THPG
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Thursday Poster Session: THPG
23 May 2024, 16:00 -
18:00
THPG01
A Kick-and-Cancel injection scheme for Diamond-II
3240
The Diamond-II storage ring upgrade will provide users with 1-2 orders of magnitude brightness increase over the existing Diamond facility, for which a quasi-transparent top-up injection scheme will be a key performance requirement [1]. The ring was originally designed to use a single-bunch aperture sharing injection scheme [2], in which short stripline kickers are used to kick the injected bunch into the storage ring's dynamic aperture but remaining weak enough to avoid kicking the stored bunch outside the acceptance. A modification to this scheme which implements a kick-and-cancel method [3] shows promise for the stored bunch. The kicker power supplies are thus required to provide a double-pulse with few-microsecond pulse spacing. This new method is expected to significantly improve the transparency and reduce the recovery time for the targeted bunch, along with minimizing transverse wakefield effects and any interactions with the transverse multibunch feedback.
Paper: THPG01
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG01
About: Received: 09 May 2024 — Revised: 18 May 2024 — Accepted: 18 May 2024 — Issue date: 01 Jul 2024
THPG02
Performance optimization design of photocathode injector based on multi-objective genetic algorithm
3244
Generating beam with nC-level charge is of great significance for particle colliders. In order to achieve lower emittance and length of bunch, based on the photocathode injector, we designed a L-band gun and L-band accelerating tube. However, with many coupled parameters, it is difficult to optimize its performance to the limit when optimizing them separately. Therefore, we employed a multi-objective genetic algorithm for searching in the multi-dimensional parameter space and utilized a deep Gaussian process as a surrogate model to solve the high-dimensional parameter optimization problem. Through optimization, we successfully obtained the normalized transverse emittance of 3.4 π mm·mrad and the bunch length of 1.0 mm for a fixed charge of 5 nC. This indicates that our method can effectively improve the performance of the photocathode injector.
Paper: THPG02
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG02
About: Received: 15 May 2024 — Revised: 21 May 2024 — Accepted: 21 May 2024 — Issue date: 01 Jul 2024
THPG03
Temporal profile shaping for a dispersive section using a multi-objective genetic algorithm
3247
Our research focuses on the design of a beamline. Due to the numerous beamline components involved, without strict optimization of each component's parameters, the transmitted temporal profile of beam may distort, failing to meet the expected requirements. Additionally, different initial temporal profile of the beam will undergo longitudinal shaping during transmission through the beamline. Therefore, we aim to determine the combination of initial beam temporal profile at the cathode and the parameters of the beamline components based on the specific beam distribution at the exit. We propose the application of an improved multi-objective genetic algorithm to solve this problem. Through multiple optimization iterations for a given temporal profile, our algorithm consistently identifies multiple suitable combinations of initial beam temporal profile and beamline component parameters to produce the desired specific temporal profile of the beam.
Paper: THPG03
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG03
About: Received: 15 May 2024 — Revised: 23 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
THPG04
RF and multipactor analysis for the CARIE RF photoinjector with a photocathode insert
3251
At Los Alamos National Laboratory (LANL), we developed a 1.6-cell C-band RF photoinjector for the Cathodes And Radiofrequency Interactions in Extremes (CARIE) project. The injector will be used to study the behavior of advanced photocathode materials under very high RF gradients. The photocathodes will be prepared with an INFN-style photocathode plug, compatible with the plugs used by other institutions. This presentation will report the RF design of the photoinjector with distributed coupling and RF field symmetrization. Beam physics simulations show that symmetrized RF fields in the vicinity of the beam axis are essential for minimizing the normalized emittances for a 250-pC electron bunch. We will also present the design for the photocathode insertion and the analysis of the challenges related to reducing the peak electric fields, multipactor suppression, and resonant frequency tuning by fine adjustment of the plug position.
Paper: THPG04
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG04
About: Received: 14 May 2024 — Revised: 16 May 2024 — Accepted: 17 May 2024 — Issue date: 01 Jul 2024
THPG05
Evaluation of top-up injection by a single nonlinear kicker in Taiwan Photon Source
3254
The Nonlinear Injection Kicker (NIK) scheme for the Taiwan Photon Source (TPS) has been under study as a potential replacement for the current bump-based injection scheme. The evaluation encompasses three phases of the NIK scheme. In phases I and II, the orig-inal Booster to Storage Ring Transfer Line (BTS) is utilized to assess the performance of a prototype NIK. Phase III involves the redesigning of the BTS within the NIK injection scheme, thereby freeing up space occupied by the original four kickers used in the bump-based injection, for the insertion of devices. The positions of the NIKs, considerations, and limitations regarding the design of the new BTS, as well as other related issues, are thoroughly discussed.
Paper: THPG05
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG05
About: Received: 15 May 2024 — Revised: 22 May 2024 — Accepted: 22 May 2024 — Issue date: 01 Jul 2024
THPG06
Tune feedback system in the Taiwan photon source
3258
The paper outlines the successful implementation of a global tune feedback system at the Taiwan Photon Source (TPS) to compensate the tune variation resulting from adjustments in the gap and phase of the insertion devices. The global tune feedback system deployed in the TPS employs two families of quadrupole magnets to sustain betatron tunes at the desired working point. The adjustment currents (feedback quantities) are crucial for this process, which are calculated from a tune response matrix derived from the lattice model, with tune shift quantities provided by the bunch-by-bunch feedback system, and the algorithm of singular value decomposition (SVD).
