The Future Circular Collider electron-positron (FCC-ee) pre-injector complex demands high-performance RF accelerating structures to achieve reliable and efficient acceleration of beams up to 20 GeV. In this study, we describe an analytical approach to RF design for the traveling-wave (TW) structures including a pulse compression system to meet the rigorous specifications of the FCC-ee...
In this paper, we investigate the usage of advanced algorithms adapted for optimizing the design and operation of different linear accelerators (LINACs), notably the superconducting linac ALPI at INFN-LNL and the ANTHEM BNCT facility to be constructed at Caserta, Italy. Utilizing various intelligent algorithms and machine learning techniques such as Bayesian optimization, genetic algorithms,...
Nb$_3$Sn is the most promising alternative material for the future of superconducting radio-frequency (SRF) technology, steadily advancing towards practical applications. Having a critical temperature twice that of niobium, Nb$_3$Sn offers the potential for developing smaller, more powerful, and more efficient accelerators. We have designed a comprehensive study to synthesize and characterize...
Recent studies indicate the magnitude of an anomalous decrease in the resonant frequency, so-called frequency dip, near critical temperature of superconducting niobium cavities, Tc, correlates to the cavity quality factor, Q0, and impurities introduced into the superconducting niobium surfaces, such as nitrogen or oxygen. We measured frequency dips in both 644 MHz fundamental mode (FM) and...
Sample alignment in neutron scattering experiments is critical to ensuring high quality data for the users. This process typically involves a skilled operator or beamline scientist. Machine learning has been demonstrated as an effective tool for a wide range of automation tasks. RadiaSoft in particular has been developing ML tools for a range of accelerator applications including beamline...
In the field of accelerator physics, the quality of a particle beam is a multifaceted concept, encompassing characteristics like energy, current, profile, and pulse duration. Among these, the emittance and Twiss parameters—defining the size, shape, and orientation of the beam in phase space—serve as important indicators of beam quality. Prior studies have shown that carefully calibrated...
Circular mode beams are beams with non-zero angular momentum and strong inter-plane plane coupling. This coupling can be achieved in linear accelerators (linacs) through magnetization of electrons or ions at the source. Depending on the magnetization strength, the intrinsic eigenmode emittance ratio can be large, which produces intrinsic flatness. This flatness can either be converted to real...
Accelerator-based light sources require high brightness electron bunches to improve performance in exploring structure of matter. Higher acceleration gradient is the key to generate high brightness electron bunches and is more feasible with higher frequency and shorter pulse length electromagnetic wave according to previous empirical formulas. A tapered rectangle waveguide structure driven by...
In accelerator physics, radio-frequency (rf) systems play a pivotal role in particle beam acceleration and diagnostics. This work presents a graphical interface designed with Python for interaction with rf instruments, enabling efficient data acquisition, processing, and visualization. Leveraging advanced software tools, the system enables efficient management and analysis of rf data. This...
The performance of superconducting radiofrequency (SRF) cavities is critical to enabling the next generation of efficient high-energy particle accelerators. Recent developments have focused on altering the surface impurity profile through in-situ baking, furnace baking, and doping to introduce and diffuse beneficial impurities such as nitrogen, oxygen, and carbon. However, the precise role and...
The Virtual Pepper Pot (VPP) is a 4D transverse phase space measurement technique based on pepper-pot-like patterns that are generated by crossing each measured horizontal slit-based beamlet with all measured vertical slit-based beamlets. The VPP beam phase space distribution reconstruction and simulation are performed using the Beam Delivery Simulation (BDSIM) code, which is a Geant4 toolkit....
Superconducting Radio Frequency (SRF) technology is a proven solution for generating high-power electron beams (EB), suitable for tasks like purifying wastewater from challenging impurities such as Per- and polyfluoroalkyl substances (PFAS). This paper elaborates on effectiveness of EB treatment and outlines design considerations for a 1.3 GHz SRF linac operating at 5 MeV with an average beam...
Laser wakefield accelerator (LWFA) and plasma wakefield acceleration (PWFA) have attracted a wealth of research interests since they can provide an accelerating gradient of ~100 GV/m. Recently, a series of LWFA/PWFA external injection experiments are foreseen to be carried out based on the linear accelerator (LINAC) of Beijing Electron-Positron Collider II (BEPCII). We hereby present a design...
Electron beams with low emittance are vital for a wide range of accelerator-based applications, including free-electron lasers, Thomson scattering sources, and ultrafast electron diffraction. Superconducting Radio Frequency (SRF) photo-injectors can produce low-emittance electron beams, particularly in continuous wave (CW) operation. Among the various photo-emissive layers, bi-alkali...
As part of CERN's medical application research, a compact electrode system (< 30 cm) has been designed to facilitate low-current, multiparticle beam extraction and matching to a high-frequency RFQ. This study explores the innovative extraction system design and evaluates its simulation performance. Superfish (SF) and CST Studio Suite were employed to export the 2D and 3D electric field maps of...
Fundamental power couplers are utilized in SRF accelerators to transfer RF power from a source to the accelerating cavities. However, the issue of thermal heat load during high-power transmission in continuous wave (CW) mode operation poses a significant challenge for power couplers. To address this concern critical modifications have been implemented within the warm sections of the cERL...
We are developing a laser-driven ion accelerator aimed at downsizing heavy ion therapy devices. The ion beam produced by this accelerator exhibits low emittance(transverse emittance is approximately 10-3 π mm-mrad and longitudinal emittance is approximately 10-5 eV・s), with a very short pulse width (about picoseconds). As a result, the peak current reaches the kA level. However, explosive beam...
In-situ plasma processing is a promising technique to reduce field emission in superconducting radio-frequency cavities and thus maintain maximum accelerator performance for long-term operation. Continuous-wave accelerators such as FRIB are more challenging than pulsed accelerators due to relatively weak coupling (Qext = 2E6 to 1E7 for FRIB) via the fundamental power coupler (FPC). This...
Using 2D and 3D particle-core models, we thoroughly studied potential resonance interactions between particles and core in matched beams within complete periodic and double periodic channels. By keeping consistent geometrical structures and phase advances, we compared the Poincaré sections obtained from both models. The findings show that the differences between the models are negligible. This...
The Cornell High Pulsed Power Sample Host Cavity (CHPPSHC) is a new system designed to measure the superheating field of candidate superconducting RF (SRF) materials, giving insight into their operational limits. This system is designed to reach peak magnetic fields of up to 0.5 T in only a few microseconds, allowing us to achieve a pure magnetic field quench on the sample. We present an...
The generalized longitudinal strong focusing (GLSF) scheme is a potential approach for a steady-state mi-crobunching (SSMB) storage ring, leveraging the ultra-low vertical emittance in the storage ring. It achieves active vertical-longitudinal coupling through an inser-tion unit, further compressing bunch length from the hundreds of nanometers scale in the main ring to the nanometers scale,...
For experiments requiring the longitudinal shaping of the beam at the exit of an electron linear accelerators, it is crucial to infer the initial beam profile at the entrance of the linear accelerator and key parameters. After passing through the dispersion section of beam bunch compressor, and the high-frequency system, the electron beam will undergo modulation on the longitudinal density....
The objective of this research work is to design and develop laser-assisted thermal electron and hydrogen scattering, using theoretical model for elliptical and circular polarized laser. To develop the model, Volkov wave function for thermal case in elliptical and circular polarized laser field was designed and designed wave function is used to obtain S-matrix using Kroll-Watson approximation...
Future High Duty Cycle (HDC) operation scenarios of the European X-ray Free Electron Laser (EuXFEL) promise increased bunch repetition rate and photon delivery, at the cost of changing system requirements and moving away from the current mode of Short Pulse (SP) operation. To assess whether the third harmonic cryomodule design is also suitable for Long Pulse (LP) and Continuous Wave (CW)...
The high-repetition-rate infrared terahertz free-electron laser (IR-THz FEL) facility are progressing in the preliminary research stage, which can achieve the demand for a tunable, high-power-light source in the long wavelength spectrum and form a complementary structure of advantages with the Hefei Advanced Light Facility (HALF). In this paper, we present the design of a bunch compressor...
Linear accelerators with dispersive elements experience projected emittance growth due to coherent synchrotron radiation (CSR) effects which become relevant for highly compressed beams. Even though this is a widely known effect, conventional measurement techniques are not precise enough to resolve the multi-dimensional effects in detail, namely the different rotations of transverse phase space...
The SRF community has shown that introducing certain impurities into high-purity niobium can improve quality factors and accelerating gradients. We question why some impurities improve RF performance while others hinder it. The purpose of this study is to characterize the impurities of niobium coupons with a low residual resistance ratio (RRR) and correlate these impurities with the RF...
The linear accelerator at the Facility for Rare Isotope Beams (FRIB) at Michigan State University uses a thin liquid Lithium film for charge stripping of high-intensity heavy ion beams. Energy straggling of the beam in the non-uniform Lithium film affects the energy distribution in the beam. This can lead to non-linear “tails” in the longitudinal phase-space beam distribution after bunching at...
This paper describes the physical design of one linac injector for the proton/heavy ion synchrotron, which is under construction for Xi’an 200 MeV Proton Application Facility(XiPAF) heavy ion upgrading project. A heavy ion linac injector will be constructed close to the existing proton linac injector. The heavy ion injector consists of one electron cyclotron resonance(ECR) source, one low...
Transverse Deflecting Structures (TDS) are commonly used in Free Electron Laser (FEL) facilities for the measurement of longitudinal information of electron beam, including bunch length, temporal distribution, slice emittance, etc. Shenzhen Superconducting Soft-X-ray Free Electron Laser (S3FEL) is a high-repetition-rate FEL recently proposed for scientific research and applications. In S3FEL,...
This work is part of the development study of a linac injector for hadron therapy with carbon ion beams. The initial cavities of the future injector consist of two 750 MHz Radio Frequency Quadrupoles (RFQ), which are based on the compact CERN High-Frequency RFQ. These RFQs are designed to accelerate the ions from 15 KeV/u to 5 MeV/u. Each RFQ, with a length of 2 meters, comprises four...
It has been found in benchmark tests that some Single Spoke Resonator Type-2 (SSR2) cavities have early field emission onset as well as strong multipacting barriers. A longstanding hypothesis is that field-emitted electrons in the high electric field accelerating gap can migrate and ignite multipacting bands in the low electric field regions of the cavity periphery. In this study, we use...
A new longitudinal diagnostic has been proposed, the SPACEChip (Smith-Purcell ACcElerator Chip-based) diagnostic, which can infer information about the temporal profile of a particle bunch from the Smith-Purcell radiation spectrum generated when the bunch passes close to a dielectric grating. This is done using the bunch form factor after retrieving the phase. A simulated dielectric grating...
New materials beyond the standard bulk niobium have the potential to greatly improve the performance of Superconducting Radio Frequency (SRF) cavities. Specifically, thin coatings of normal conductors such as gold have the potential to improve the key RF performance metric of quality factor. We present progress on depositing thin gold layers onto 2.6 GHz SRF cavities and testing their RF performance.
Beam tomography is a method for reconstructing the higher-dimensional beam from its lower-dimensional projections. This provides an understanding of the beam's transverse phase space, enabling better modeling and predicting downstream beam loss. We will show methods of extrapolating confidence intervals of our reconstructed beam and explore a new beam tomography algorithms using Markov Chain...
In this opening plenary talk, the speaker will discuss advances in SRF technologies are enabling PIP-II, the new proton driver for the Fermilab Accelerator Complex currently under construction. This includes advanced cavity processing methods such as nitrogen doping and the mid-T bake and innovations in cryomodule design. He will present an overview of plans to evolve Complex in the PIP-II era...
Normal conducting radiofrequency (NCRF) technology plays a crucial role in the development of more compact and cost-effective linear accelerators with increased energy reach and intensity. Over the past few years, NCRF structures have seen remarkable progress in accelerating gradient, RF-to-beam efficiency and overall performance that could lead to compact linacs for a multitude of...
The performance of the SNS H- ion source has been improved over many years with a primary emphasis on extending its operational lifetime and enhancing its reliability. Recent research and development efforts have resulted in a significant boost in the output beam current, increasing from the existing capability of ~60 mA to more than 100 mA. This talk will discuss the advancements in design...
FLASH is undergoing major modifications in the framework of the FLASH2020+ project.
During the last upgrade phase in 2021/22 alterations to the superconducting linac have been the main priorty. Among other changes two accelerating modules were replaced by modern high gradient versions. This allows to operate FLASH routinely with electron beam energies exceeding 1.3 GeV and thus extends the...
In order to develop a stable LWFA based accelerator and demonstrate FEL generation, the unique LWFA platform was constructed in the RIKEN SPring-8 center and systematic experiments have being conducted financially supported by ImPACT (2013-2018) and JST MIRAI (2018-) programs. Although undulator radiation in an XUV spectral range driven by LWFA electron beams was successfully demonstrated on...
Plasma wakefield accelerators driven by particle beams are one promising method of advanced acceleration, with capable of providing accelerating gradient much larger than RF technology. One of the biggest remaining issues is coupling beams from one stage to another. This novel concept optimizes inter-plasma distances in a staged beam-driven plasma accelerator by drive-beam coupling in the...
Talk will cover state-of-the-art photocathodes for bright-beam and spin-polarized-beam generation.
A multileaf collimator comprising many individually controlled blades has been used to impose predefined transverse beam shapes to an electron beam. Afterwards transverse-to-longitudinal mapping transforms this shape into a longitudinal one. This technique opens a wide field of applications using individually tailored longitudinal beam profiles.
New materials beyond the standard bulk niobium have the potential to greatly improve the performance of Superconducting Radio Frequency (SRF) cavities. Specifically, thin coatings of normal conductors such as gold have the potential to improve the key RF performance metric of quality factor. We present progress on depositing thin gold layers onto 2.6 GHz SRF cavities and testing their RF performance.
The linear accelerator at the Facility for Rare Isotope Beams (FRIB) at Michigan State University uses a thin liquid Lithium film for charge stripping of high-intensity heavy ion beams. Energy straggling of the beam in the non-uniform Lithium film affects the energy distribution in the beam. This can lead to non-linear “tails” in the longitudinal phase-space beam distribution after bunching at...
The world’s first 1.3 GHz cryomodule containing eight 9-cell superconducting radio-frequency (RF) cavities treated by medium-temperature furnace baking (mid-T bake) was developed, assembled and tested at the Institute of High Energy Physics (IHEP), Chinese Academy of Sciences for the Dalian Advanced Light Source (DALS). The 9-cell cavities in the cryomodule achieved an unprecedented high...
Neutron scattering is an indispensable technique in material science research for providing solutions to important engineering challenges, including the ever-growing demand for more efficient batteries and fuel-cells. There are, however, limitations in the access and availability to the necessary neutron beams and this is worsening as nuclear research reactors continue to shut down. As a...
The Fermilab linac injection line consists of a 35 keV magnetron-type H- ion source, two-solenoid Low Energy Beam Transport (LEBT), 201 MHz 4-rod 750 keV Radio Frequency Quadrupole (RFQ), and a Medium Energy Transport (MEBT) containing 4 quadrupoles and a bunching cavity. The injector delivers 25 mA, 48 µs pulses to drift-tube linac at a repetition rate of 15Hz. The transmission efficiency has...
A Dielectric Disk Accelerator (DDA) is a metallic accelerating structure loaded with dielectric disks to increase coupling between cells, thus high group velocity, while still maintaining a high shunt impedance. This is crucial for achieving high efficiency high gradient acceleration in the short rf pulse acceleration regime. Research of these structures has produced traveling wave structures...
