beam experiments in the LHC and its...
The Accelerator Test Facility 2 (ATF2) serves as a critical platform for testing technologies and techniques aimed at advancing the next generation of linear colliders. The ATF2 is composed of a linear accelerator (LINAC), a damping ring, and an extraction line that includes a high-precision final focus system designed to achieve the small beam sizes necessary for future collider experiments....
Driven by an electron accelerator and equipped with an undulator, the free-electron laser (FEL) is known for its capability to produce x-ray pulses at unprecedented brightness. As of early 2025, five FEL facilities operate at wavelengths in the hard x-ray regime: European XFEL in Germany, LCLS in the USA, PAL-XFEL in Korea, SACLA in Japan and SwissFEL in Switzerland. The present work...
Laser-Assisted Charge Exchange (LACE) is being developed at the Spallation Neutron Source (SNS) as a potential replacement for injection foils, which are not expected to endure in the 10 MW beam power regime. Previous experimental demonstrations have achieved highly efficient charge exchange of H⁻ ions to protons for beam durations of up to microseconds. A refined method, capable of scaling to...
Experimental programs entrusted to the Franco-British EPURE facility require more and more flexibility with regard to the operation of different functioning points for our two Linear Induction Accelerators (LIA). In 2023, UPRX work (presented at IPAC'24) demonstrated our ability to control both reliability and repeatability of our first radiographic axis performances at high current (2.6 kA)....
Single-sextupole and single-octupole lattices "exhibit .. all the typical properties of more complicated mappings and dynamical issues"*, including horizontal resonances of all orders $N$ with island tunes $Q_I$. Here we develop resonance trajectory curves in the $(Q_x,Q_I)$ tune domain that represent unique fingerprints of simple or complex one-turn maps. Island tune spectra - vertical slices...
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...
Helmholtz Zentrum Berlin is engaged in the conceptual design of the BESSY III facility. The BESSY III storage ring will be a fourth generation synchrotron light source with an emittance of about 100 pm rad and an energy of 2.5 GeV. It will be equipped with advanced undulators to provide users with tailor-made light. So far cryogenic permanent magnet undulators, hybrid planar undulators and a...
A high electron current is often needed in modern electron accelerators. To achieve this, an energy chirp must be imposed on the bunch so the electrons will compress when they pass through a chicane. This energy chirp is usually imposed by accelerating the beam off-crest from the peak fields of RF cavities, which increases the total length and power requirements of the linear accelerator...
The ThomX Compact Compton Source comprises an electron linac, an electron storage ring and a Fabry-Perot cavity. The electrons interact with laser photons at the intersection of the storage ring and the Fabry-Perot cavity. The facility started its commissioning in 2021 and the first X-rays were observed in June 2023. The operation energy was increased from 50 MeV to 70 MeV in 2024. We present...
Determining Yukawa couplings of the Higgs boson is one of the most fundamental and outstanding measurements since its discovery. The FCC-ee, owing to its exceptionally high-integrated luminosity, offers the unique opportunity to measure the electron Yukawa coupling through s-channel Higgs production at 125 GeV centre-of-mass (CM) energy, provided that the CM energy spread can be reduced from...
The RF buncher used in the Los Alamos Neutron Science Center (LANSCE) Proton Storage Ring (PSR) is facing obsolescence of several critical parts that would prevent sustaining operations into 2050. The present RF buncher uses triodes for its cathode-follower configuration that are no longer produced, and because no similar tubes exist to replace these triodes, an alternate bunching system must...
In the era of the High-Luminosity Large Hadron Collider (HL-LHC), the main RF system will be limited in voltage and power on the injection plateau due to strong beam loading. At the same time, significant start-of ramp losses, that are originating from capture and flat bottom losses, are expected and can severely impact machine availability or even prevent the beam from reaching the collision...
Brookhaven's Accelerator Facilities Division provides users with access to cutting-edge research tools, including the Accelerator Test Facility (ATF) and the Ultrafast Electron Diffraction (UED) facility. The ATF features an RF photocathode electron LINAC, a femtosecond Ti:Sa laser, and a high-peak-power LWIR laser, all capable of synchronized or independent operation. These tools enable...
As an option to control the vertical emittance a beam shaker will be implemented at the planned upgrade of the synchrotron light source at DESY, Hamburg. We evaluate the electron beam dynamics for a simple sine-wave and a noise band excitation and present the expected equilibrium vertical emittances.
Accurate characterization of radiation pulse profiles is crucial for optimizing beam quality and enhancing experimental outcomes in Free Electron Laser (FEL) research. In this paper, we present a novel approach that employs machine learning techniques for real-time virtual diagnostics of FEL radiation pulses. Our advanced artificial intelligence (AI)-based diagnostic tool utilizes longitudinal...
A novel soft X-ray BPM (sXBPM) for high-power beams of synchrotron undulator radiation has been developed through a joint effort by BNL/NSLS-II and Stony Brook University. In this approach, custom-made multi-pixel GaAs detector arrays are positioned in the outer portions of the X-ray beam, with beam position inferred from the pixel photocurrents. The first R&D device was installed in the 23-ID...
Optical frequency comb (OFC) technology provides precise measurement tools for optical frequencies, leading to revolutionary changes in the field of optics.OFCs consist of a series of uniformly spaced spectral lines resembling the teeth of a comb, and they have found widespread applications in timing, precision spectroscopy, and fundamental physics.Extending this technology into the EUV to...
X-ray Laser Oscillator (XLO) is an ongoing project at SLAC National Accelerator Laboratory. The project aims to construct world's first population inversion x-ray laser, using LCLS XFEL as a pump. XLO also utilizes the multi-bunch mode of LCLS copper linac, and a Bragg cavity arranged in a bow-tie configuration. When built, XLO will be able to generate x-ray pulses of very high quality. In...
Xsuite is a comprehensive simulation toolkit for accelerator physics, with Xcoll serving as the dedicated module for collimation studies. These studies involve tracking particles through an accelerator and simulating their interactions with matter, taking into account non-linear elements and large betatron and off-momentum deviations. Particle-matter interactions can be modeled using an...
A new high precision measurement of the Y(1S)-meson rest mass is being carried out at the VEPP-4M collider using the KEDR detector. The resonant depolarization method with the laser polarimeter has been employed for the absolute calibration of the beam energy. In the paper resent status of the experiment is discussed.