Paper: THPG06
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG06
About: Received: 15 May 2024 — Revised: 20 May 2024 — Accepted: 20 May 2024 — Issue date: 01 Jul 2024
THPG07
TPS booster power supply performance experiment and monitoring program
3261
The TPS is a latest generation high-brightness synchro-tron light source scheduled to be commissioned in 2014. Its booster is designed to ramp electron beams from 150 MeV to 3 GeV at a frequency of 3 Hz. There are 54 dipole magnets, powered by one power supply unit, and 84 quadrupole magnets, powered by 4 power supply units according to their respective functions. During routine user time, a top-up injection occurs every 4 minutes. At this time, the stability of the booster's power supply units greatly affects the smoothness of the injection process. This paper will discuss how variations in the booster power output waveform affect injection and the monitor-ing program developed for this purpose.
Paper: THPG07
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG07
About: Received: 09 May 2024 — Revised: 21 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
THPG08
Development of a non-linear injection kicker for the TPS storage ring
3264
The TPS storage ring adopts a standard four kickers bump off-axis injection. This scheme is known to disturb stored beam during injections. The non-linear kicker injection concept provides a possible solution to facilitate top off injection with minimizing the oscillation of the stored beam. This non-linear kicker has zero Bx and By field in the center and an off-axis By displaced by 15 mm for TPS case. In this paper, we present the magnetic circuit design, consideration, fabrication, and first field measurement results of the TPS non-linear injection kicker.
Paper: THPG08
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG08
About: Received: 14 May 2024 — Revised: 18 May 2024 — Accepted: 18 May 2024 — Issue date: 01 Jul 2024
THPG10
Energy selection of synchrotron booster for SLRI beam test facility
3268
The SLRI Beam Test Facility (SLRI-BTF) is able to produce electron test beam with maximum energy of 1.2 GeV and various intensities from a few to millions of electrons per repetition. The main components of the SLRI-BTF are the Siam Photon Source (SPS) injector consisting of a 40-MeV linear accelerator, a low-energy transport beamline, a synchrotron booster increasing electron energy to 1.2 GeV, and a high-energy transport beamline. As the SLRI-BTF has successfully utilized the electron test beam to characterize pixel sensors for high-energy particle detectors and to perform high-energy electron irradiation, the test beam with lower energy ranges has also been requested by users. In this work, the test beam with lower energy can be obtained by changing the acceleration pattern of the SPS booster and adjusting high-energy transport beamline to match the extracted beam energy. Production of test beam with lower energy can be confirmed by test beam measurement at the SLRI-BTF experimental station.
Paper: THPG10
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG10
About: Received: 12 May 2024 — Revised: 19 May 2024 — Accepted: 21 May 2024 — Issue date: 01 Jul 2024
THPG11
Long range plasma experiment beam transport with UCLA MITHRA beam line
3271
This study focuses on developing beam-matching optics for the transport of the MITHRA beam into plasma to study long range plasma effects. To ensure successful injection into the plasma chamber, matching conditions are crucial at the entrance. A dedicated focusing system, comprising beam-matching optics, is designed to transport the beam from the 1.5-meter linear accelerator (linac) and align the necessary parameters at the plasma entrance. Optimization simulations employing Elegant and General Particle Tracer (GPT) codes, based on MITHRA gun data, have been conducted with promising results that align with our expectations. Further investigations involve simulating the PWFA interaction using advanced, fully relativistic, three-dimensional Particle-in-Cell (PIC) codes, namely OSIRIS and QuickPIC.
Paper: THPG11
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG11
About: Received: 16 May 2024 — Revised: 20 May 2024 — Accepted: 20 May 2024 — Issue date: 01 Jul 2024
THPG14
Automation upgrade of the CXLS photoinjector
3275
The automation upgrade of the photoinjector for the Compact X-Ray Light Source (CXLS) at Arizona State University is described. As the accelerator vault of the CXLS is only 10 meters long, the photoinjector drive laser is located in an enclosure inside the vault. Since ionizing radiation is present in this room during operations, it necessitates remote control of all devices used to optimize the laser spot. This includes multiple shutters, Galil motors, picomotors, a mirror flipper, LEDs, and remote lens controllers. To actuate these devices, a GUI was created with the use of MATLAB AppDesigner which communicates with the hardware through EPICS (Experimental Physics and Industrial Control System). Challenges with this GUI are described, along with the team’s efforts to finalize the control software. After these upgrades, the photoinjector laser characteristics can be adjusted remotely during operation and changes to the drive laser’s position, shape, and intensity can be made without interrupting beam time.