The Los Alamos Neutron Science Center (LANSCE) accelerator complex delivers both protons (p) and negative hydrogen ions (H-) and provides various beam patterns simultaneously to multiple users. The LANSCE linac front end is still based on Cockcroft-Walton voltage generators that bring proton and H- beams to 750 keV. An upgrade of the front end to a modern, RFQ-based version is now under...
The Cornell High Pulsed Power Sample Host Cavity (CHPPSHC) is a new system designed to measure the superheating field of candidate superconducting RF (SRF) materials, giving insight into their operational limits. This system is designed to reach peak magnetic fields of up to 0.5 T in only a few microseconds, allowing us to achieve a pure magnetic field quench on the sample. We present an...
The proposed novel 100 MeV injector for the LANSCE Accelerator Facility* is designed to replace the existing 750-keV Cockcroft-Walton-columns-based injector. The new Front End includes two independent low-energy transports for H+ and H- beams merging at the entrance of a single RFQ, with the subsequent acceleration of particles in the new Drift Tube Linac. The challenge of the design is...
Superconducting technology has significantly advanced the capabilities of particle accelerators, facilitating higher beam-power operations for fundamental research at a comparatively lower cost. However, the conventional implementation of superconducting technology introduces complexities in the form of cryogenic plants, cryogenic distribution systems and substantial construction and...
RadiaSoft is developing machine learning methods to improve the operation and control of industrial accelerators. Because industrial systems typically suffer from a lack of instrumentation and a noisier environment, advancements in control methods are critical for optimizing their performance. In particular, our recent work has focused on the development of pulse-to-pulse feedback algorithms...
Efforts aimed at developing klystron parameters have made significant progress in recent years. However, the ultimate parameter list of connected pulse compressors (PCs) has been given insufficient attention. We propose to develop a new high efficiency, high power gain pulse compressor based on the use of a dielectric storage resonator (100% dielectric filling factor) that is operated at a...
The Future Circular Collider electron-positron (FCC-ee) pre-injector complex demands high-performance RF accelerating structures to achieve reliable and efficient acceleration of beams up to 20 GeV. In this study, we describe an analytical approach to RF design for the traveling-wave (TW) structures including a pulse compression system to meet the rigorous specifications of the FCC-ee...
Neutron scattering is an indispensable technique in material science research for providing solutions to important engineering challenges, including the ever-growing demand for more efficient batteries and fuel-cells. There are, however, limitations in the access and availability to the necessary neutron beams and this is worsening as nuclear research reactors continue to shut down. As a...
Nb$_3$Sn is the most promising alternative material for the future of superconducting radio-frequency (SRF) technology, steadily advancing towards practical applications. Having a critical temperature twice that of niobium, Nb$_3$Sn offers the potential for developing smaller, more powerful, and more efficient accelerators. We have designed a comprehensive study to synthesize and characterize...
The ALBA injector consists of a 110 MeV Linac, a Linac-to-Booster Transfer Line and a full energy Booster that further accelerates the electrons up to 3 GeV. The Linac consists of two pre-bunchers, a buncher and two accelerating structures and it is powered by two pulsed 37 MW klystrons at 3 GHz. To overcome an eventual klystron failure the injector has been adapted to keep operative at lower...
The China Spallation Neutron Source (CSNS) has been operating at a stable beam power of 160 kW since March 2024, marking a significant 60% increase from its original design capacity. The ongoing CSNS upgrading project, known as CSNS-II. As part of this upgrade, a versatile Medium Energy Beam Transport (MEBT) system has been meticulously studied and redesigned to meet the stringent requirements...
Superconducting RF (SRF) structures are susceptible to frequency detuning from external vibrations and modal mechanical resonances in the structure. These small disturbances, known as microphonics, require additional RF power in CW accelerating structures since the frequency is constantly shifting. In the Jefferson Lab CEBAF accelerator, time and frequency data of this frequency shift have...
Simulation tools are critical to the prototype and validation of control algorithms prior-to and during commissioning of LLRF systems. Moreover for industrial systems, diagnostics that are available on test systems and in laboratory accelerators are not always available in the field. RadiaSoft has been developing an RF simulator suite that allows for rapid prototyping of control algorithms in...
In this paper, we derive the multipolar form of the change in transverse and longitudinal momenta of an ultra-relativistic charged particle that traverses a harmonic TM$_{mn0}$ mode in a pillbox cavity with a beam pipe. The relevant equations are first formalised before presenting results from the numerical integration of RF cavity field maps. In particular, we show that the radial dependence...
The installation and alignment of new beamlines and beamline components is necessary at any accelerator facility. The equipment and methods used to perform these precision driven tasks must be accurate, reliable and above all, easily repeatable. Using coordinate measuring machines (CMM), laser trackers, combined with Spatial Analyzer, Autodesk Inventor and other custom tools, it is possible...
RadiaSoft is developing machine learning methods to improve the operation and control of industrial accelerators. Because industrial systems typically suffer from a lack of instrumentation and a noisier environment, advancements in control methods are critical for optimizing their performance. In particular, our recent work has focused on the development of pulse-to-pulse feedback algorithms...
Sample alignment in neutron scattering experiments is critical to ensuring high quality data for the users. This process typically involves a skilled operator or beamline scientist. Machine learning has been demonstrated as an effective tool for a wide range of automation tasks. RadiaSoft in particular has been developing ML tools for a range of accelerator applications including beamline...
The Los Alamos Neutron Science Center (LANSCE) accelerator celebrated fifty years of operation in 2023. The LANSCE Modernization Project (LAMP) aims to ensure the future, by upgrading the aging hardware with a new replacement front end. This includes plans to replace the Cockcroft-Walton generators with a Radio-Frequency Quadrupole (RFQ), the low and medium energy transport (LEBT and MEBT...
High intensity linacs based on compact accelerating RF structures suffer from beam loading effects, which result into a bunch-to-bunch energy loss as a consequence of the beam-induced excitation of the fundamental accelerating mode. To track charged particles under this effect, the code RF-Track implemented a beam loading module in version 2.2.2. For ultrarelativistic scenarios in...
Beam loss in high-intensity H- linacs, such as the PIP-II linac at Fermilab, is a critical challenge that requires comprehensive study and understanding to ensure efficient and safe operation. This study explores the various beam loss mechanisms encountered in the PIP-II linac and its beam transfer line, drawing parallels from other high-intensity H- linacs. Key loss mechanisms include...
Superconducting technology has significantly advanced the capabilities of particle accelerators, facilitating higher beam-power operations for fundamental research at a comparatively lower cost. However, the conventional implementation of superconducting technology introduces complexities in the form of cryogenic plants, cryogenic distribution systems and substantial construction and...
This work describes a C-band RF system for the SAPS (Southern Advanced Photon Source of China) test bench linear accelerator.SAPS' RF testing system comprises of a photocathode electron gun and a 2-metre-long equal gradient acceleration device.The klystron power source delivers energy to the photocathode electron gun and the travelling wave acceleration structure,respectively.Test the...
As part of the PIP-II project at Fermilab, a pre-production cryomodule featuring 325 MHz Single Spoke Resonator type 2 (SSR2) superconducting RF cavities is under construction. These SSR2 cavities are fabricated by industry partners and undergo initial cold testing at our collaborating institution, IJCLab in France, utilizing low-power coupler. Subsequently, the cavities are subjected to final...
At the Los Alamos Neutron Science Center (LANSCE), an upgrade of the Proton Storage Ring (PSR) is potentially possible under the LANSCE Modernization Project (LAMP). For the PSR, reducing or at least controlling the beam losses could maximize the beam current delivered to the users and extend the run cycle via shortening the maintenance period. One of the approaches would be to install...
RadiaBeam and RadiaSoft have been developing a LLRF system for a 100MeV C-band LINAC. The system is based on a Keysight PXIE arbitrary waveform generator and ADCs. We are in the process of commissioning our system and validating its performance. In this presentation, we will provide details on amplitude and phase calibration, improvements to signal conditioning, comparisons between...
High-intensity Superconducting Radio Frequency (SRF) ion/proton linear accelerators (linacs) typically utilize Half Wave Resonators (HWR) and Single Spoke Resonators (SSR) for beam acceleration in the low-energy section of the linac. Because of lack of azimuthal symmetry, HWR and SSR geometries result in a quadrupole field component of operating mode accelerating field. This, in turn, results...
Abstract: Inductive Output Tube (IOT) is a vacuum electronic device used for generation of radio frequency power.. IOT based RF amplifiers are used in accelerator systems, industrial heating systems among other applications. It is compact in size and provides linear operation over its entire operating range with efficiency varying from60 to 70 percent. This paper proposes the conceptual...
IFMIF-DONES (International Fusion Materials Irradiation Facility - DEMO-Oriented NEutron Source) is a facility under construction as part of the European fusion roadmap. The facility, located in Granada (Spain), is a powerful neutron irradiation facility for validation and qualification of materials to be used in fusion reactors. The construction of the facility under the framework of the...
In accelerator physics, radio-frequency (rf) systems play a pivotal role in particle beam acceleration and diagnostics. This work presents a graphical interface designed with Python for interaction with rf instruments, enabling efficient data acquisition, processing, and visualization. Leveraging advanced software tools, the system enables efficient management and analysis of rf data. This...
A new type tuner is designed for the double spoke superconducting cavity of the Spallation neutron Source Phase II project in China. The tuner is mounted on the side of the cavity, and each module contains two tuner systems. In this paper, the structure and working principle of the tuner are designed and analyzed, also the testing results of the tuner with the superconducting cavity system as...
Laser wakefield accelerator (LWFA) and plasma wakefield acceleration (PWFA) have attracted a wealth of research interests since they can provide an accelerating gradient of ~100 GV/m. Recently, a series of LWFA/PWFA external injection experiments are foreseen to be carried out based on the linear accelerator (LINAC) of Beijing Electron-Positron Collider II (BEPCII). We hereby present a design...
Interest in helium ions for cancer therapy is growing, motivated by their superior conformability as compared to protons or carbon. Clinical trials are starting, using beams produced by large carbon synchrotrons. To exploit the potential of this new ion, a compact synchrotron is being designed to accelerate helium and protons at treatment energies, for about half the size of a carbon machine....
The Los Alamos Neutron Science center (LANSCE) facility at LANL is considering an upgrade of its front end, from the source to the end of a 100 MeV DTL. One of the main features of LANSCE is that it delivers several types of bunching systems to 5 users (Lujan Neutron Scattering Center, Proton Radiography Facility, Ultra Cold Neutron Center, Isotope Production Facility and the Weapons Neutron...
Wakefield structures are broadly employed in free electron laser (FEL) facilities for beam manipulation. Compared with cylindrical geometries, planar structures are typically preferred due to their increased flexibility, allowing for tunable wakefield strength through gap adjustment. However, these planar configurations can induce time-dependent quadrupole wakefields, which require careful...
This works presents the design of Beam Position Monitors for a 750 MHz linac for hadrontherapy studies.
BPMs will be installed in different sections of the Linac, operating at different energies, from the RFQ exit at 5 MeV/u to the end of the line after IH cavities at 10 MeV/u. The BPMs will allow measurement of the beam position, phase and time of flight (tof) studies. Therefore, being...
The China Spallation Neutron Source Upgrade Project (CSNS-Ⅱ) will use two debuncher cavities to supplement the beam energy at the end of the linear accelerator. The PI mode structure operating at room temperature is chosen, and each debuncher cavity is equipped with an online adjustable waveguide coupler. The main body of the coupler is the WR1500 waveguide, and a hole on the narrow wall of...
The power coupler is one of the most important components for superconducting cavities. Different from the normal conducting cavity, the superconducting cavity has to keep an ultra-high cleanliness environment for operation. As the vacuum barrier, power couplers are welded by many different materials and maybe the gas source since they are installed to the cavities after vertical test,...
As part of CERN's medical application research, a compact electrode system (< 30 cm) has been designed to facilitate low-current, multiparticle beam extraction and matching to a high-frequency RFQ. This study explores the innovative extraction system design and evaluates its simulation performance. Superfish (SF) and CST Studio Suite were employed to export the 2D and 3D electric field maps of...
LANSCE accelerator complex was successfully supporting nuclear science research at LANL for more then 50 years. However, the need of the upgrade of the linear accelerator becomes immanent due to development of the modern accelerator technology, and due to inevitable aging of the existing equipment. The first stage of the planned upgrade of the linear accelerator at LANSCE includes the...
The wakefield of a charged particle moving along an elliptical spiral-shaped trajectory in an infinite elliptical waveguide with resistive walls is calculated. A limiting transition to a flat trajectory located in one of the symmetry planes of the elliptic cylinder is carried out.
The Fermilab Side-Coupled Linac accelerates H- beam from 116 MeV to 400 MeV through seven 805 MHz modules. Twelve wire scanners are present in the Side Coupled Linac and four are present in the transfer line between the Linac and the Booster synchrotron ring. These wire scanners act as important diagnostic instruments to directly collect information on the beam’s transverse distribution. The...
Successful implementation of AI/ML models for online tuning of accelerators highlights the need for accurate simulation of beamline elements. Deployment of such models requires the inclusion of realistic element misalignments during the simulation process. This paper presents an original method to determine misalignments across entire beamlines and apply them to the previously developed TRACK...
The China Spallation Neutron Source (CSNS) project is now operating stably at the CSNS campus and the upgrade work (CSNS-Ⅱ) has already started in 2023, meanwhile, the preliminary research work on the south advance photon source (SAPS) project is in progress. More than six types of accelerator cavities: radio frequency quadrupole (RFQ), drift tube linac (DTL), double spoke superconducting...
Coherent synchrotron radiation has a significant impact on electron storage rings and bunch compressors, inducing energy spread and emittance growth in a bunch. Calculating the effects are computationally expensive, severally limiting the use of simulations. Here, we explore utilizing neural networks (NNs) to model the 3D wakefields of electrons in circular orbit in the steady state condition....
The patterns of occurrence of geometric resonances of the wakefield in a two-layer metal-dielectric cylindrical waveguide are determined. It is shown that the sequences of their resonant frequencies are determined by the thickness of the dielectric layer and the dielectric constant of the material filling it, and do not depend on the radius of the waveguide and on the serial number of the term...
The concept of a compact linear accelerator for industrial application suggested in reference* is based on the use of SRF cavities. The design of a thermionic electron source which can either be directly connected to a superconducting cavity or be part of a normal conducted injector cavity is described. The direct connection option is applied in a prototype 1½ cell 650 MHz SRF cavity capable...
With the development of radiotherapy,the need for high doses became strong.However, existing ion chambers are either more absorbent of X-rays in terms of material or are non-sealed, that subject to environmental influences and have a short lifecycle. Now we designed a new ion chamber, which have high dose pass-rate, sealed and long lifecycle under radiation environments. The dose pass-rate...
Fermilab recently completed production and testing of 1.3 GHz cryomodules for the LCLS-II project. Each cryomodule consists of eight TESLA-shaped superconducting elliptical cavities equipped with two High Order Mode (HOM) coupler ports. Measurement of the HOM spectrum is part of the incoming quality control of cavities at room temperature and the final qualification cold test of cryomodules at...
The implementation of High Pressure Rinse (HPR) not only ensures thorough cleaning of the inner high purity niobium surface of Superconducting Radio Frequency (SRF) cavities but also unlocks their full potential for achieving peak performance. By effectively removing contaminants and impurities, HPR sets the stage for enhanced superconducting properties, improved energy efficiency, and...
The Cornell High Pulsed Power Sample Host Cavity (CHPPSHC) is a new system designed to measure the superheating field of candidate superconducting RF (SRF) materials, giving insight into their operational limits. This system is designed to reach peak magnetic fields of up to 0.5 T in only a few microseconds, allowing us to achieve a pure magnetic field quench on the sample. We present an...