Paper: THPG14
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG14
About: Received: 15 May 2024 — Revised: 19 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
THPG15
Design and commissioning of a high-level control system for a medical isochronous cyclotron
3278
MEDICYC (MEDical CYClotron) is an isochronous cyclotron dedicated to radiotherapy which was built and commissioned in Nice, France, in 1990 by a local team aided by experts from CERN. The cyclotron accelerates H- to a maximum energy of 65 MeV and uses stripping to extract a proton beam. Its primary purpose is treating ocular melanoma by protontherapy but a significant research activity is also present on beam-lines dedicated for this purpose. An extensive refurbishment program of the cyclotron has been started to cope with the end-of-life and/or the obsolescence of several sub-systems. In this context, a new high-level cyclotron control system has been developed and implemented in 2021-2023. The primary responsibility of the system is the high-level coordination of the H- source, the RF system and the beam-line and cyclotron magnets to produce and deliver a beam with a given set of characteristics. A secondary responsibility is the collection, visualization and analysis of sub-system and beam data for monitoring and pre-emptive fault detection. In this contribution, the control system software architecture is presented and the infrastructure on which the systems are deployed is laid out.
Paper: THPG15
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG15
About: Received: 15 May 2024 — Revised: 19 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
THPG16
Investigation for the applicability of a Hall probe measurement in B-field control for synchrotron duty cycle optimization
3281
MedAustron is a state-of-the-art synchrotron-based accelerator complex that provides irradiation with proton and carbon ion beams. The implemented DCCT feedback based control of the current provides good results for magnets of the accelerator in terms of precision and accuracy. However, since the B-Field of the main ring dipoles is not directly controlled, parasitic, time consuming effects cannot be compensated. Hence, the implementation of a B-Field control system offers a major improvement opportunity for the operation. This contribution presents the measurement chain of the proposed solution which is centered around a Hall probe located in the so-called B-train magnet. This approach requires an assessment of the applicability of local Hall probe measurements for this purpose, including the development of a model for relating the respective local measurement to the integral field. Ultimately, the Hall probe has shown characteristics of high accuracy and a measurement uncertainty that is below the overall field error target of 2 units. The model was tested under laboratory conditions and an accurate estimation of the integral field has been observed in the scope of simulations.
Paper: THPG16
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG16
About: Received: 15 May 2024 — Revised: 20 May 2024 — Accepted: 20 May 2024 — Issue date: 01 Jul 2024
THPG17
Prototype control system for the Low Energy Branch ion beamline
3285
At the tandem ion accelerator laboratory of the Jožef Stefan Institute (JSI) in Ljubljana, Slovenia we are developing a control system for the Low Energy Branch (LEB) ion beamline. This activity is ongoing simultaneously with the hardware construction of the ion beamline branch dedicated to the research with low-energy ion beams with energies up to 30 keV. The LEB instrumentation is categorized into: a) Ion sources, b) Ion beam transport optics, and c) Accessories, including specialized detector systems and devices, used to prepare and maintain optimal experimental conditions. Therefore, key functionalities of the control system include the control of devices like vacuum pumps, power supplies, etc., data acquisition from sensors and detector systems, and ensuring reliable autonomous operation for high-precision physics experiments [1]. The control system will be implemented within the Experimental Physics and Industrial Control System (EPICS) environment [2], providing us with the tools required to develop a comprehensive and scalable control system. In this work, we present a block scheme, a device list, the prototype control system architecture of a minimal control system prototype currently operational in our laboratory.
Paper: THPG17
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG17
About: Received: 15 May 2024 — Revised: 19 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
THPG18
Cost-effective asset management for accelerator control systems: design and implementation for the ALS-U controls system
3289
This paper presents a cost-effective asset management system (AMS) designed to optimize the workflow of the accelerator control system for the Advanced Light Source Upgrade (ALS-U) project at LBNL. The AMS stores all essential information about equipment, including location, owner, hardware details, and firmware versions. Its user-friendly interface provides consistent access throughout the equipment lifecycle, from quality assurance to installation, through label printing, QR codes, and the Web application. By streamlining workflows and improving data consistency, the AMS contributes significantly to the efficiency and success of the ALS-U project.
Paper: THPG18
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG18
About: Received: 15 May 2024 — Revised: 18 May 2024 — Accepted: 21 May 2024 — Issue date: 01 Jul 2024
THPG19
ALS-U accelerator motion design and realization
3292
Transitioning from the aging ALS Geo MACRO motor controller, this paper details the meticulous selection process for a new, cost-effective standard to fulfill the diverse motion requirements of the upcoming ALS-U project. Targeting primarily simple stepper motors with varying current demands, the chosen solution seamlessly integrates into the existing ALS-U EPICS environment while preserving the established ALS motion architecture and EPICS IOC support. Notably, the solution maintains independence from Delta-Tau technology while comprehensively accommodating the project's required range of servo/stepper motor types and offering dedicated support for critical subsystems like Beam Scraper and Cold Finger motion. This document delves into the exhaustive selection process, from comprehensively summarizing the current architecture and ALS-U requirements to meticulously analyzing the results of a year-long evaluation of diverse vendor offerings.
Paper: THPG19
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG19
About: Received: 15 May 2024 — Revised: 19 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
THPG20
ALS-U AR RF equipment protection system
3295
This paper presents the design and status of Accumulator Ring (AR) RF Equipment Protection System (EPS) of Advanced Light Source Upgrade project at LBNL. The key components of AR RF EPS include a Master Interlock PLC subsystem handling supervisory control and slow interlocks in ms scale, an FPGA-based LLRF Controller managing fast interlocks in µs scale, a 60 kW high-power amplifier with standalone PLC-based slow (ms scale) and FPGA-based fast (µs scale) protection systems, and an RF Drive Control Chassis acting as primary RF mitigation device. The design of AR RF EPS is presented along with internal RF and external AR subsystems interfaces.