The world’s first 1.3 GHz cryomodule containing eight 9-cell superconducting radio-frequency (RF) cavities treated by medium-temperature furnace baking (mid-T bake) was developed, assembled and tested at the Institute of High Energy Physics (IHEP), Chinese Academy of Sciences for the Dalian Advanced Light Source (DALS). The 9-cell cavities in the cryomodule achieved an unprecedented high...
High-efficiency sub-GHz elliptical superconducting RF cavity are a critical enabling technology for multiple upcoming accelerator development projects such as for the Powerful Energy Recovery Linac for Experiments (PEARLE), the Future Circular Collider (FCC) FCC Booster, and for a certain realization of the FCC Collider ring. The ambitious quality factor and gradient requirements of these...
Space-borne accelerator technologies suffer from significant electron beam loss during beam acceleration and excessive energy spread of the output beam. LANL is proposing a deployable and compact solution using electrostatic potential depression (EPD) to achieve higher bunching, lower beam loss, and smaller energy spread. This buncher system involves the use of three EPD sections, each...
The European Spallation Source (ESS) is a state-of-the-art research facility currently under construction in Lund, Sweden. Upon project delivery, ESS will host the most powerful linear proton accelerator and a spallation target capable of producing the brightest neutron source in the world. In order to enable safe commissioning and operation of these potent systems, each system has a dedicated...
PIP-II cryomodules use a computer vision system (H-BCAMs system) to monitor the alignment of SRF cavities and focusing lenses during assembly, testing, and operation. This contribution details the integration of the H-BCAMs into the Spoke Test Cryostat (STC) at Fermilab, which is utilized for cold testing SRF cavities prior to their integration into the string assembly. Thermal and structural...
The 805 MHz RF power plant at Los Alamos Neutron Science Center (LANSCE) is powered by 44 86kV 1.25 MW klystrons which generate the required RF to produce 800MeV proton beam. These 805 MHz klystrons are of the modulated-anode type and are specially engineered for a long pulse duration of 1.475 ms pulse and 120 Hz repetition rate with a 15% duty factor. In this paper we will talk about the...
From being the first computer-controlled accelerator, through its 52-year long operational history, today the LANSCE Instrumentation and Control System (LICS) shows little resemblance of its early days. Over the past 5 decades, generations of control system engineers were faced with the challenge of maintaining the LICS. However, its maintainability depends on the ability that a failed...
Charged particle dynamics under the influence of electromagnetic fields is a challenging spatiotemporal problem. Current physics-based simulators for beam diagnostics are computationally expensive, limiting their utility for solving inverse problems in real time. The problem of estimating upstream six-dimensional phase space given downstream measurements of charged particles is an inverse...
The side-coupled cavity linac (CCL) at the Los Alamos Neutron Science Center (LANSCE) is tuned by matching a single-particle model to the RF phase signature of the modules. In the future, the High-Performance Simulator (HPSim), a GPU-powered, 6-D particle tracking code, will be used to reveal additional information that will assist with tuning. In this proceeding, the status of the HPSim-based...
The advent of c-band and x-band technology has made it possible to reduce the footprint of linear accelerators. Additionally, for industrial systems a more compact linac is enabling technology for burgeoning applications in security and defense. A key aspect to operating these machines in an industrial environments is stabilization of the amplitude and phase signals for the cavities. In this...
The proposed novel 100 MeV injector for the LANSCE Accelerator Facility* is designed to replace the existing 750-keV Cockcroft-Walton-columns-based injector. The new Front End includes two independent low-energy transports for H+ and H- beams merging at the entrance of a single RFQ, with the subsequent acceleration of particles in the new Drift Tube Linac. The challenge of the design is...
RadiaSoft and RadiaBeam are partnering on the development of a low level RF control system to support a 100MeV C-Band LINAC. Our system utilizes a Keysight data acquisition system and arbitrary waveform generator to drive the LINAC. The controllers are fully integrated with EPICS and are actively being commissioned. In this presentation we will provide an overview of the design architecture,...
At a heavy ion linac facility, such as ATLAS at Argonne National Laboratory, a new ion beam is tuned once or twice a week. The use of machine learning can be leveraged to streamline the tuning process, reducing the time needed to tune a given beam and allowing more beam time for the experimental program. After establishing automatic data collection and two-way communication with the control...
The linear accelerator at the Facility for Rare Isotope Beams (FRIB) at Michigan State University uses a thin liquid Lithium film for charge stripping of high-intensity heavy ion beams. Energy straggling of the beam in the non-uniform Lithium film affects the energy distribution in the beam. This can lead to non-linear “tails” in the longitudinal phase-space beam distribution after bunching at...
The Los Alamos Neutron Science Center (LANSCE) provides an 800-MeV H- ion beam to four of its five user facilities. Two new methods for studying the beam profile are being installed in the south transport lines to the Lujan Spallation Neutron Center and the Weapons Neutron Science (WNR) Facility. The Laser Profile Monitor (LPM) studies the longitudinal beam profile by neutralizing the H-...
Los Alamos Neutron Science Center uses a coupled-cavity linac (CCL) to accelerate H- beam from 100 to 800 MeV. This was the first CCL put into operation (1972) and is powered by forty-four 1.25 MW 805 MHz klystrons developed in the same era. A new initiative is underway to develop a replacement RF amplifier that fits in place of one klystron with HV modulator tank, and is functionally...
In 2019, the annual number of cancer cases exceeded 100 million, resulting in 10 million deaths worldwide. Radiation therapy stands out as one of the most effective methods for cancer treatment. Electron beams in the 100-MeV range can reach even deep-seated tumors without the need for surgical intervention. Thanks to novel high-gradient acceleration technologies, clinical facilities for...
At the Los Alamos Neutron Science Center (LANSCE), the accelerator operation is loss-dominated, and the losses are primarily minimized via operators’ intuition. The physics tune-up procedures for the linac, including the Drift Tube Linac (DTL) and the Side-Coupled Cavity Linac (CCL), does not take the bunch distribution into consideration. For the DTL, only statistical quantities like the full...
In electron linear accelerators, the improvement of the acceleration gradient of the acceleration structure has been a continuous research topic for scientists, which can reduce the construction cost of the entire accelerator by increasing the accelerating gradient. For the CEPC and HEPS projects at IHEP, S-band 3 meters long and C-band 1.8 meters long accelerating structure has been...
The Bhabha Atomic Research Centre (BARC) of Department of Atomic Energy (DAE) has indigenously designed, developed and tested high efficiency compact 7 kW and 20 kW solid state amplifier (SSA) systems at 325 MHz. These SSAs will be used for both Indian accelerators and Proton Improvement Plan II (PIP-II) project of Fermilab, USA. The PIP-II accelerator requires two levels of RF power at 325...
After shipment to the Daresbury Lab and return to Fermilab, the prototype HB650 cryomodule underwent another phase of 2K RF testing to ascertain any performance issues that may have arisen from the transport of the cryomodule. While measurements taken at room temperature after the conclusion of shipment indicated that there were no negative impacts on cavity alignment, beamline vacuum, or...
The Fermilab linac injection line consists of a 35 keV magnetron-type H- ion source, two-solenoid Low Energy Beam Transport (LEBT), 201 MHz 4-rod 750 keV Radio Frequency Quadrupole (RFQ), and a Medium Energy Transport (MEBT) containing 4 quadrupoles and a bunching cavity. The injector delivers 25 mA, 48 µs pulses to drift-tube linac at a repetition rate of 15Hz. The transmission efficiency has...
A Ytterbium-based photocathode gun drive laser is proposed for the Advanced Photon Source linac to replace the existing antiquated Nd:Glass laser. The proposed laser will readily operate at 30 Hz providing 0.3 mJ of 257-nm UV radiation per pulse yielding 1 nC from our copper cathode, s-band gun in support of user operations. In addition, the laser allows generation of lower-charge,...
Under the Broader Approach (BA) agreement the Accelerator Facility validation activities aim at demonstrating the acceleration of 125 mA D+ beam up to 9 MeV. This is the main goal of the Linear IFMIF Prototype Accelerator (LIPAc) under installation, commissioning and operation in Rokkasho.
LIPAc is currently operating in its Phase B+ configuration, which consists of all the beamline except...
The China Spallation Neutron Source (CSNS) is designed and constructed by physicists at the Institute of High Energy Physics (IHEP). It is the first pulsed neutron source facility in developing countries, which locates at Dalang Town of Dongguan city, the heart of the Guangdong-Hong Kong- Macao greater bay area. CSNS beam power reached design goal of 100 kW in 2020. The pre-research of CSNS...
FERMI is the seeded free electron laser (FEL) user facility at Elettra laboratory in Trieste, operating in the VUV - soft X-ray spectral range. In order to extend the FEL radiation to shorter wavelengths, an energy increase from 1.5 GeV to 2.0 GeV is required in the linear accelerator (linac). This result is achievable by replacing the present old sections with the newly designed accelerating...
The U4 single pass rf driver (SPRFD) concept as developed overwhelms heavy ion beam requirements for pellet ignition to meet the need to be investment grade, commercial IFE, to justify building the first-of-a-kind, HIF IFE regional energy and water supply facility, with co-located heavy energy-use industries, from a coordinated set of computer models supported by empirical data including...
This work is part of the development study of a linac injector for hadron therapy with carbon ion beams. The initial cavities of the future injector consist of two 750 MHz Radio Frequency Quadrupoles (RFQ), which are based on the compact CERN High-Frequency RFQ. These RFQs are designed to accelerate the ions from 15 KeV/u to 5 MeV/u. Each RFQ, with a length of more of 2 meters, comprises four...
A series of detailed Linac4 end-to-end simulations were conducted using RF-Track and benchmarked against PATH for validation. The simulations were performed from the RFQ entrance to the Linac4 end. In RF-Track, all the accelerating structures are described with calculated 3d field maps while the calculation time remains within minutes for half a million particles. Despite the inherent...
The CSNS consists of an H- linac as injector, the interaction of the residual gas with H- particles will strip the electrons to produce associated protons within the LEBT, which follow the H- into the subsequent accelerating structure. In order to avoid the adverse effects of proton loss on the device, the feasibility of employing a bump for associated proton separation at the MEBT was...
The Los Alamos Neutron Science Center (LANSCE) accelerator complex delivers both protons (p) and negative hydrogen ions (H-) and provides various beam patterns simultaneously to multiple users. The LANSCE linac front end is still based on Cockcroft-Walton voltage generators that bring proton and H- beams to 750 keV. An upgrade of the front end to a modern, RFQ-based version is now under...
The Linac for Diamond Light Source has been running with two 3 GHz klystrons, powering two 5.2m-long accelerating structures to deliver 100 MeV electron beam since the start of operation. By introducing a SLED pulse compressor system to generate a pulse capable to power both structures from one klystron, redundancy and reliability will be improved. With a 5 µs total pulse, it is possible to...
For assemblies of cavities in cleanrooms, single-use tooling systems are made for the alignment and installation of ancillary components such as couplers and bellows. To try and minimize the amount of tooling sets used, a design has been created to standardize alignment features to allow for assembly of different components with one set of tooling. A prototype set of tooling has been developed...
A Dielectric Disk Accelerator (DDA) is a metallic accelerating structure loaded with dielectric disks to increase coupling between cells, thus high group velocity, while still maintaining a high shunt impedance. This is crucial for achieving high efficiency high gradient acceleration in the short rf pulse acceleration regime. Research of these structures has produced traveling wave structures...
The ongoing multi-user upgrade of the superconducting ion linac, ATLAS at Argonne, will enable simultaneous acceleration and delivery of two different ion beams to different experimental areas. In the initial phase, one stable, nearly continuous wave, beam from the ECR ion source and one pulsed radioactive beam from the EBIS charge breeder of the Californium Rare Isotope Beam Upgrade...
This paper outlines the strategy aimed at mitigating the adverse effects of residual magnetic fields on the performance of pre-production SSR2 superconducting cavities within the context of the PIP-II project at Fermilab. Residual magnetic fields can significantly impact cavity performance, leading to reduced quality factor. To address this challenge, our strategy integrates various approaches...
In high-intensity linacs, bunch-to-bunch effects due to the excitation of short and long-range wakefields can lead to beam instabilities and beam breakup. Wakefields can be due to resistive or geometric effects excited in the RF structures or in the beam pipe. From version 2.3.0 onwards, the particle tracking code RF-Track has been modified to implement a multi-bunch beam model that simplifies...
The transverse emittance at the exit of the China Spallation Neutron Source（CSNS）DTL is measured regularly every year. However, recently, the measured transverse emittance growth became larger than the his-torical data. It is also bigger than the simulated emittance. The process of measurement, data analysis and matching methods used are almost the same. Several factors con-tributed to the...
As an initial part of a future linac for hadron therapy, two 750 MHz Radio Frequency Quadrupoles (RFQs) have been preliminarly designed by CERN, based on the compact HF-RFQ model. These RFQs aim to accelerate carbon ions from 15 KeV/u to 5 MeV/u. Each RFQ is composed of four individual modules.
Manufacturing imperfections and misalignments can result in local variations in the frequency and...
To minimize the contamination of SRF cavities, remote installation techniques are needed during the installation of components. Recent work at Fermilab has been performed to begin the process of developing techniques for assembling cavities using robotics. Multiple alignment methods were prototyped including alignment and computer vision methods. Using a remotely controlled robotic arm, the...
The PIP-II Project will receive fully assembled cryomodules from CEA and STFC-UKRI as in-kind contributions. Damage to these cryomodules during transport is understood to be a significant risk to the project, so an extensive testing and validation program has been executed to mitigate this risk. The centerpiece of this effort was the successful shipment, from FNAL to STFC-UKRI and back, of a...
The PIP-II linac will include thirty-five 325 MHz Single Spoke Resonators Type 2 (SSR2) cavities. Each cavity will be equipped with a tuner for resonance control. The tuner consists of mechanical frame with a motor for coarse frequency tuning and a piezoelectric actuator for fine frequency tuning. The tuner was tested for the first time at Fermilab on an SSR2 cavity. This dressed cavity-tuner...
The commissioning of the Normal Conducting Linac (NCL) of the European Spallation Source (ESS) in Lund (Sweden), started in September 2018 and was completed in July 2023.
The four NCL commissioning phases required the design, procurement, test, installation and operation of four distinct beam destinations in order to safely dump the proton beam and measure the current of protons with energy...
New materials beyond the standard bulk niobium have the potential to greatly improve the performance of Superconducting Radio Frequency (SRF) cavities. Specifically, thin coatings of normal conductors such as gold have the potential to improve the key RF performance metric of quality factor. We present progress on depositing thin gold layers onto 2.6 GHz SRF cavities and testing their RF performance.
A multi-harmonic buncher cavity, MHB, is being designed by ESS Bilbao for HIE-ISOLDE ISRS project at CERN, to bunch beam pulses with 5 keV/u input energy. The MHB will be tested with ESS Bilbao light-ion injector. Transverse beam dynamics simulations were carried out to analyse preliminary measurements from hydrogen beams produced at 5 and 10 kV. Results have demonstrated that ESS Bilbao...
Resonant cavities used in accelerating structures have been studied and used in excited modes other than the fundamental frequency TM accelerating mode. These cavities can also be overmoded to accomplish specific beam quality or bunch structures. A TE mode properly phased can be used to induce a transverse kick to an 800 MeV proton beam, such as the beam produced by the Los Alamos Neutron...
The ESS-Bilbao RFQ fabrication is completed. The RFQ will operate at 352.2 MHz and will accelerate a 45 mA proton beam from 45 keV up to 3.0 MeV. The RFQ is build up of 4 copper segments, for a total length of 3.2 m. Each segment is composed of 4 subparts, 2 major and 2 minor vanes, that are assembled together by using bolts, vacuum and RF gaskets, with no brazing used in the procedure. This...