Paper: THPG20
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG20
About: Received: 13 May 2024 — Revised: 17 May 2024 — Accepted: 17 May 2024 — Issue date: 01 Jul 2024
THPG21
Accelerator control system software at LANSCE: vision and strategy for improvement and modernization
3298
The LANSCE accelerator is an 800 MeV linear accelerator delivering beams for more than fifty years. As it has aged, maintenance and upgrades to its control system software components have become challenging and often deferred due to operational and schedule constraints. As a result, we have a wide variety of new and old software, difficult to re-use, with a large staff burden. Data is stored in redundant sources, inconsistent formats, and outdated technology. Multiple tools exist for the same tasks. Some production software is updated without proper processes. We describe our approach to modernizing LANSCE control system software with proper development processes. We consider reduction of diversity, redundancies, data sources. Migration to modern technologies is also discussed. We explore the possibility of language standardization, and describe our database implementation and other future plans. Lifecycle management is also considered. This years-long effort will utilize a risk-based strategy to address the most urgent issues while also ensuring steady progress, ultimately resulting in a coherent and maintainable suite of control system software.
Paper: THPG21
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG21
About: Received: 14 May 2024 — Revised: 20 May 2024 — Accepted: 21 May 2024 — Issue date: 01 Jul 2024
THPG22
Implementation of EPU56 control system at the Taiwan Photon Source
3301
The elliptically polarized undulator with a period length of 56 mm, called EPU56, is part of the Taiwan Photon Source (TPS) phase-III beamline project. Its control system is built within the EPICS framework using motion controllers and EtherCAT. The control systems of EPU56 include a safety interlock system, which automatically stops movement based on limit switches, torque limit switches,emergency stop button, and readings from the enclosed linear optical encoder. In addition, the control system offers settings for adjusting the correction magnets' power supply and employs optical absolute encoder motors to control the movement of the Gap and Phase. In order to maintain stability during movement, PID control is applied to the motion process by the motion controller. To further enhance precision, the system also employs an integrator limit within the motion controller for additional adjustments. This paper describes the development of the control system and the enhancements made to the insertion device movement process.
Paper: THPG22
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG22
About: Received: 15 May 2024 — Revised: 20 May 2024 — Accepted: 20 May 2024 — Issue date: 01 Jul 2024
THPG23
Novel clock and trigger solutions with ultra-high precision delay to support time-resolved experiments at TPS
3305
The TPS (Taiwan Photon Source) is a third generation 3 GeV synchrotron light source. Some beamlines use synchrotron pulses in conjunction with laser pulses for pump-probe experiments, which is a time-resolved experiment method for capturing the temporal evolution of the pumped process. Periodic X-ray pulses are provided by the synchrotron light source as detecting light (Probe), and laser pulses can be used as a pump to excite a target, which changes a certain property when excited. Pump-probe experiments re-quire a synchronized laser system to alter the delay time between X-ray pulses and laser pulses. It has been built a laser synchronizer and timing support system. One direct digital synthesizer (DDS) with fine delay adjustment can change the laser pump pulse relative to the X-ray pulse. The clock fanout buffer with output dividers provides the synchronized clocks required by the laser oscillator and laser source. An SBC (single-board computer) is employed as a control interface The software architecture is created using the EPICS framework, which is compatible with the TPS control system, and a GUI with the ability to adjust the time delay is created. The efforts will be described in this report.
Paper: THPG23
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG23
About: Received: 14 May 2024 — Revised: 16 May 2024 — Accepted: 16 May 2024 — Issue date: 01 Jul 2024
THPG24
Real-time data acquisition with CompactPCI serial platform at PSI
3308
Data acquisition (DAQ) is an ubiquitous feature in modern particle accelerator measurement and control systems. At the Paul Scherrer Institut (PSI), a next generation of electronic devices is being designed to meet the demands of upcoming renewal of facilities. The new developments utilize the CompactPCI Serial (CPCI-S.0) platform, and will cover a diverse set of applications, including Low Level Radio Frequency (LLRF), Longitudinal Beam Loss Monitoring (LBLM), and Filling Pattern Monitoring (FPM) systems. Careful design considerations and selection of an optimal architecture are crucial to fulfill a variety of DAQ requirements such as maximum frequency of acquisition, size of the data and different modes of triggering. In this contribution, we focus on the real-time DAQ implementations utilizing a multiprocessor system on chip (MPSoC) technology. We review the IP components developed in-house at PSI that provide the DAQ functionality. We demonstrate, that by reusing the IP components development, prototyping and testing of applications requiring the DAQ are accelerated.