The Los Alamos Neutron Science Center (LANSCE) accelerator is MW-class H-/H+ 800 MeV linear accelerator that serves five distinct user facilities that support Los Alamos National Laboratory (LANL) national security missions, commercial applications, and the Department of Energy’s Office of Science medical isotope production program. Now into it’s sixth decade of continuous operation, major...
Corrugated structures have recently been utilized for the time-resolved diagnostics of electron bunches and free-electron-laser (FEL) pulses across several FEL facilities: SwissFEL at PSI and European XFEL at DESY. This approach is simple and cost-effective, based on the self-streaking of electrons with a transverse wakefield enhanced in such structures.
In this work, we optimize the design...
The Proton Power Upgrade (PPU) Project at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory will upgrade or replace accelerator components for beam power capability from 1.4 to 2.8 MW and upgrade the first target station for 2-MW beam at 1.3 GeV and at 60 pulses per second. The remaining beam power will be available for the future second target station. PPU scope is...
The installation of the superconducting part of the ESS Linac is progressing towards the first operation at 870 MeV on the beam dump after summer 2024. A pilot installation of 1 Spoke and 1 elliptical cryomodules was conducted in the superconducting (SCL) part of the ESS tunnel in spring 2023, to practice the installation sequence as well as to complete the cryogenic distribution system (CDS)...
Since its inception, the field of Advanced Accelerators has regarded future particle-physics colliders as the ultimate application of > 1 GV/m accelerator technology [1]. Over the last decades, rapid experimental and theoretical progress [2,3,4] drove a conceptual evolution of potential future colliders based on Wakefield Accelerator (WFA) technology. The recent P5 Report [5] calls for...
The Facility for Rare Isotope Beams (FRIB), a major nuclear physics facility for research with fast, stopped, and reaccelerated rare isotope beams, was successfully commissioned and has been in operation for the past two years. Various ion beam species have been accelerated up to 300 MeV/u and delivered to the target. FRIB routinely provided 10 kW primary beams on target over the past year, a...
GANIL (Grand Accélérateur National d'Ions Lourds) started the operation of the SPIRAL2 superconducting linac in 2022. Experiments in the Neutron For Science (NFS) room, specific beam dynamics studies and different technical improvements are carried out during its operation in the second half of each year, after the run of the cyclotrons in the first half of the year. Up to now, accelerated...
The CSNS power upgrade project (CSNS-II) has been launched. It will increase the proton beam power from 100 kW to 500 kW, along with the new construction of 9 neutron instruments. CSNS-II will utilize superconducting accelerator structures to raise the linac energy from 80 MeV to 300 MeV. The pre-research on key technologies has been completed. The newly developed RF ion source is already...
In 2014, U.S. Congress recognized accelerator science and technology (AS&T) as a critically important cross-cutting topic within the U.S. Department of Energy (DOE) Office of Science (SC), leading to the creation of the Accelerator Stewardship program. Congress further clarified and broadened SC’s role in 2022 with the Chips and Science Act* to (1) advance accelerator science and technology...
The International Linear Collider (ILC), Compact Linear Collider (CLIC) and C3 are proposed designs for a next-generation high-energy electron-positron linear collider for exploring the Higgs-boson, top-quark and beyond-Standard Model sectors.
An overview and status of each collider project will be given, including the design, key technologies, accelerator systems, energy-staging strategies,...
Corrugated waveguide based colinear wakefield accelerator development at Argonne National Laboratory has been ongoing, achieving significant progress in fabrication and testing of most principal components of the accelerator module. A few 30 cm long corrugated waveguides with a 2 mm ID and short transition sections which provide fundamental mode power extraction and beam offset diagnostics via...
CiADS is the world’s first Accelerator Driven System under construction with a Mega-watt beam power. The linac of CiADS is designed to accelerate a 500 MeV and 5 mA proton beam with five-family superconducting resonators. The facility was lunched from mid 2021 and the hardware has finished the development of the prototype. In this presentation, we will present the physical design of the...
The studies commissioned by the U.S. Department of Energy have repeatedly identified electron sources as critical risk area for development of future accelerators including LINAC. To address this challenge, we initiated an effort of integrating 2D materials with cathodes in 2013. The aim was to protect environmentally susceptible but high performing alkali antimonide semiconductor...
FRIB is developing a new N-doping method with a simplified recipe. This recipe is called wet nitrogen doping, by adding nitric acid to the conventional EP acid. Nitrogen doping introduces impurities to the SRF surface, and reduces the BCS resistance by shortening the mean free path, which leads to a higher Qo. Conventional nitrogen doping, developed at FNAL and Jlab, requires a...
The project Anthem, funded within the Next Generation EU initiatives, foresees the realization of an innovative accelerator based BNCT (Boron Neutron Capture Therapy) facility at Caserta, Italy.
The INFN (LNL, Pavia, Napoli, Torino) has in charge the design and construction of the epithermal neutron source, that will assure a flux of 10^9 n/(s cm2) with characteristics suited for deep...
The superconducting heavy ion HELmholtz LInear ACcelerator (HELIAC) is designed to meet the needs of the Super Heavy Element (SHE) research and material science user programs at GSI in Darmstadt. The beam energy can be varied smoothly between 3.5 and 7.3 MeV/u, with an average current of up to 1 emA and a duty cycle of 100 %.
Recently, the first cryomodule CM1, was fully commissioned and...
In the field of accelerator physics, the quality of a particle beam is a multifaceted concept, encompassing characteristics like energy, current, profile, and pulse duration. Among these, the emittance and Twiss parameters—defining the size, shape, and orientation of the beam in phase space—serve as important indicators of beam quality. Prior studies have shown that carefully calibrated...
The superconducting (SC) driver linac for the Facility for Rare Isotope Beams (FRIB) includes 46 cryomodules for acceleration of heavy ions to 200 MeV per nucleon. FRIB cryomodules have been supporting sustainable and reliable delivery of high-power heavy ion beams, including 10 kW uranium beam, to the target for production of rare isotope beams to nuclear physics user experiments. The linac...
The KEK-ATF (Accelerator Test Facility) is an R&D facility for the final focus system to develop the nanometer beam technology required for the International Linear Collider. ATF is the best research environment for the study of wakefield effects on the nanometer small beam. The vertical beam size growth as a function of the bunch intensity was observed at the virtual interaction point (IP),...
The China Initiative Accelerator Driven System (CiADS), a multi-purpose facility driven by a 500 MeV superconducting RF linac, is currently under construction in Huizhou, Guangdong. In order to ensure the stable operation of the superconducting linac, we conducted optimization research on the beam quality in the front-end section of CiADS. By using the point scraping method, part of the beam...
CW magnetrons, initially developed for industrial RF heaters, were suggested to power RF cavities of superconducting accelerators due to their higher efficiency and lower cost than traditionally used klystrons, IOTs or solid-state amplifiers. RF amplifiers driven by a master oscillator serve as coherent RF sources. CW magnetrons are regenerative RF generators with a huge regenerative gain....
Conventional beam diagnostics only measure 2D projections of the phase space in x-x', y-y' and z-z'. To estimate a 6D beam phase space distribution for simulations, these 2D projections are multiplied without any correlations between them. It is true only if their degrees of freedom are independent. Recent studies show that there exists correlation across conjugate pairs. This correlation can...
Gun5, the new generation of high-gradient normal conducting 1.3 GHz RF guns for linac driven free-electron lasers like FLASH and European XFEL is under development at the Photo Injector Test facility at DESY in Zeuthen (PITZ). Its improved cell geometry and cooling concept allow for RF pulse durations of up to 1 ms at 10 Hz repetition rate, at gradients of ~60 MV/m at the cathode. Gun5 is also...
The studies commissioned by the U.S. Department of Energy have repeatedly identified electron sources as critical risk area for development of future accelerators including LINAC. To address this challenge, we initiated an effort of integrating 2D materials with cathodes in 2013. The aim was to protect environmentally susceptible but high performing alkali antimonide semiconductor...
Accurately assessing the difference between two beam distributions in high-dimensional phase space is crucial for interpreting experimental or simulation results. In this paper, we compare the common method of RMS moments and mismatch factors, and the method of statistical divergences that give the total contribution of differences at all points. We first show that, in the case of commonly...
The tumor therapy facility HIT, Heidelberg, Germany is in operation with light ion beams up to carbon since 2009. The 7 A MeV, 216.8 MHz synchrotron injector linac with a total length of 5 m is designed for the ion C^(4+) from an ECR ion source. The RFQ accelerates the beam from 8 A keV up to 400 A keV and is at present a bottleneck in beam transmission. After a careful analysis of the beam...
Additive Manufacturing (AM) has the potential to increase the performance of radio frequency (rf) cavity resonators while cutting manufacturing costs. To leverage this potential, AM processes and potentially post-processing techniques must be tailored to cavity requirements. Additionally, conventional manufacturing's quality assurance methods must adapt to the AM case requiring numerous...
Our recent experiments achieved EUV range undulator radiation amplification based on the stable electron beam obtained from laser wakefield accelerator (LWFA). The experiments were conducted on the LWFA platform in RIKEN Spring-8 center supported by ImPACT and JST MIRAI project. By optimizing the driving laser system and gas target, the reproducibility of the acceleration process has been...
In this paper, we investigate the usage of advanced algorithms adapted for optimizing the design and operation of different linear accelerators (LINACs), notably the superconducting linac ALPI at INFN-LNL and the ANTHEM BNCT facility to be constructed at Caserta, Italy. Utilizing various intelligent algorithms and machine learning techniques such as Bayesian optimization, genetic algorithms,...
RAON (Rare isotope Accelerator complex for ON-line experiments) is a heavy ion accelerator under construction in Daejeon, South Korea. RAON plans to operate a 28 GHz Electron Cyclotron Resonance Ion Source (ECRIS) with a fully superconducting magnet and is currently operating a 14.5 GHz ECR ion source with a fully permanent magnet. The 14.5 GHz ECRIS was manufactured by PANTECHNIK and...
The 60 kW CW AR RF HPA is critical major equipment in new RF system for ALS-U project at LBNL and so it has been designed & built with a modular redundant topology having large array of 96 RF final PA modules (each delivering ~ 700 W RF output) that are combined in parallel, and large 30 DC PS modules (each ~ 5 kW DC power) operating in parallel for achieving very high reliability (MTBF ~...
Recent studies indicate the magnitude of an anomalous decrease in the resonant frequency, so-called frequency dip, near critical temperature of superconducting niobium cavities, Tc, correlates to the cavity quality factor, Q0, and impurities introduced into the superconducting niobium surfaces, such as nitrogen or oxygen. We measured frequency dips in both 644 MHz fundamental mode (FM) and...
The project Anthem, funded within the Next Generation EU initiatives, foresees the realization of an innovative accelerator based BNCT (Boron Neutron Capture Therapy) facility at Caserta, Italy.
The INFN (LNL, Pavia, Napoli, Torino) has in charge the design and construction of the epithermal neutron source, that will assure a flux of 10^9 n/(s cm2) with characteristics suited for deep...
The superconducting heavy ion HELmholtz LInear ACcelerator (HELIAC) is designed to meet the needs of the Super Heavy Element (SHE) research and material science user programs at GSI in Darmstadt. The beam energy can be varied smoothly between 3.5 and 7.3 MeV/u, with an average current of up to 1 emA and a duty cycle of 100 %.
Recently, the first cryomodule CM1, was fully commissioned and...
A high-power superconducting linac with an energy of 30 MeV and a beam current of 100 mA has been proposed and designed. The primary challenge lies in beam loss control and a robust lattice structure to ensure stable operation. This paper discusses the physics design study, design principles, and simulation results considering machine errors. Extensive multiparticle simulations (a cumulative...
In the field of accelerator physics, the quality of a particle beam is a multifaceted concept, encompassing characteristics like energy, current, profile, and pulse duration. Among these, the emittance and Twiss parameters—defining the size, shape, and orientation of the beam in phase space—serve as important indicators of beam quality. Prior studies have shown that carefully calibrated...
The Japan Atomic Energy Agency (JAEA) is designing a 30-MW CW proton linear accelerator (linac) for nuclear waste transmutation. Space-charge is the primary challenge in achieving low losses and high beam quality for high-power accelerators, especially at low energy levels where space-charge forces are greater. To counteract the space-charge effects, the low-energy beam transport (LEBT) uses a...
RAON is a multi-purpose accelerator facility that can accelerate various heavy ion beams and rare isotope beams. The maximum energy of the uranium beam is 200 MeV/u. Sixty button beam position monitors were fabricated for use in SCL3, which accelerates the beam from 0.5 MeV/u to 18.5 MeV/u in a uranium case. BPM Electronics has developed position measurement using the IQ method for the 1st,...
CEBAF has been providing electron beams for nuclear physics experiments for almost 30 years. Ten years ago, it went through a major upgrade to increase the beam energy from 6 to 12 GeV. This paper summarizes the status of the CEBAF 12 GeV operations. We discuss the performance of the machine, limitations, and performance enhancements. Also, the paper discusses future upgrade plans.
Circular mode beams are beams with non-zero angular momentum and strong inter-plane plane coupling. This coupling can be achieved in linear accelerators (linacs) through magnetization of electrons or ions at the source. Depending on the magnetization strength, the intrinsic eigenmode emittance ratio can be large, which produces intrinsic flatness. This flatness can either be converted to real...
Muons, Inc is developing Compact Electron Linacs to meet the increasing demand for modern solutions to address diverse applications including Co60 replacement, isotope production, industrial uses, and sterilization of medical devices, food and water. The designs employ the Muons, Inc. – Richardson Electronics Limited 1497 MHz magnetrons that were designed, built, and being tested to replace...
Rotation of beams is usually quantified through its angular momentum rather than through its vorticity. However, the difference of the two transverse eigen-emittance is linked more strongly to vorticity as to angular momentum. It has been found that the dynamics of vorticity has remarkable similarity to the dynamics of the beam envelope along channels of solenoids and quadrupole triplets....
The superconducting (SC) driver linac for the Facility for Rare Isotope Beams (FRIB) includes 46 cryomodules for acceleration of heavy ions to 200 MeV per nucleon. FRIB cryomodules have been supporting sustainable and reliable delivery of high-power heavy ion beams, including 10 kW uranium beam, to the target for production of rare isotope beams to nuclear physics user experiments. The linac...
The Frankfurt Neutron Source FRANZ will be a compact accelerator driven neutron source utilizing the 7Li(p,n)7Be reaction with a 2 MeV proton beam. Follwoing successful beam commissioning of the 700 keV proton RFQ, further beam experiments including emittance measurements are currently ongoning. Preparations for conditioning and commissioning of the IH-DTL are running in parallel to the...
In recent years significant progress in increase intensity of H- beam in RF surface plasma sources. H- beam intensity in RF SPS of J-Parc was increased up to 145 mA.Intensity of H- in RF SPS of SNS was increased up to 110 mA, which is enough for European spallation source storage ring. Reduction of beamlet divergence in RF negative ion source for NBI is one of high-priority targets to be...
The research on heavy ion linac was began more than ten years ago initially to improve the HIRFL operation at IMP. In China, the first continuous wave (CW) heavy ion linac, SSC Linac, working at 53.667 MHz was developed as the SSC injector. The ion particle can be accelerated to 1.48 MeV/u with the designed A/q=5.17. At present stage, this CW linac has been put into operation and the Uranium...
In this paper, the design of a compact C-band SLED RF
Pulse Compressor for a Very High Electron Energy (VHEE)
FLASH machine is presented. A spherical cavity RF
pulse compressor - selected because of its compactness and
relative ease of fabrication - is adopted to compress the 5 𝜇s
RF pulse, down to 1 𝜇s obtaining a peak power gain greater
than 5. Both the RF and thermo-mechanical design...
This work presents the design and optimization of a compact electron linear accelerator capable of achieving an energy less than 5 MeV, specifically tailored for industrial applications. The innovative design incorporates a Superconducting RF photoinjector. A significant focus has been placed on optimizing the geometry of the SRF photoinjector cavity to accelerate high-charge and...
FLASH Therapy, a novel cancer treatment technique, aims to control the tumor-grown sparing the healthy tissue from radiation damage, increasing the therapeutic index. Translating FLASH therapy into clinical practice, especially for treating deep-seated tumors, necessitates achieving Very High Electron Energy (VHEE) levels within the 50-150 MeV range [2]. In the framework of the SAFEST project...
Electron accelerators utilized for radiation processing demand high beam currents and power outputs to maximize processing rate. Compared to conventional room-temperature accelerators, superconducting linear accelerators offer the capability to accelerate high-intensity continuous-wave (CW) electron beams. Therefore, the Design of a compact, 200mA, 2-5MeV CW superconducting linear accelerator...
A heavy-ion accelerator facility was constructed for the Rare Isotope Science Project (RISP) at the Institute for Rare Isotope Science (IRIS) in Daejeon, Korea. A cryomodule with quarter-wave resonators (QWRs) and half-wave resonators (HWRs) was installed in the SCL (Superconducting Linac) 3 tunnel,and the initial beam commissioning using argon beams has been completed. Additionally, a...
Construction of a heavy ion accelerator facility to support various scientific studies is underway. The heavy ion accelerator facility is largely comprised of SCL3 for low-energy acceleration and SCL2 for high-energy acceleration. SCL3 consists of 22 quarter wave resonators (QWR) with a superconducting acceleration cavity frequency of 81.25 MHz and 102 half wave resonators (HWR) with a...
Additive manufacturing (AM) has established itself as a powerful tool for rapid prototyping and the production of complex geometries. For use in a 433 MHz IH-DTL cavity, a CF-40 coupler is being developed that is manufactured from pure copper using a 3D printing process and has a water cooling concept that cannot be realized using conventional methods. The coupler consists of a ceramic window...
In a linear accelerator, phase drift in upstream cavities can adversely affect downstream cavity synchronization, leading to beam degradation and potential loss. J-PARC LINAC employs different phase reference signals for beam monitoring and RF systems, hindering direct comparison. Recent observations revealed susceptibility of reference signals to environmental effects in the Klystron Gallery....
EuPRAXIA stands for “European Plasma Research Accelerator with eXcellence In Applications". It's a next generation free-electron laser (FEL) aimed at developing a compact, cost-effective particle accelerator based on novel wake-field accelerator technology. Traditionally, high-energy physics requires higher acceleration voltages, so developing an X-band acceleration technology, enables the...
Superconducting Radio Frequency (SRF) photo-injectors offer the possibility of producing low-emittance electron beams in continuous wave operation. Among the various photo-emissive materials, bi-alkali antimonide is favored for its high quantum efficiency (QE) at visible light wavelengths. A development effort at FRIB is oriented toward the integration of advanced photocathodes into an SRF...
The KEK injector linac injects high-charge electron and positron beams into the high-energy-ring and low-energy-ring of SuperKEKB respectively.
The linac also injects electron beams to the two light source rings, PF ring and PF-AR. We operate simultaneous top-up injections into the four rings by using many pulsed magnets. We have been upgrading the linac to attain the higher-quality beam...
The mid-Infrared region (2-5 um) is currently a frontier of laser science with short durations, where many molecular absorbing spectrums exist. The oscillator free electron lasers have advantages against solid-state laser systems, that include the fundamental generations of high-intensity mid-IR pulses with femto-seconds scale short duration, continuous variations of the central wavelength,...
Nuclotron-based Ion Collider fAcility (NICA) is an accelerator complex under construction in JINR, in which superconducting linac-injector can accelerate protons up to 20 MeV and light ions to 7.5 MeV/u. To achieve this design target, a 325 MHz, beta = 0.21 niobium half-wave resonator (HWR) called HWR1 was developed jointly by IMP and JINR. This paper optimizes the electromagnetic design of...
FRIB is developing a new N-doping method with a simplified recipe. This recipe is called wet nitrogen doping, by adding nitric acid to the conventional EP acid. Nitrogen doping introduces impurities to the SRF surface, and reduces the BCS resistance by shortening the mean free path, which leads to a higher Qo. Conventional nitrogen doping, developed at FNAL and Jlab, requires a...
This paper describes the development status of solid-state switches for thyratron replacement. A 50 kV, 10 kA solid-state switch has been developed based on IGBT series stacking technologies, including voltage balancing and synchronous driving. The proposed stacking structure minimizes internal inductance and provides a fast current rising time of up to 7 kA/us. Additionally, the developed...
For high-intensity linear accelerators, space-charge halo mechanisms are largely classified into two families: particle resonances and parametric instabilities. The dominance between the fourth-order particle resonance and the envelope instability has been argued and studied. Our studies and previous literature indicate the dominance of particle resonances over parametric instabilities in...
An energy upgrade of the existing 100 MeV proton linear accelerator is considered at Korea Multi-purpose Accelerator Complex (KOMAC). 1 GeV proton linac for spallation neutron source is planned through 200 MeV linac upgrade as a near term project. Two options are considered for 200 MeV linac structure, one is a superconducting linac based on the half-wave resonator (HWR) and the other is a...
The Drift Tube Linac (DTL) for the European Spallation Source (ESS ERIC) will accelerate proton beam up to 62.5mA peak current from 3.62 to 90 MeV. The 5 cavities are now fully installed and tested in the linac tunnel. Moreover, in 2023 DTL1 to DTL4 have been RF conditioned to full power and beam commissioned with max peak current at short pulses. Relevant results of these activities are...
We are developing a laser-driven ion accelerator aimed at downsizing heavy ion therapy devices. The ion beam produced by this accelerator exhibits low emittance(transverse emittance is approximately 10-3 π mm-mrad and longitudinal emittance is approximately 10-5 eV・s), with a very short pulse width (about picoseconds). As a result, the peak current reaches the kA level. However, explosive beam...
The KEK-ATF (Accelerator Test Facility) is an R&D facility for the final focus system to develop the nanometer beam technology required for the International Linear Collider. ATF is the best research environment for the study of wakefield effects on the nanometer small beam. The vertical beam size growth as a function of the bunch intensity was observed at the virtual interaction point (IP),...
The International Fusion Materials Irradiation Facility – DEMO-Oriented Neutron Early Source (IFMIF-DONES) will provide a deuteron beam of unprecedented intensity for irradiation and characterization of materials to be used in fusion reactors. In recent years, the possibility to use a small fraction of this beam for other applications in parasitic mode was discussed. This not only has the...
In-situ plasma processing is a promising technique to reduce field emission in superconducting radio-frequency cavities and thus maintain maximum accelerator performance for long-term operation. Continuous-wave accelerators such as FRIB are more challenging than pulsed accelerators due to relatively weak coupling (Qext = 2E6 to 1E7 for FRIB) via the fundamental power coupler (FPC). This...
The China Initiative Accelerator Driven System (CiADS), a multi-purpose facility driven by a 500 MeV superconducting RF linac, is currently under construction in Huizhou, Guangdong. In order to ensure the stable operation of the superconducting linac, we conducted optimization research on the beam quality in the front-end section of CiADS. By using the point scraping method, part of the beam...
Producing bright electron beams is crucial for coherent light sources, where increasing the peak current is typically accomplished through bunch compression in magnetic chicanes. Alpha magnets, with their unique phase-space manipulation capabilities, have emerged as an attractive choice for compressing sub-10 MeV electron beams generated by radio frequency photoinjectors. This paper presents...
After dedicated machine upgrade measures at the GSI UNILAC, a high current beam campaign has been performed recently. The presented results were accomplished - among other things - with newly installed electrodes for the superlens (short RFQ-type matching section), working completely fault free.
Beam experiments have been conducted with high intensity proton beam (1.2 mA), carbon (1 mA 12C6+)...
The 50 years old GSI-UNILAC (Universal Linear Accelerator) as well as the heavy ion synchrotron SIS18 will serve as a high current heavy ion injector for the FAIR (Facility for Antiproton and Ion Research) synchrotron SIS100. The UNILAC together will provide for short and intense pulses. This contribution presents the results of the full performance high current uranium beam machine experiment...
High intensity linacs pose a challenge to efficient beam dynamics modeling due to the high numerical resolution required for accurate prediction of beam halo and losses. The code ImpactX represents the next generation of the particle-in-cell code IMPACT-Z, featuring s-based symplectic tracking with 3D space charge, parallelism with GPU acceleration, adaptive mesh-refinement, modernized...
Precisely calibrating RF superconducting radio-frequency linear accelerators is crucial for accurately assessing cavity bandwidth and detuning, which provides valuable insights into cavity performance, facilitates optimal accelerator operation, and enables effective fault detection and diagnosis. In practice, however, calibration of RF signals can present several challenges, with calibration...
INFN Milano - LASA recently concluded its in-kind contribution to European Spallation Source Eric, providing the 36 Superconducting Medium Beta cavities that will allow boosting the proton beam energy from 216 Mev to 571 Mev. The performances of the last four cavities, treated with Electro-Polishing as main removal step, are presented and compared with the results obtained on the remaining...
Nuclotron based Ion Collider fAcility (NICA) project is being realized in JINR, Dubna.The main goal of new collider facility is investigations of the heavy ions collisions with center-of-mass energy up to 11 GeV/u.Two injectors will provide the beams as for colliding and for extracted beam experiments.One of them is Heavy Ions Linear Accelerator (HILAC) intended to inject heavy ions produced...
Future High Duty Cycle (HDC) operation scenarios of the European X-ray Free Electron Laser (EuXFEL) promise increased bunch repetition rate and photon delivery, at the cost of changing system requirements and moving away from the current mode of Short Pulse (SP) operation. To assess whether the third harmonic cryomodule design is also suitable for Long Pulse (LP) and Continuous Wave (CW)...
Efficient control of frequency detuning for the radio-frequency quadrupole (RFQ) at the Facility for Rare Isotope Beams (FRIB) is still challenging. The transport delay and the complicated heat transfer process in the cooling water control system convolute the control problem. In this work, a long-short term memory (LSTM)-based Koopman model is proposed to deal with this time-delayed control...
A machine learning-based virtual diagnostic method for measuring the longitudinal phase space is proposed. Utilizing multiple measurements of bunch length from the Facility for Rare Isotope Beams (FRIB) accelerator, beam parameters are fitted with a concrete simulation model. A neural network model is trained to learn the correlations between the signals from beam position monitors (BPMs) and...
Obtaining the complete distribution of a beam in high-dimensional phase space is crucial for predicting and controlling beam evolution. Previous studies on tomographic phase space reconstruction often required linear beam optics in the relevant transport section. In this paper, we show that the method of maximum entropy tomography can be generalized to incorporate nonlinear transformations,...
A crucial milestone towards the final expansion stage of the HELIAC (Helmholtz linear accelerator at HIM & GSI) is the commissioning of the first fully equipped cryomodule, the so-called Advanced Demonstrator. The cryomodule comprises three accelerating superconducting crossbar H-mode cavities, a buncher and two superconducting solenoids. For modelling the beam dynamics of the Advanced...
The phenomenon of multipacting happens when in an RF cavity or wave guide electrons, randomly generated on the surfaces mainly by secondary emission and accelerated by the RF field, find e periodic and stable condition able to sustain the discharge. It is particularly detrimental for long pulse operation as in high intensity hadron linacs. An original view point for the associated dynamical...
Since the second half of 2013, Korea Multi-purpose Accelerator Complex (KOMAC) has been supporting user beam service by using a 100-MeV proton linac. As the operation period of the proton accelerator exceeds 10 years and the cumulative operating time surpasses 33,000 hours, we judge that it is an opportune time to establish a long-term plan to prepare for the aging of the accelerator. To...
CW magnetrons, initially developed for industrial RF heaters, were suggested to power RF cavities of superconducting accelerators due to their higher efficiency and lower cost than traditionally used klystrons, IOTs or solid-state amplifiers. RF amplifiers driven by a master oscillator serve as coherent RF sources. CW magnetrons are regenerative RF generators with a huge regenerative gain....
Modern CW or pulsed Superconducting RF (SRF) accelerators require efficient RF sources controllable in phase and power with a reduced cost. Therefore, utilization of the high-power CW magnetrons as RF sources in SRF accelerator projects was proposed in a number of works. But typically, the CW magnetrons are designed as RF sources for industrial heating, and the lifetime of the tubes is not the...
The SPIRAL2 superconducting LINAC accelerates beams of different species, in a large energy range. During operation, the beam requested by the physics can change quite often and it is mandatory that beams that have been already tuned can be obtained again by simple application of the machine parameters already used. This reduces the accelerator retuning time and increases the machine...
HZDR’s SRF Gun-II is an excellent demonstration of SRF technology application in the field of electron sources operating in continuous wave mode. As well known, quality of the photocathode is crucial for op-erational stability and reliability of an SRF gun. In this contribution, various studies on Cs2Te cathodes, in-cluding cleaning, preparation, transport/insertion, RF and beam operation will...
Physics applications have been developed and applied to the linac commissioning of the RAON injector and superconducting linac. Beam parameters obtained from the physics applications have been checked and validated during the beam commissioning using various ion beams.
Transverse Deflecting Structures (TDS) are commonly used in Free Electron Laser (FEL) facilities for the measurement of longitudinal information of electron beam, including bunch length, temporal distribution, slice emittance, etc. Shenzhen Superconducting Soft-X-ray Free Electron Laser (S3FEL) is a high-repetition-rate FEL recently proposed for scientific research and applications. In S3FEL,...
Conventional beam diagnostics generally measure 2D projections of the phase space in x-x', y-y' and z-z'. To estimate a 6D beam phase space distribution for simulations, these 2D projections are multiplied without any correlations between them. It is true only if their degrees of freedom are independent. Recent studies show that there exists correlation across conjugate pairs. This correlation...
A high beam brightness is a crucial requirement for an electron linear accelerator, with the electron source setting the lower limit for the achievable brightness. A superconducting radio-frequency photoelectron injector (SRF gun) stands out as an advanced electron source capable of delivering beams with superior properties compared to other continuous-wave injectors. Currently, SRF guns are...
The progress and status of the high intensity short pulse 325 MHz proton linac driver for the FAIR facility in Darmstadt is described. The proton linac is designed to deliver a beam current of 70 mA at an energy of 68 MeV. The design of the normal conductiong CCH cavities was carried out in collaboration with our partners at the IAP Frankfurt and industrial partners. First bead pull...
The Japan Atomic Energy Agency (JAEA) has been proposing an accelerator-driven nuclear transmutation system (ADS) as a future nuclear system. In preparation for the actual design of the CW proton linac for the JAEA-ADS, we are now prototyping a low-beta (around 0.2) single-spoke cavity. The cavity fabrication started in 2020. Most of the cavity parts were shaped in fiscal year 2020 by...
Sustainability and cost reduction are key factors for the development of future large particle accelerators. This motivated INFN LASA to initiate an INFN-funded R&D program dedicated to improve the performance of SRF Nb cavities in terms of quality factor (High-Q) and accelerating gradient (High-G). The R&D program will start by exploiting state-of-the-art surface treatments on 1.3 GHz...
The FLASH 2020+ project at DESY includes, among other modernizations, an upgrade of the electron beam energy. Two accelerator modules were replaced and the RF distribution of the other modules was optimized. The limiting factors such as cavity quenching and field emissions are identified and measured at acceleration modules. At a later stage, based on those measurements, a high-power...