Paper: THPG24
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG24
About: Received: 14 May 2024 — Revised: 18 May 2024 — Accepted: 18 May 2024 — Issue date: 01 Jul 2024
THPG28
Status of the transverse bunch-by-bunch feedback system at APS-U storage ring
3311
Transverse bunch-by-bunch (BxB) feedback system has been designed, fabricated, installed, and tested with beam at the Advanced Photon Source Upgrade (APS-U) storage ring. The transverse feedback system (TFB) is designed to suppress coupled bunch instabilities and single bunch instabilities. It adapted a stripline kicker design which has the same profile as the APS-U injection/extraction kickers. The system uses digital controllers which provide powerful diagnostics, in addition to its major functionality for feedback control. This paper presents the status of the TFB system including early beam commissioning results.
Paper: THPG28
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG28
About: Received: 15 May 2024 — Revised: 20 May 2024 — Accepted: 20 May 2024 — Issue date: 01 Jul 2024
THPG29
A multi-variable approach to mid-ranging control for unified operation of fast and slow correctors in fast orbit feedback system
3314
Advanced Photon Source Upgrade (APS-U) Fast Orbit Feedback (FOFB) system uses 160 fast and 160 slow corrector magnets to stabilize orbit measured at 560 Beam Position Monitors (BPM). We plan to operate both fast and slow correctors in a unified feedback algorithm at 22 kHz correction rate. Mid-ranging control is a proven approach for feedback systems with two manipulated inputs each exerting distinct dynamic effects to regulate a single output. This method resets the fast input to its chosen DC setpoint and proves beneficial when cost of fast input is more than the slower one. Unified operation of fast and slow correctors is a fitting application to mid-ranging concept which is well founded for two input one output systems. In this work, based on the cross-directional nature of the FOFB system we developed a multi-variable approach to mid-ranging control. It can be applied to FOFB with multiple fast and slow correctors, and multiple BPMs. Performance of proposed scheme is tested in simulations with APS-U FOFB prototype model in MATLAB. The feedback loop with fast and slow correctors is stable with mid-ranging algorithm, and the fast corrector drives effectively tracked setpoints.
Paper: THPG29
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG29
About: Received: 16 May 2024 — Revised: 21 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
THPG30
Improvement of the LHC orbit feedback testing framework
3318
During the Long Shutdown 2 (LS2 2019-2021) of the LHC, the orbit feedback correction software (OFB) of the LHC was redesigned to satisfy new requirements for LHC Run 3 (2022-2025) and to clean up legacy functionalities. The OFB is an essential component of LHC high intensity operation since the orbit must be stabilized to a fraction of the beam size during the entire LHC machine cycle. Redesigning such an essential and complex system during shutdowns requires thorough testing of the system functionality. The existing OFB testing system has been reviewed and improved based on the experience of LHC Run 2. An automatic, continuous integration tool has been put in place to validate future software developments before putting them in production. The solution for the OFB testing will be presented in this contribution.
Paper: THPG30
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG30
About: Received: 12 May 2024 — Revised: 20 May 2024 — Accepted: 21 May 2024 — Issue date: 01 Jul 2024
THPG31
First studies on error mitigation by interaction point fast feedback systems for FCC-ee
3322
During operation, the Future Circular electron-positron Collider (FCC-ee) will be subject to vibrations from mechanical sources and ground motion, resulting in errors with respect to the closed orbit. To achieve physics performance, luminosity and beam lifetime must be kept to design specifications. To correct for errors at the IPs, a fast feedback system is required. In this paper, we present the tolerances for the allowable beam offsets at the interaction points (IPs) and propose a fast feedback system to address these errors, with the methods of detecting and correcting errors discussed.
Paper: THPG31
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG31
About: Received: 14 May 2024 — Revised: 21 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
THPG32
BPM feedback for LLRF energy and phase regulation in charge stripping beamlines
3326
Charge stripping is inherent for high power ion accelerators such as the FRIB LINAC. However, at high power, strippers require motion to prolong the operational life of the stripping media, or by flowing a liquid Lithium film. The charge stripping process introduces energy losses that vary with the actual Lithium film thickness, which can result in observable beam losses along the tuned beamline at high on-target beam power, above ~100 kW, if not adequately mitigated. BPM phase feedback is used in real-time to compensate for these effects, controlling upstream RF cavities in order to maintain a constant beam energy and phase post-stripper, which significantly reduces beam energy fluctuations.
Paper: THPG32
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG32
About: Received: 15 May 2024 — Revised: 18 May 2024 — Accepted: 18 May 2024 — Issue date: 01 Jul 2024
THPG33
Experimental results on longitudinal RF beam phase feedback in the heavy-ion synchrotron SIS18
3329
In the SIS18 heavy-ion synchrotron at GSI, RF beam phase feedback systems are developed and tested with beam for the damping of coherent longitudinal bunch oscillations. In particular, a beam phase control system is currently commissioned for the damping of longitudinal dipole oscillations. The feedback system has to cope with both, a large RF frequency span (400 kHz to 5.4 MHz) and synchrotron frequencies of up to 6 kHz. It has to be compatible with several beam manipulation schemes such as dual-harmonic, bunch merging, and bunch compression. The system relies on recent upgrades of the SIS18 LLRF topology including a newly developed multi-purpose DSP system that is used for the RF cavity synchronization as well as for RF beam feedback. This paper describes the LLRF concept of the RF beam phase feedback at SIS18 and presents results from machine experiments with beam where an adaptive feedback filter for damping longitudinal dipole oscillations during the whole SIS18 machine cycle was realized and successfully applied. Finally, an outlook will be given towards the full integration into the central control system and towards the SIS100 bunch-by-bunch longitudinal feedback system.
Paper: THPG33
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG33
About: Received: 14 May 2024 — Revised: 20 May 2024 — Accepted: 20 May 2024 — Issue date: 01 Jul 2024
THPG35
Generation of symmetrical optical caustic beams for precise alignment
3333
Generating layers of symmetrical optical caustic beams using a specific configuration of cylindrical lenses is an innovative idea with potential application in precision alignment and other fields. The technique allows the generation of layers of non-diffracting beams with opposite accelerating directions. This approach can be extended in two dimensions or to create rotationally symmetric beams. Prior methods have produced similar beams using spatial light modulators, but the presented approach with cylindrical lenses reduces setup complexity and cost, thereby opening the possibility for new applications. In the context of particle accelerators, these include particle acceleration using high-power lasers and alignment of accelerator components. The presented research emphasizes the possibility for this technique to be used as a reference line for precise alignment. It allows the generation of reference lines with a thickness in the order of millimeters for distances of tens to hundreds of meters, which is advantageous for large accelerator facilities. A brief description of the sensors used to detect misalignment is also presented.
Paper: THPG35
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG35
About: Received: 14 May 2024 — Revised: 22 May 2024 — Accepted: 24 May 2024 — Issue date: 01 Jul 2024
THPG36
Continuous position estimation for the full remote alignment system of the High Luminosity LHC upgrade
3337
The Full Remote Alignment System (FRAS) is an alignment system remotely controlled and monitored that comprises almost one thousand permanent sensors distributed along the 200 meters of equipment that will be installed in the frame of the High Luminosity LHC (HL-LHC) project on either side of the ATLAS and CMS detectors. The sensors, along with their electronics and a system of motorized actuators, will be used to adjust the relative positions of the components remotely, in real time, with no human intervention needed in the irradiated environment of the tunnel. In this contribution we describe the design and the implementation of the position estimation algorithm which is a core-component of the FRAS. This algorithm will process the data provided by all the sensors to determine exact positions and orientations of the associated components in real-time. The position estimation module is designed as a reusable C++ library and builds on the existing CERN LGC, a modular least-square software. It will be fully integrated into the FRAS software stack and is entirely file-less during operation. In this paper we will demonstrate its performance in a realistic case study and showcase its ability to provide position updates on a much higher frequency than the required 1 Hz.
Paper: THPG36
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG36
About: Received: 15 May 2024 — Revised: 17 May 2024 — Accepted: 18 May 2024 — Issue date: 01 Jul 2024
THPG37
Parallel quadrupole modulation for fast beam-based determination of magnet centers
3341
A method to simultaneously determine the magnetic centers of multiple magnets with beam-based measurements is proposed. Similar to the quadrupole modulation system (QMS) method that is widely used for beam-based alignment measurement, the strengths of the group of selected magnets are modulated. The orbit shifts induced by the modulation are used to deduce the kicks applied at the magnet locations with the help of orbit response matrix calculated with the lattice model. By varying the beam orbit at the magnets, with a pair of corrector of magnets or local orbit bumps, and repeating the modulation measurement at each orbit, the magnet centers can be determined through fitting the calculated kicks versus the beam orbit. Demonstration of the method on a storage ring is presented. The method can also been applied to nonlinear magnets.
Paper: THPG37
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG37
About: Received: 10 May 2024 — Revised: 19 May 2024 — Accepted: 19 May 2024 — Issue date: 01 Jul 2024
THPG38
Reducing background/noise in stretched wire alignment technique measurements
3345
The stretched-wire alignment technique is one method of magnet alignment for linear induction accelerators. The applications of the Stretched-Wire Alignment Technique (SWAT) have been implemented for aligning magnets/solenoids on the Scorpius linear induction accelerator which will be sited at the Nevada National Security Site and the Flash X-Ray (FXR) linear induction accelerator at Lawrence Livermore National Laboratory’s Contained Firing Facility. This article describes both systematic (repeatable) and random sources of background/noise as well as practical ways to either eliminate or mitigate them to acceptable levels. Systematic sources include reflections from wire ends, rapid sag due to ohmic heating of the wire, magnetic materials, and shot rate. Random sources include air currents, vibration of nearby equipment, mechanical stability of test equipment, and the instruments used to measure the wire motion. Mitigations include curve fitting and adaptive noise signal cancellation, and mechanical damping. Finite Element Analysis (FEA) was used to interpret results.
Paper: THPG38
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG38
About: Received: 15 May 2024 — Revised: 20 May 2024 — Accepted: 20 May 2024 — Issue date: 01 Jul 2024
THPG40
Time-of-flight beam loss monitor for the Advanced Photon Source Upgrade booster-to-storage-ring transport line
3348
We present initial results from the booster-to-storage-ring beam-loss monitor (BTSBLM) employing time-of-fight analysis to localize and minimize losses along the BTS line. The BTSBLM utilizes a pair of high-purity, fused silica fiber optic cables running in parallel along the 65-m BTS transport line. Photomultipliers located at both upstream and downsteam ends of each fiber monitor Cherenkov radiation generated by lost electrons. The downstream detectors receive temporally-compressed, higher-intensity, spatially-inverted signals, while the upstream waveforms are temporally expanded with lower intensity allowing finer time resolution; both upstream and downstream effects owing to the refractive index in the fiber glass. Each radiation-hard optical fiber is composed of 600, 660, and 710-micron-diameter core, cladding, and buffer and is similar to those used in the newly commissioned LCLS-II superconducting linac BLM system. Realtime waveforms are recorded on a fast oscilloscope and available for diagnostic observation through EPICS waveform records. Remote controlled high-voltage power supplies provide gain adjustment. Data from booster and storage-ring commissioning are presented.