Nb3Sn is one of the most promising materials for the next generation of superconducting RF (SRF) cavities. One reason is that Nb3Sn cavities can achieve high Q-values at 4 K, whereas conventional Nb cavities need to be cooled down to 2 K. This allows for the operation of SRF cavities with conduction cooling, eliminating the need for liquid helium, unlike conventional SRF cavities which require...
Achieving high-quality proton beams for accelerators hinges on effective beam tuning. However, the conventional "Monkey Jump" method, widely used for tuning, proves labor-intensive and inefficient. Through harnessing Reinforcement Learning (RL), a novel beam tuning strategy can swiftly emerge, making informed decisions based on the prevailing system status and control demands, offering a...
The performances and failure cases of the power couplers of the IFMIF/EVEDA RFQ and ESS DTLs have been analyzed with dedicated high-power test campaigns and multipacting simulation methods. The paper presents test and simulation methodology, results, and inputs for the next activities.
Field emission (FE) is a major contributor to degradation in the high-field performance of Superconducting Radio Frequency (SRF) cavities. The driver linac for the Facility for Rare Isotope Beams (FRIB) has been operating for user experiments since May 2022, using 104 quarter-wave resonators and 220 half-wave resonators in 46 cryomodules. We have used pulsed RF conditioning to mitigate the FE...
The RF reference phase in the SuperKEKB injector LINAC has been specially controlled for the stable beam injection to the main rings (HER/LER). The phase control system consists of three parts: MOFB, MOPS and SECT35PS. MOFB is the phase feedback system for drift compensation between the LINAC master oscillator (LMO) of 571.2 MHz and ring MO (RMO) of 508.9 MHz which has frequency ratio of 49/55...
Novel hadron radiotherapy accelerator-based systems require a fast-imaging capability, synchronized with the hadron beam, to allow positioning and treating the tumor practically at the same time. Such systems must operate at high repetition rates (~1,000 pulses per second) to provide reasonable treatment times. Currently, Argonne and RadiaBeam are collaborating on a high-gradient carbon...
The accurate measurement of longitudinal beam parameters is paramount for controlling beam losses in high-power superconducting linac accelerators, particularly for low-energy beams which are significantly affected by the compensative challenges of nonlinear effects and pronounced space charge effects. In this context, systematic simulation and experimental studies of longitudinal acceptance...
It has been found in benchmark tests that some Single Spoke Resonator Type-2 (SSR2) cavities have early field emission onset as well as strong multipacting barriers. A longstanding hypothesis is that field-emitted electrons in the high electric field accelerating gap can migrate and ignite multipacting bands in the low electric field regions of the cavity periphery. In this study, we use...
A new longitudinal diagnostic has been proposed, the SPACEChip (Smith-Purcell ACcElerator Chip-based) diagnostic, which can infer information about the temporal profile of a particle bunch from the Smith-Purcell radiation spectrum generated when the bunch passes close to a dielectric grating. This is done using the bunch form factor after retrieving the phase. A simulated dielectric grating...
The RAON facility, under the Institute for Basic Science (IBS) in Daejeon, is an advanced accelerator complex designed for research involving rare isotopes. RAON uses different types of cavities to accelerate various ions. The 81.25 MHz RF superconducting Radio Frequency Quadrupole (RFQ) cavity plays a key role in the initial acceleration of the ion beam. Supplying RF power efficiently to this...
The status of INFN LASA in-kind contribution to the PIP-II project at Fermilab is reported in this paper. The effort for the series production of the 38 INFN LASA designed, 5-cell cavities with beta 0.61 for the LB650 section of the linac commenced and the status of ongoing activities and major procurements is here conveyed. At the same time, preliminary tests on INFN LB650 cavity prototypes...
Gun5, the new generation of high-gradient normal conducting 1.3 GHz RF guns for linac driven free-electron lasers like FLASH and European XFEL is under development at the Photo Injector Test facility at DESY in Zeuthen (PITZ). Its improved cell geometry and cooling concept allow for RF pulse durations of up to 1 ms at 10 Hz repetition rate, at gradients of ~60 MV/m at the cathode. Gun5 is also...
A 325 MHz, optimal beta = 0.40 niobium half-wave resonator (HWR) called HWR040 for the superconducting driver linac of the China initiative Accelerator-Driven subcritical System (CiADS) has been designed and analysed at the Institute of Modern Physics, Chinese Academy of Sciences (IMP, CAS). The linac requires 60 HWR040s to accelerate protons from 45 MeV to 175 MeV. This paper mainly presents...
Significant progress towards the suitability of Additive Manufacturing (AM) metal parts for the production of linear accelerator components has been made in recent years. One significant factor for the suitability of AM parts to produce linac rf structures is the surface quality of the parts. Due to the inherently higher surface roughness of AM metal parts, post-processing is necessary to...
RadiaBeam has developed and built a Bunch Shape Monitor (BSM) prototype for measuring the longitudinal bunch distribution in hadron linear accelerators. The device has been designed to operate at 402.5 MHz and it incorporates three main innovations to improve its performance: a focusing field between the target wire and the entrance slit for better collection efficiency, a novel design of the...
The production of low energy high intensity heavy ion beams is challenging for the community. Several high intensity heavy ion beam accelerators for versatile purposes have been developed at IMP, such as LEAF, which is a low energy high intensity heavy ion accelerator complex for multidiscipline researches that features a superconducting ECR source, and a heavy ion beam linac. The major...
LINACs is a simulation framework for designing optics and beam dynamics of charged particles in particle accelerators. LINACs is an open-source software that enables the user complete control over all design and simulation parameters of RFQs. This includes beam-driven design, fully 3D simulation using precise quadrupolar symmetry, and rigorous Poisson solution for external and space charge...
Beam tomography is a method for reconstructing the higher-dimensional beam from its lower-dimensional projections. This provides an understanding of the beam's transverse phase space, enabling better modeling and predicting downstream beam loss. We will show methods of extrapolating confidence intervals of our reconstructed beam and explore a new beam tomography algorithms using Markov Chain...
The normal conducting part of ESS LINAC in Lund (Sweden) uses 5 DTL cavities, provided by INFN LNL as in-kind partner, to accelerate 60 mA proton beam from 3.9 MeV to 90 MeV. DTL1 have been tuned, installed in the accelerator tunnel and RF conditioned in 2021, DTL2, 3 and 4 in 2022, while DTL5 has been tuned and installed in summer 2023, but not yet conditoned. All the DTLs were equiped with...
The Alvarez-type post-stripper DTL at GSI accelerates intense ion beams with A/q <= 8.5 from 1.4 to 11.4 MeV/u. After more than 45 years of operation it suffers from aging and its design does not meet the requirements of the upcoming FAIR project. Prototyping of a new 108 MHz Alvarez-type DTL has been completed and series components for the 55 m DTL are under production and have been delivered...
Present status and future prospects of the iBNCT accelerator will be discussed. Several accelerator-based neutron sources for Boron Neutron Capture Therapy (BNCT) have been developed in the world. The iBNCT (Ibaraki, BNCT) is a linac-based BNCT facility which is operated by University of Tsukuba and KEK in close collaboration with the local government, Ibaraki prefecture. The accelerator is...
Linear accelerators for FELs have very high requirements for the accuracy of synchronization. The long and short term stability is influenced by various sources of interference. In this paper it will be shown which methods of stabilization exist and how synchronization accuracies up to the fs-level can be achieved.
Time-resolved diagnostics are fundamental for x-ray free-electron lasers (FELs). Radio-frequency (RF) transverse deflector structures (TDSs) are typically employed to characterize the temporal properties of the electron beams driving FELs. In this contribution, we present time-resolved measurements with a resolution below one femtosecond using a C-band and X-band RF TDS at SwissFEL....
Cleanroom processing and assembly are critical for ensuring optimal performance of SRF (Superconducting Radio Frequency) cavities. Human activities are a significant source of particle emissions in cleanrooms, posing a risk of cavity contamination. To mitigate this risk and reduce labor costs, the implementation of robotics in cleanroom environments has garnered increasing attention in recent...
Machine learning (ML) tools have been growing in popularity for accelerator applications, but still struggle with time varying systems, for which they require lengthy brute-force re-training. LANL has developed generative machine learning (ML)-based tools, that utilize adaptive model independent feedback control theory together with hard physics constraints, to make the tools much more robust...
The International Liner Collider requires a crabbing system to increase the luminosity of the colliding electron bunches. The ILC has a large crossing angle that requires compensation in order to meet the luminosity requirements. There are several frequency options proposed for the crabbing cavity design. Two crab cavity designs were selected to be prototyped in the pre-lab phase, following...
Distributed coupling linear accelerators (DCLs) represent a revolutionary approach to accelerator design, offering significant advantages over traditional standing-wave and traveling-wave linacs. DCLs achieve record-breaking efficiency and gradient while remaining highly reliable, even under extreme operating conditions. These advancements make them ideal for a wide range of applications,...
The “FLASH” effect is currently a topic of considerable interest in radio-oncology. We present the design of a novel VHEE linac, to be built and installed at CHUV (Lausanne), capable of producing electron beams which deliver radiation at dose rates and time scales consistent with the FLASH effect. The design is based on X-band radio-frequency technology, developed at CERN for the CLIC study....
The Compact X-ray Light Source (CXLS) is a compact source of femtosecond pulses of x-rays that is now commissioning in the hard x-ray energy range 6-20 keV. It collides the electron beam from recently developed X-band distributed-coupling, room-temperature, standing-wave linacs and photoinjectors operating at 1 kHz repetition rates and 9300 MHz RF frequency with a Yb:YAG 1030 nm laser beam...
Reliability is an important feature for high power particle accelerators. This is particularly true for Accelerator-Driven Systems (ADS), for that every beam interruption can strongly affect the availability of the nuclear reactor.
Many of these outages come from the loss of accelerating cavities or of their associated systems. Cavity failures can be compensated for by retuning other...
Many years ago, the use of a corrugated dechirper for energy-chirp control in a relativistic electron beam was experimentally demonstrated at the Pohang Accelerator Laboratory (PAL). Since then, a lot of efforts have been made at the PAL-XFEL to utilize the dechirper for the electron beam diagnostics and the short pulse generation as well as the removal of energy correlation. Currently, the...
For the time being, determining the cell-to-cell periodic solution for transporting intense beams has been limited to the spatial envelope. Recently, a numerical method for provision of full 4d-periodicity of all 10 beam moments of an intense 4d-coupled beam has been developed and benchmarked with tracking simulations. For instance, it will pave the path towards exploring the potential of beam...
Facility for Rare Isotope Beams (FRIB) requires diverse primary ion species beams to produce rare isotopes. The beam tuning time can be reduced by employing Machine Learning (ML) techniques. In this presentation, we aim to explore practical perspectives on shortening beam tuning time. Specifically, we discuss customization of Bayesian Optimization for maximum beam time utilization, and virtual...
Plasma processing is a common technique where the free oxygen produced in a low-pressure RF plasma breaks down and removes hydrocarbons from surfaces. This increases the work function and reduces the secondary emission coefficient of the treated surfaces. Jefferson Lab has an ongoing R&D program in plasma processing. The experimental program investigated processing using argon/oxygen and...
The FRIB diagnostics system covers an extensive range of primary and secondary beam intensities of 14 orders of magnitude and requires continuous improvements. The linac diagnostic system has provided straightforward linac commissioning and supports the development of many primary heavy ion beam species for producing rare isotopes. The diagnostics system for the secondary beam has a unique...
The linear accelerator RAON consists of an injector and a superconducting linac. The injector contains two ECR ion sources and an RFQ. These ion sources produce various ions from protons (A/Q=1) to uranium (A/Q=7.2), with an energy of 10 keV/u. The RFQ accelerates these ions to an energy of 500 keV/u. The superconducting accelerator consists of two types of superconducting cavities (QWR and...
Observation of ultrafast structural dynamics is very important for elucidating functions and creating new materials. We have been promoting research and development of ultrafast electron microscopes by generating relativistic femtosecond electron beam pulses using radio frequency (RF) accelerator technology. So far, we have fabricated the world's first ultrafast electron microscope using a...
We recently demonstrated generation of very high charge (1+ nC), very high energy (10 GeV) electron bunches from a nanoparticle-assisted laser wakefield accelerator [1]. While the experiment did yield record breaking results, the statistics were quite poor due to the very slow repetition rate of the Texas Petawatt Laser system. We are currently on a campaign to repeat and improve upon these...
We will present the results of the commissioning program to establish x-ray lasing and operation of the LCLS-II facility, based on the 4 GeV superconducting accelerator. The commissioning scope included the cryogenic systems, SRF and cryomodules, beam transport and two undulator beamlines serving the hard and soft x-ray programs. The talk will include a discussion of achieved beam performance,...
As an introduction, we will talk about the merit of the superconducting cavity and we about our applied research based on Compact ERL (cERL) in KEK, which uses the Nb superconducting cavity and can make energy recovery operation. The cERL’s characteristic using the high-current beam has a variety of applications; industrial applications using high-intensity terahertz light and mid-infrared FEL...
Several measures were developed and deployed at the pulsed linacs FLASH and European XFEL operated at DESY in order to reduce the energy consumption of the RF systems. A staged implementation of several techniques allowed energy savings up to 25% for both facilities, at the cost of reducing the RF overhead and increasing the complexity of the low-level radio frequency (LLRF) system. However,...
MeV ultrafast electron diffraction has become a new frontier for the study of molecular dynamics. With the temporal resolution of MeV-UED being limited by the electron bunch length at the target, electron sources used for this technique are becoming ever more intricate in the the push for shorter bunches length. However, moving to these complex setups makes them less feasible in a small-scale...
The development of a few MeV/n carbon ion injector using laser-driven ion acceleration by Target-Normal Sheath Acceleration (TNSA) is carrying out. And the prototype injector has been completed at QST-Kansai in Japan. The beam commissioning is underway and first data on beam characteristics obtained from them will be presented.
Additive manufacturing technologies, especially powder bed fusion, are rapidly taking their place in the technological arsenal of the accelerator community. A wide range of critical accelerator components are today being manufactured additively. However, there is still much of scepticism whether additive manufacturing can address the stringent requirements set to complete accelerator...
Two 1.5 GHz CEBAF C75-shape 5-cell accelerator cavities were coated with Nb3Sn film using the vapor diffusion technique at Fermilab and Jefferson Lab coating facilities. Both cavities were measured at 4 K and 2 K in the vertical dewar test in each lab, then assembled into a CEBAF quarter cryomodule at Jefferson Lab. The cryomodule was tested in 4 K and 2 K in the CryoModule Test Facility at...
The SNS beam test facility is a model of the SNS front end (source through medium-energy transport). On-going work at the BTF focuses on accurate modeling of the beam distribution to enable the prediction of halo losses (>100 parts per million). This presentation will discuss the latest progress towards this goal, including recent results after a reconfiguration of the test beamline. Good...
The Laboratory for Electron Beam Research and Application (LEBRA) at Nihon University has been developing free electron laser (FEL), parametric X-ray radiation (PXR), and terahertz (THz) wave sources in collaboration with KEK and the National Institute of Advanced Industrial Science and Technology (AIST) using a 100 MeV electron linac. Each of these light sources is used for both internal and...
SNRC and CEA collaborate to the upgrade of the SARAF accelerator to 5 mA CW 40 MeV deuteron and proton beams (Phase 2). CEA is in charge of the design, construction and commissioning of the linac downstream the existing RFQ (SARAF-LINAC Project).
The MEBT is now installed at SNRC and has been commissioned with both proton (cw) and deuteron (pulsed) beams. Transverse and longitudinal...
We have designed a tapered dielectric-lined waveguide for the acceleration of sub-relativistic electron bunches with THz-frequency electromagnetic pulses. We consider an example design based on a commercial 100keV electron gun and a THz generation scheme driven by a mJ-level regenerative amplifier laser system. With a 12μJ THz pulse we simulated acceleration of a 100keV electron bunch to...
Traveling-wave (TW) technology can push the accelerator field gradient of niobium SRF cavity to 70MV/m or higher beyond the limit of 50~60MV/m in Standing-wave (SW) technology. The early stages of TW SRF cavity developments had been funded by several SBIR grants to Euclid Techlabs and completed in collaboration with Fermilab through a 1-cell prototype and a proof-of-principle 3-cell TW cavity....
Recent developments in laser wakefield accelerators (LWFAs) lead us to consider employing this technology to accelerate electrons at the Advanced Photon Source (APS) facility. Previous experiments using LWFAs were performed at Argonne using the Terawatt Ultrafast High Field Facility. The injector complex serving the APS begins with an electron linac, producing beam energies on the order of 450...
The 19 MeV electron linear accelerator ELSA at CEA DAM has been in operation for 30 years. A renovation of the RF system was necessary to improve the reliability of the linac. The second part of the renovation deals with the 144 MHz RF amplifier, supplying power to the photo-injector.
The former tetrode based amplifier has been replaced by a 1.6 MW Solid State Power Amplifier delivered by...
A compact, high-voltage (HV) pulser in the nanosecond regime for transverse electromagnetic (TEM) kickers is presented. TEM kickers are electromagnetic deflectors used in particle accelerators to redirect bunches of particles out of their original trajectory into a new path, such as alternate beam paths, detectors, or other instrumentation devices. The circuit proposed in this design consists...
Recent developments in laser wakefield accelerators (LWFAs) lead us to consider employing this technology to accelerate electrons at the Advanced Photon Source (APS) facility. Previous experiments using LWFAs were performed at Argonne using the Terawatt Ultrafast High Field Facility. The injector complex serving the APS begins with an electron linac, producing beam energies on the order of 450...
Many accelerator physics problems such as beamline design, beam dynamics model calibration or interpreting experimental measurements rely on solving an optimization problem that use a simulation of beam dynamics. However, it is difficult to solve high dimensional optimization problems using current beam dynamics simulations because calculating gradients of simulated objectives with respect to...
MeV ultrafast electron diffraction has become a new frontier for the study of molecular dynamics. With the temporal resolution of MeV-UED being limited by the electron bunch length at the target, electron sources used for this technique are becoming ever more intricate in the the push for shorter bunches length. However, moving to these complex setups makes them less feasible in a small-scale...
A common challenge in online accelerator operations is aligning beams through a series of quadrupole magnets, especially when in situ beam position monitors are not present. Accelerator operators generally use a trial-and-error approach to solve this problem by sequentially measuring the centroid deflection of the beam as a function of quadrupole strengths. This is a challenging process that...
The Cool Copper Collider (C3) is an advanced accelerator concept for a e+ e- linear collider that utilizes a cryogenically-cooled copper accelerator technology. The C3 linac is envisioned to accelerate e+ and e- beams from 10 GeV to 125 GeV for a 250 GeV center of mass collisions. To reach the target luminosity, emittance has to be preserved through the whole main linac, taking into account...
Compact conductively cooled SRF industrial linacs can provide unique parameters of the electron beam for industrial applications. (up to 10MeV, 1MW). For ERDC project we designed normal conducting RF injector with thermal RF gridded gun integrated in first cell of multi-cell cavities. For design of the RF gun we used MICHELL software to simulate and optimize parameters of the beam. Output file...
BPMs have been used for decades since their easy-to-use absolute transverse position capability. Left signal minus right signal divided by the sum times the radius gives the beam position. The charge is “just” a relative measurement and has to be calibrated (or ironed) against a toroid signal. Even when the incoming charge variation is high (like 3% rms for the superconducting LCLS2), the...
A programmable signal processor-based credited safety control that calculates pulsed beam power based on beam kinetic energy and charge was designed as part of the Proton Power Upgrade (PPU) project at the Spallation Neutron Source (SNS). The system must reliably shut off the beam if the average power exceeds 2.145 MW averaging over 60 seconds. System calibration requires pedigree in...
Use of a cavity-based X-ray free electron laser (CBXFEL) is potentially a way to dramatically improve the stability and coherence of existing XFELs. A proof-of-principle project is underway as a collaboration between Argonne National Laboratory (ANL), The Institute of Physical and Chemical Research in Japan (RIKEN), and SLAC National Accelerator Laboratory. The CBXFEL is expected to operate...
The design and tuning of a storage ring for a fourth-generation synchrotron light source is very demanding. Recently, some research groups have considered techniques based on quasi-invariants of motion to address this task. This contribution presents tools, based on a quasi-invariant of motion method, for the description and optimisation of the electron dynamics in a storage ring. An overview...
The assembly of cavity string in the clean room is a tedious work that has noisy and painful steps such as cleaning the taped holes of a part. CEA together with the company INGELIANCE has developed a cobot: a collaborative robot operated by an technician one time and repeating the action without the operator. The cobot can work anytime without any operators: therefore it is working at night...
Accelerator-based light sources require high brightness electron bunches to improve performance in exploring structure of matter. Higher acceleration gradient is the key to generate high brightness electron bunches and is more feasible with higher frequency and shorter pulse length electromagnetic wave according to previous empirical formulas. A tapered rectangle waveguide structure driven by...
The Engineering Validation and Engineering Design Activities for the International Fusion Materials Irradiation Facility (IFMIF/EVEDA) are being pursued under the Broader Approach agreement between EURATOM and the Japanese government. The Linear IFMIF Prototype Accelerator (LIPAc) is under commissioning in Rokkasho, Japan to demonstrate the feasibility of the high duty (CW) and high current...
The Proton Power Upgrade (PPU) project at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL) has completed the installation and testing of all project scope required to meet threshold key performance parameters (KPPs), supported beam commissioning in June 2024, and transitioned to operations in July 2024. Increasing the beam energy from 1.0 to 1.3 GeV required the...
Compact SRF industrial linacs can provide unique parameters of the beam (>1 MW and >1-10 MeV) hardly achievable by normal conducting linacs within limited space. SRF technology was prohibitively expensive until the development of conduction cooling which opened the way for compact stand alone SRF systems suitable for industrial and research applications. Limited cooling capacity puts strict...
The performance of superconducting radiofrequency (SRF) cavities is critical to enabling the next generation of efficient high-energy particle accelerators. Recent developments have focused on altering the surface impurity profile through in-situ baking, furnace baking, and doping to introduce and diffuse beneficial impurities such as nitrogen, oxygen, and carbon. However, the precise role and...
The Virtual Pepper Pot (VPP) is a 4D transverse phase space measurement technique based on pepper-pot-like patterns that are generated by crossing each measured horizontal slit-based beamlet with all measured vertical slit-based beamlets. The VPP beam phase space distribution reconstruction and simulation are performed using the Beam Delivery Simulation (BDSIM) code, which is a Geant4 toolkit....
We have designed a compact RFQ to accelerate proton beam to 1 MeV. In this paper, we present the analyses and designs of the key parameters including frequency, vane voltage, aperture, modulation, etc. Simulations show the RFQ has good performance in transmission rate, power consumption and size.
We have designed a 4-solenoid LEBT, aiming at trans-porting high-current high-repetition short-pulse proton beam to RFQ acceptance. In this paper, we present the designs of the key parameters for the LEBT dynamics and the conical scraper. The influence of the solenoid magnetic fields and drift spaces were discussed. The performance of the scraper with different dimensions were compared. The...
RF superconducting cavities have been widely used in accelerators. The higher order modes caused by the wakefield radiation will lead to the beam instability, which is very harmful. So, it is necessary to depress the higher order modes. The photonic band gap (PBG) structure can effectively absorb higher order modes and suppress wakefield radiation. In addition, PBG cavities based on PBG...
The PAL-XFEL accelerator is operating simultaneous operation of HX (10 GeV) and SX (3 GeV). To facilitate simultaneous operation, kicker MPS is necessary, requiring both AC mode and DC operation mode. AC mode operates with a square waveform at a repetition rate of 60 Hz. It operates as a bipolar type with an output voltage of 200 V and an output current of 45 A. The MPS is implemented using...
The development of a few MeV/n carbon ion injector using laser-driven ion acceleration by Target-Normal Sheath Acceleration (TNSA) is carrying out. And the prototype injector has been completed at QST-Kansai in Japan. The beam commissioning is underway and first data on beam characteristics obtained from them will be presented.
A compact 10 MeV S-band irradiation electron linear accelerator has been developed to simulate electronic radiation in outer space and carry out electron irradiation effect tests on spacecraft materials and devices. According to the requirements of space environment simulation, the electron beam energy is adjustable in the range of 3.5 MeV to 10 MeV, and the average current is adjustable in...
Maintaining beam transport efficiency in the APS linac requires several feedback mechanisms to control orbit, phase, and other parameters. Presently, we apply pre-computed matrices to sets of deviations from fixed setpoints, corresponding to proportional linear feedback. This approach works most of the time but is slow and can become unstable at low charge levels. We explore two alternative...
Additive manufacturing technologies, especially powder bed fusion, are rapidly taking their place in the technological arsenal of the accelerator community. A wide range of critical accelerator components are today being manufactured additively. However, there is still much of scepticism whether additive manufacturing can address the stringent requirements set to complete accelerator...
Various types of radioisotopes (RIs) are used in the field of nuclear medicine for diagnosis, such as PET and SPECT. In recent years, RIs are applied to therapy of cancer and the Ac-225 has been confirmed to be effective in the treatment of advanced cancer. One of the promising RI production methods for medical application is the use of high-intensity beam in accelerators. In the case of an...
The SNS Drift Tube Linac (DTL) operates at 402.5 MHz and consists of 6 RF tanks, DTL1 to DTL6, which can accelerate the H- beam from 2.5 MeV to 87 MeV before entering the Coupled Cavity Linac (CCL). Each DTL tank assembly has 2 sets of horizontal and vertical electromagnetic steering magnets (24 in total) required for transverse beam steering. The coils of these steering magnets were routed...
Fundamental power couplers are utilized in SRF accelerators to transfer RF power from a source to the accelerating cavities. However, the issue of thermal heat load during high-power transmission in continuous wave (CW) mode operation poses a significant challenge for power couplers. To address this concern critical modifications have been implemented within the warm sections of the cERL...
Next-generation accelerator concepts, which hinge on the precise shaping of beam distributions, demand equally precise diagnostic methods capable of reconstructing beam distributions within 6-dimensional position-momentum spaces. However, the characterization of intricate features within 6-dimensional beam distributions using current diagnostic techniques necessitates a substantial number of...
The electropolishing process and cathodes have undergone modification and optimization for both low- and high-beta 650 MHz five-cell niobium cavities. Cavities treated with these novel electropolishing conditions exhibited superb surface quality and performance in baseline tests. Nonetheless, due to administrative constraints on project cavities, maximum gradient performance testing was not...
RF long-term stability (drift) is as important as RF short-term stability for the stable operation of particle accelerators including PAL-XFEL. Increasing the performance of LLRF itself becomes an important factor in maintaining the long and short-term stability of the RF field. The reference tracking method applied to LLRF is effectively used as a method of reducing the drift of the RF phase....
The operation of hard X-ray FEL in a self-seeded mode requires much more precise control of electron phase space distribution compared to a SASE mode. In PAL-XFEL, we developed a unique RF feedback control based on high precision e-beam characterization (combined with ~1 fs RF timing distribution) to maintain the optimized self-seeded FEL without drift during the user run.
This paper provides an overview of the current fabrication status of superconducting SSR1 spoke cavities intended for integration into the PIP-II SRF linac at Fermilab. It explores the ongoing development and fabrication processes of the jacketed SSR1 cavity, highlighting key modifications made in the mechanical design to enhance structural integrity.
Optics measurement is a common tuning and troubleshooting task which takes up a large amount of APS linac machine study time. It is of interest to explore more efficient methods to increase its’ speed and data quality. We previously tested Bayesian inference for determining linac magnet parameters, and in this work extend the method to directly measure linear optics and nonlinear deviations....
Two 1.5 GHz CEBAF C75-shape 5-cell accelerator cavities were coated with Nb3Sn film using the vapor diffusion technique at Fermilab and Jefferson Lab coating facilities. Both cavities were measured at 4 K and 2 K in the vertical dewar test in each lab, then assembled into a CEBAF quarter cryomodule at Jefferson Lab. The cryomodule was tested in 4 K and 2 K in the CryoModule Test Facility at...
The Proton Improvement Plan-II (PIP-II) accelerator upgrade at Fermilab marks a significant advancement in high-energy physics research. This initiative aims to enhance Fermilab's accelerator complex by replacing the existing linear accelerator with a warm front end (WFE) capable of accelerating H⁻ beams to 2.1 MeV. These beams are then further accelerated to 800 MeV using a superconducting...
Using 2D and 3D particle-core models, we thoroughly studied potential resonance interactions between particles and core in matched beams within complete periodic and double periodic channels. By keeping consistent geometrical structures and phase advances, we compared the Poincaré sections obtained from both models. The findings show that the differences between the models are negligible. This...
The RIKEN Linear Accelerator (RILAC), one of the injectors at RIBF was upgraded by installing a superconducting RILAC (SRILAC) to search for superheavy elements with element number 119 and above. Before the SRILAC upgrade, the machine protection system in the RILAC was constructed using simple relay circuits. On the other hand, most of the accelerators at RIBF other than RILAC have been...
After the discovery of Higgs boson at LHC, Chinese scientists have planned to build a “Great Collider”, that is a next-generation multinational particle accelerator research facility proposed as a circular electron positron collider (CEPC) and a super proton–proton collider (SPPC). The main component of the CEPC accelerator complex is the Collider ring, which has a circumference of 100...
The generalized longitudinal strong focusing (GLSF) scheme is a potential approach for a steady-state mi-crobunching (SSMB) storage ring, leveraging the ultra-low vertical emittance in the storage ring. It achieves active vertical-longitudinal coupling through an inser-tion unit, further compressing bunch length from the hundreds of nanometers scale in the main ring to the nanometers scale,...
In this work, we integrate and extend an HKL computation package into EPICS through a PyDevice** IOC. This provides EPICS users a generalized approach to mapping real motor rotation space to HKL reflections for a wide range of diffractometers (4-circle, 6-circle, kappa geometries). Utilizing PyDevice for EPICS IOC development allows us to bind core calculations written in C to Python,...
Recent studies have identified intra-beam scattering (IBS) as one of the processes that can have a significant impact on the beam dynamics of linacs with high-density and low-energy beams, such as in free electron sources (FELs), where IBS appears to be one of the effects that most limits their performance. Most existing simulation codes have been developed for circular lattices or assume...
For experiments requiring the longitudinal shaping of the beam at the exit of an electron linear accelerators, it is crucial to infer the initial beam profile at the entrance of the linear accelerator and key parameters. After passing through the dispersion section of beam bunch compressor, and the high-frequency system, the electron beam will undergo modulation on the longitudinal density....
Accurate beam emittance measurement and characterizing beam parameters are essential steps in the performance improvement and better physics studies of high-intensity proton beam accelerators. While various procedures exist for measuring beam parameters, they often come with limitations and provide only a linear space charge approximation of the phase space ellipse. To achieve better...
The objective of this research work is to design and develop laser-assisted thermal electron and hydrogen scattering, using theoretical model for elliptical and circular polarized laser. To develop the model, Volkov wave function for thermal case in elliptical and circular polarized laser field was designed and designed wave function is used to obtain S-matrix using Kroll-Watson approximation...
We designed, built and commissioned a beam diagnostic system based on a short S-band defector and a commercial klystron transmitter. A two feet long transverse-horizontally deflecting S-band rf structure (STCAV2) is installed the LCLS-II post-laser-heater diagnostic beamline at 100 MeV electron beam energy to measure the absolute electron bunch length and to allow time-resolved beam quality...