Paper: THPG40
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG40
About: Received: 16 May 2024 — Revised: 22 May 2024 — Accepted: 22 May 2024 — Issue date: 01 Jul 2024
THPG41
CXLS ionizing and laser radiation safety interlock systems
3352
The Compact X-ray Light Source (CXLS) requires the acceleration of electron bunches to relativistic energies, which collide with focused IR laser pulses to produce X-rays which are then transported to the experiment hutch. A class 4 UV laser is used at the photocathode to liberate the electrons that are generated via the photoelectric effect. During electron acceleration bremsstrahlung radiation (gamma and neutron) is generated through electron interactions with solid matter. In the experiment hutch the X-rays then interact with the sample under test in pump-probe configuration where the pump laser is another class 4 laser with a wide spectral range from deep UV to THz. Interlock systems have been designed and deployed to protect users of the facility from exposure to these ionizing and laser radiation hazards. We present the design architecture of CXLS interlock systems. In this description we make clear what systems are independent, and which are interdependent and what administrative override modes are made available and why. We also provide an overview of our monthly interlock system testing protocols and conclude with comments on overall system performance.
Paper: THPG41
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG41
About: Received: 15 May 2024 — Revised: 20 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
THPG42
Radiation levels in the LHC tunnel and impact on electronics during the 2023 Pb ion run
3355
The 2023 operation of the Large Hadron Collider (LHC) at CERN included a one-month-long run with fully stripped Pb ion beams, marking the first heavy-ion run since 2018, and delivering Pb ion collisions at an unprecedented center-of-mass energy of 5.36 TeV per nucleon pair. During this period, the radiation fields in the LHC tunnel have been measured by means of different radiation monitors, including Beam Loss Monitors (BLMs), RadMons, and distributed optical fiber dosimeters, with the primary goal of quantifying the radiation exposure of electronic systems. The radiation levels are driven by the Bound Free Pair Production (BFPP) and Electromagnetic Dissociation (EMD) processes taking place in all four interaction points, yielding significant radiation peaks in the Dispersion Suppressor (DS) regions of the tunnel. An overview of the radiation levels is presented in this contribution, with a special focus on the Insertion Region 2 (IR2) hosting the ALICE experiment, where a new collimator (TCLD) has been installed specifically for the ion run. The impact of radiation on the electronic systems and on the LHC availability during the run will also be discussed.
Paper: THPG42
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG42
About: Received: 08 May 2024 — Revised: 22 May 2024 — Accepted: 22 May 2024 — Issue date: 01 Jul 2024
THPG43
Assessment of the ratios of radiation sources and total electron loss at the injection section of the Taiwan Photon Source facility and total electron loss by using neutron measurements
3359
Radiation in the injection section of a synchrotron radiation facility is primarily the result of injection beam loss, which occurs each time the current is replenished, and storage beam loss, which accounts for the lifetime during routine operations. This study conducted neutron measurements by using high-sensitivity neutron detectors and obtained the total electron loss during the unfolding process. With the known lifetime, the ratio of injection beam loss to storage beam loss and the total loss in the injection section of the Taiwan Photon Source facility during routine operations were determined. The total electron loss at the measurement site was approximately five millionths of the full load current. The ratio of injection beam loss to storage beam loss was 1.64. The total electron loss was 0.44 pC, with 0.27 pC being attributed to injection beam loss and 0.17 pC being attributed to storage beam loss.
Paper: THPG43
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG43
About: Received: 05 May 2024 — Revised: 16 May 2024 — Accepted: 17 May 2024 — Issue date: 01 Jul 2024
THPG44
The LCLS-II beam loss monitor readout system
3362
The Linac Coherent Light Source II (LCLS-II) is a new addition to the SLAC accelerator complex. It is a 4 GeV, 120 kW superconducting Linac operating in continuous RF mode at 1.3 GHz with a beam repetition rate of up to 1 MHz. The prior generation of protection system beam loss monitors, whose operation is based on ion collection principles, are not suitable for operation in LCLS-II due to their slow recovery times. A new group of detectors have been identified and evaluated. These fall into three categories: Cherenkov detectors using optical fibers and photomultiplier pickups for distributed losses. Point detectors based on diamond pickups, and YAG:ce screens with photodiode pickups for burn through detection. These new detector elements require that new readout and signal processing electronics to be developed. In addition, because these detectors are part of the SLAC Beam Containment System (BCS), a certified safety system, a self-check mechanism is required to continuously verify the health of the detector and readout. This paper describes the design, operation and performance of the readout electronics.