The utilization of large language models (LLMs) such as ChatGPT has seen a remarkable increase in various fields over the past few years. These models have demonstrated their versatility and capability in understanding and generating human-like text, making them invaluable tools in numerous applications. In this project, we explore the integration of a LLM into the Experimental Physics and...
The high-repetition-rate infrared terahertz free-electron laser (IR-THz FEL) facility are progressing in the preliminary research stage, which can achieve the demand for a tunable, high-power-light source in the long wavelength spectrum and form a complementary structure of advantages with the Hefei Advanced Light Facility (HALF). In this paper, we present the design of a bunch compressor...
Linear accelerators with dispersive elements experience projected emittance growth due to coherent synchrotron radiation (CSR) effects which become relevant for highly compressed beams. Even though this is a widely known effect, conventional measurement techniques are not precise enough to resolve the multi-dimensional effects in detail, namely the different rotations of transverse phase space...
Given the present availability of high-gradient accelerator technology for compact and cost-effective electron linacs in the 100-200 MeV energy range, the interest for Very High Energy Electron (VHEE) radiotherapy (RT) for cancer treatment recently reached an all-time high. Particular significance is assumed by the Ultra-High Dose Rate (UHDR) regime where the so-called FLASH biological effect...
The SRF community has shown that introducing certain impurities into high-purity niobium can improve quality factors and accelerating gradients. We question why some impurities improve RF performance while others hinder it. The purpose of this study is to characterize the impurities of niobium coupons with a low residual resistance ratio (RRR) and correlate these impurities with the RF...
Nb3Sn is the most advanced potential successor for niobium in superconducting RF accelerator cavities. Nb3Sn has a significantly higher critical temperature (18.3 K) compared to that of niobium (9.2 K). This has a large effect on the BCS surface resistance, and therefore, on the dynamic RF losses at 4.5 K. The higher critical temperature allows two important changes for cavity and cryomodule...
fragments will be thermalized in an existing gas catcher and formed into beams for stopped and reaccelerated experiments. A 6 MeV, 0.5 mA proton cyclotron will bombard a 7Li target to generate the needed neutrons. This configuration will replace the current source of radioactive ions, a thin plating of spontaneously fissioning 252Cf. nuCARIBU is expected to increase the overall intensity of...
Superconducting Radio Frequency (SRF) technology is a proven solution for generating high-power electron beams (EB), suitable for tasks like purifying wastewater from challenging impurities such as PFAS. This study elaborates on effectiveness of EB treatment and outlines design considerations for a 1.3 GHz SRF linac operating at 5 MeV with an average beam current of 10 mA. Nu-merical analyses...
The CERN Linear Accelerator for Research (CLEAR) at CERN is a user facility providing a 200 MeV electron beam for accelerator R&D and irradiation studies, including medical applications. In this paper we will outline the most recent improvements in CLEAR operation and beam control and delivery, and describe the upgrades under way, giving an update of their current status. These upgrades...
During the first cool down of the prototype HB650 cryomodule (pHB650 CM), high static heat loads have been measured compared to the estimation. Several analysis and calculations have been performed to explain this difference which led to cool down this cryomodule two additional times. Before each cool down, repairs and upgrades have been done, and instrumentations were added to identify the...
The Viton gate valves installed in the CEBAF beamline have significantly degraded after long-term operation in a radiation environment, generating numerous particles that cause heavy contamination and strong field emission. As a replacement, all-metal gate valves have been proposed for installation in the CEBAF beamline. In this paper, we present thorough comparison tests between the Viton...
The RIKEN superconducting heavy-ion linear accelerator (SRILAC) has been steadily supplying beams for super-heavy element synthesis experiments since its commission in January 2020 by addressing relevant issues. The over- all availability of the accelerator during beam supply periods, excluding regular maintenance and downtime due to major malfunctions, is approximately 90%, with the...
This paper describes the physical design of one linac injector for the proton/heavy ion synchrotron, which is under construction for Xi’an 200 MeV Proton Application Facility(XiPAF) heavy ion upgrading project. A heavy ion linac injector will be constructed close to the existing proton linac injector. The heavy ion injector consists of one electron cyclotron resonance(ECR) source, one low...
The PIP-II linac cryogenic distribution system (CDS) is characterized by extremally small heat inflows and robust mechanical design. It consists of a distribution valve box (DVB), intermediate transfer line, tunnel transfer line comprising 25 bayonet cans, and ends with a turnaround can. Multiple helium streams, each characterized by distinct helium parameters, flow through each of these...
We have studied high-power terahertz-wave sources using a normal-conducting S-band linac at the Laboratory for Electron Beam Research and Application (LEBRA) at Nihon University [1, 2]. The developed coherent transition radiation (CTR) had a high energy of 1 mJ per macropulse [3]. However, the peak power of the CTR was approximately 100 kW and did not reach 1 MW, i.e., the level at which...
Traveling-wave (TW) technology can push the accelerator field gradient of niobium SRF cavity to 70MV/m or higher beyond the limit of 50~60MV/m in Standing-wave (SW) technology. The early stages of TW SRF cavity developments had been funded by several SBIR grants to Euclid Techlabs and completed in collaboration with Fermilab through a 1-cell prototype and a proof-of-principle 3-cell TW cavity....
The SNS beam test facility is a model of the SNS front end (source through medium-energy transport). On-going work at the BTF focuses on accurate modeling of the beam distribution to enable the prediction of halo losses (>100 parts per million). This presentation will discuss the latest progress towards this goal, including recent results after a reconfiguration of the test beamline and...
The X-band Test Area (XTA) is a test accelerator beamline consisting of a 5.5 cell X-band electron gun followed by a 1-m long X-band linac. It delivers an 85 MeV electron beam up to hundreds of pC. Here we report the beam dynamics studies of XTA to prepare it for THz streaking and silicon carbide irradiation experiments. This paper talks about the requirement and the simulation studies to...
A new storage ring based on a multi-bend achromat (MBA) lattice has been built at the Advanced Photon Source. Currently, the commissioning process is underway to bring beamlines back into operation. The APS linac consists of two S-band thermoionic cathode guns at the front end and thirteen S-band traveling-wave RF structures, all powered by five klystrons. A major upgrade is in progress to...
We propose further investigations on the longitudinal-space-charge-impedance mechanism for inducing microbunching of relativistic electron beams within the Advanced Photon Source S-band linac. The microbunched content is evaluated by observing the coherent enhancements of optical transition radiation (COTR) generated as the beam transits a metal-vacuum interface. The facility also uniquely...
The bipolar pulsed electropolishing (BPEP), due to its HF-free feature, can offer much safer, more environmentally friendly, and lower-cost operation compared to the conventional electropolishing, using concentrated HF and H2SO4 as electrolyte. Jefferson Lab has developed the BPEP system using diluted H2SO4 only for implementing final surface processing of niobium SRF cavities, including...
The Laboratory for Electron Beam Research and Application (LEBRA) at Nihon University has been developing free electron laser (FEL), parametric X-ray radiation (PXR), and terahertz (THz) wave sources in collaboration with KEK and the National Institute of Advanced Industrial Science and Technology (AIST) using a 100 MeV electron linac. Each of these light sources is used for both internal and...
Conduction-cooled SRF niobium cavities are being developed for use in compact, continuous-wave electron linear accelerators for a variety of industrial applications. A 915 MHz two-cell cavity has been designed to achieve an energy gain of 3.5 MeV. The design of the cell shape aims at minimizing the peak surface magnetic field. Field flatness is achieved by adjusting the length of the outer end...
As one of the options for the injector of the Southern Advanced Photon Source, the C-band parallel feeding accelerating cavity has advantages such as the ability to operate under conditions of low pulse width (<1μs), high repetition rate, and high accelerating gradient. This paper will detail the electromagnetic design of the cavity, including the optimization of the electromagnetic parameters...
Free-electron lasers (FELs) send an accelerated electron beam through a magnetic undulator to provide a source of continuously tunable, short (10s of fs), high-peak power (GW-scale) radiation. FELs have found many applications, particularly in the infrared, extreme ultraviolet (EUV) and X-ray regimes. However, current EUV and X-ray FELs are large (100s of m) and expensive facilities, limiting...
This presentation details the design and fabrication process of a prototype of a normal-conducting X-band accelerator structure, which we denominate Smartcell. These structures, achieved through brazing/bonding techniques, are crucial components for future linear colliders.
We will cover the brazing/bonding geometry, materials selection and their implications, variations in heat cycles, and...
The Proton Improvement Plan II (PIP-II) project at Fermilab is the first U.S. accelerator project that will have significant in-kind contributions (IKC) from international partners. CEA joined the international collaboration in 2018 and will deliver 10 low-beta cryomodules as IKC to the PIP-II project, with cavities supplied by INFN-LASA (Italy) and DAE-VECC (India), and power couplers and...
One of the crucial control systems of any synchrotron is the Low-Level Radio Frequency (LLRF). The main purpose of an LLRF is to generate and maintain a stable electric field within the accelerator cavities by controlling its amplitude and phase.
SAFRAN Electronic & Defense Spain S.L.U. is currently developing the new digital LLRF to update the system in the ALBA Synchrotron Light facility...
The Proton Improvement Plan II (PIP-II) project at Fermilab is the first U.S. accelerator project that will have significant in-kind contributions (IKC) from international partners. As a part of the French IKC to this project, CEA will provide ten 650 MHz low-beta cryomodules (LB650) equipped with cavities from INFN-LASA (Italy), Fermilab (USA), and DAE-VECC (India), and power couplers and RF...
The X-ray free-electron laser facility SACLA generates X-ray SASE up to 20 keV in a compact 700 m long machine using a low-emittance thermal cathode electron gun, a high-field C-band normal-conducting 8 GeV linac and short-period in-vacuum undulators. The next upgrade plan for SACLA is to increase the repetition rate of the accelerator, which is currently 60 Hz, by one order of magnitude to 1...
Mechanical grinding is commonly employed to eliminate surface defects such as scratches and pits from niobium cavity surfaces or sheets before cavity fabrication. Subsequently, chemically buffered polishing or electropolishing is often utilized to completely remove residues of the polishing media and any defects induced by mechanical grinding, ensuring a pristine surface. In this study, we...
The CSNS-II superconducting Linac accelerator includes 20 sets of 324 MHz superconducting spoke cavities and 24 sets of 648 MHz superconducting Ellipsoidal cavities. The beam energy at the end of the superconducting Linac accelerator reaches 300 MeV. The 324 MHz solid-state power source supplies RF power to superconducting Spoke cavity, while the 648 MHz klystron power source supplies RF power...
The Radio Frequency Protection Interlock (RFPI) system watches over fifty signals near the superconducting cavities cryomodule. Its major role is to recognize faulty situations instantly and drop permits for the Low-Level Radio Frequency control system (LLRF) and Solid State Amplifier (SSA) operation.
The full-scale prototype RFPI is a recent version of the PIP-II dedicated system capable...
SNRC and CEA collaborate to the upgrade of the SARAF accelerator to 5 mA CW 40 MeV deuteron and proton beams (Phase 2). CEA is in charge of the design, construction and commissioning of the linac downstream the existing RFQ (SARAF-LINAC Project).
The MEBT is now installed at SNRC and has been commissioned with both proton (cw) and deuteron (pulsed) beams. Transverse and longitudinal...
The UK is conducting a multi-stage project to analyse the case for major investment into XFELs, through either developing its own facility or by investing at existing machines. The project’s 2020 Science Case identified a clear need for ‘next-generation’ XFEL capabilities including near-transform limited x-ray pulses across a wide range of photon energies and pulse durations; evenly spaced...
We have designed a tapered dielectric-lined waveguide for the acceleration of sub-relativistic electron bunches with THz-frequency electromagnetic pulses. We consider an example design based on a commercial 100keV electron gun and a THz generation scheme driven by a mJ-level regenerative amplifier laser system. With a 12μJ THz pulse we simulated acceleration of a 100keV electron bunch to...
Fermilab has optimized the surface processing conditions for PIP-II high beta 650 MHz cavities. This encompasses conditions for bulk electropolishing, heat treatment, nitrogen doping, post-doping final electropolishing, and post-processing surface rinsing. The technology has been effectively transitioned to industry. This paper highlights the efforts made to fine-tune the process and to...
The recent development of advanced black box optimization algorithms has promised order of magnitude improvements in optimization speed when solving accelerator physics problems. These algorithms have been implemented in the python package Xopt, which has been used to solve online and offline accelerator optimization problems at a wide number of facilities, including at SLAC, Argonne, BNL,...
The 65k pixel TimePix3 chip with ToA of 1.5625 [ns] nominal time resolution, allows timing and imaging studies using X-ray, neutron, and electron spectroscopies. The EPICS ADTimePix3 areaDetector** driver enables control and integration into the beamline acquisition system. This presentation will discuss the recent development of the beamline integration of the detector into neutron...
The delivery of high RF power---from hundreds of kW to MW---by klystrons, is linked with a high overall energy consumption. A research programme led by CERN in collaboration with the industry is being conducted to understand what limits klystron efficiency and how to develop high-efficiency klystrons. As a result of this program, two first prototypes of X-band (11.994 GHz) high-efficiency...
The timing system is a critical element in scientific facilities such as particle accelerator or laser ignition installations.
The different subsystems that integrate these scientific facilities need to have a common notion of time. This common time reference is provided by the timing system. Thank to that, it is possible to operate the machine in a time coherent manner and to properly track...
Additive manufacturing (AM) has become a powerful tool for rapid prototyping and manufacturing of complex geometries. A 433 MHz IH-DTL cavity has been constructed to act as a proof of concept for direct additive manufacturing of linac components. In this case, the internal drift tube structure has been produced from 1.4404 stainless steel, as well as pure copper using AM. We present the most...
In 2021, the Chinese ADS Front-end demo superconducting radio-frequency (SRF) linac, known as CAFe, successfully conducted a commissioning of a 10 mA, 200 kW continuous wave proton beam. During this commissioning, it was observed that the SRF cavity fault played a predominant role, contributing to approximately 70% of total beam trips. Upon the detection of fault signals, an acquisition...
Since its completion in 2017, Linac4, the new 160 MeV proton injector for the CERN accelerator complex, has undergone some tests to assess and improve reliability, until being connected to the Proton Synchrotron Booster (PSB) during the 2018-2020 Long Shutdown 2 (LS2). The performance requirements for the LHC high-luminosity upgrade have been successfully met, and during its first three...
HIAF is a heavy ion accelerator facility in China for nuclear physics research. The superconducting LINAC was used to accelerating beam energy up to 17MeV/u, then injecting to a Booster Ring. The linac are under construction since 2021, which includes 30 quarter-wave resonator (QWR) and 66 half-wave resonator (HWR). The first-batch production of cavity system have been completed. And the...
We report on the successful test for locating diamonds in ore by using an electron linac to create the 11C isotope atoms via the (gamma,n) reaction which has a large cross-section (8mb) at the Giant Dipole Resonance. The 11C atoms can be detected consequently using the Positron Emission Tomography (PET).
The technology is presently being scaled up for deployment in a mine with the goal of...
The SRF world has made considerable advances in the last 15 years on the performance of bulk niobium cavities. Processing recipes like N-doping and 120C baking are now being accepted as standard and consistently delivered by industry. New treatments like mid-T baking are now being incorporated into some project processing recipes as well. Thin film research is advancing with the mission to...
There is intense current interest in applying short-wavelength FELs to semiconductor manufacturing. Next-generation FEL techniques are being developed to address two advanced chip fabrication challenges: high-average-power lithography sources; and few-nm-resolution metrology. Aspects of the significant new activity in EUV lithography FELs, likely to impact the industry in the coming years, are...