Paper: THPG44
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG44
About: Received: 15 May 2024 — Revised: 18 May 2024 — Accepted: 19 May 2024 — Issue date: 01 Jul 2024
THPG45
The onine radiation monitoring system for Hefei Advanced Light Facility
3366
An advanced online monitoring system with dual systems is being developing for Hefei Advanced Light Facility (HALF). One is based on the C language, which integrates data acquisition, storage and interface display. The other is based on EPICS system, which developed Input/Output Controller (IOC) and Operator Interface (OPI) for data acquisition and display. The two systems are based on Ethernet TCP / IP protocol for data communication, but they are independent. The on-line radiation monitoring system of Hefei Advanced Light Source (ORMSH) have the function of neutron and gamma dose monitoring and alarming. The ORMSH contains 160 monitors for workplace monitoring and environmental monitoring. Each monitor combines data collection, storage, automatic upload. two alarm methods will be adopted for dose interlocking in ORMSH: instantaneous dose rate alarming and cumulative dose alarming. This paper describes in detail the implementation of the system infrastructure and functions.
Paper: THPG45
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG45
About: Received: 15 May 2024 — Revised: 19 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
THPG46
Research on Monte Carlo model of radiation source in HLS storage ring
3369
Hefei Light Source (HLS) is the first dedicated synchrotron radiation facility in China. HLS-II operates in the TOP-OFF constant-current mode. For the safety of personnel, it is crucial to analyze the radiation fields applying Monte Carlo. The radiation source directly affects the results. The paper discusses the impact of three radiation source models on the radiation field results. In the first model, beam averaged losses over eight bend magnets. The second model assuming that there is a uniform loss at all beam pipes and bend magnets. The third model assumes that beam losses uniformly in a torus pipe. The radiation field during TOP-OFF constant-current of HLS-II storage ring was simulated applying FLUKA. The position and direction sampling equations were constructed for different radiation sources. Simulation results indicated that the dose rates of the second model was consistent to the torus uniform loss model. The calculation results of two models are in accord with the actual situation. As for the simulations on the radiation fields and radiation shield design in the storage ring, the torus radiation source with uniform loss is more convenient to operate.
Paper: THPG46
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG46
About: Received: 13 May 2024 — Revised: 24 May 2024 — Accepted: 24 May 2024 — Issue date: 01 Jul 2024
THPG47
Upgrade of LLRF control system for infrared free-electron laser
3372
Hefei Infrared Free-Electron Laser device (IR-FEL) is a user experimental device dedicated to energy chemistry research that can generate high brightness mid/far infrared lasers. It is driven by an S-band linear accelerator with a maximum electron energy of 60 MeV. The stability of the final output laser is determined by the energy stability and spread of the electron beam, and the Low-Level RF control system (LLRF) is opitimized to improve the energy stability of the electron beam. There are two klystrons in the linear accelerator of IR-FEL, and the periodic oscillation of out power output of the klytrons is existed (approximately ± 0.2%~2% for amplitude). The oscillation period of two klystrons are exchanged in the case of exchanging the filament power supplies of two klystrons. The pulse-to-pulse feedforward and in-pulse feedback algorithm are developed to compensate the periodic fluctuations of the output power of the klystrons, and the IQ demodulation is changed to the Non-IQ demodulation (13/3) to separate and suppress the odd harmonic. After the optimization, the stability of klystron output signal has been improved from 0.12%/0.07° (rms) to 0.04%/0.09° (rms).
Paper: THPG47
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG47
About: Received: 15 May 2024 — Revised: 19 May 2024 — Accepted: 22 May 2024 — Issue date: 01 Jul 2024
THPG48
Development of RF reference distribution system for Hefei Advanced Light Facility
3375
The Hefei Advanced Light Facility (HALF) is a diffraction-limited storage ring-based light source consists of a 180 m linear accelerator and a 480 m storage ring. The RF reference signal included 499.8 MHz and 2856 MHz are generated from two phase-locked master oscillators and transmitted to the RF system, beam position monitor system, timing system and beamline station by the phase stabled coaxial cables which are installed in the ±0.1℃ thermostatic bath. The RF Reference Distribution System (RF-RDS) are developed to realize the phase synchronization and transmission with low phase noise for long distance. The continues wave amplifier is manufactured to generate RF power of 10 W, with the added phase noise being less than 1 fs (10 Hz~10 MHz). The phase noise of each receiving terminal is estimated to be less than 30 fs (10 Hz~10 MHz). The design of RF-RDS and experimental result are discussed in this paper.
Paper: THPG48
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG48
About: Received: 15 May 2024 — Revised: 18 May 2024 — Accepted: 21 May 2024 — Issue date: 01 Jul 2024
THPG50
Lifetime studies of magnet protection systems for the Large Hadron Collider at CERN
3378
In the architecture of the protection of the superconducting magnets of the Large Hadron Collider (LHC), systems such as Quench Heater Discharge Power Supplies (HDS), Local Protection Interface Module (LIM), Linear Redundant Power Supplies (LPR), and Power Packs (LPUS) are crucial. Thousands of these devices, some in operation since 2007, directly impact LHC’s availability and reliability. This paper delves into comprehensive lifetime studies on these critical systems. The methodology involves estimating their remaining operational lifespan through detailed analyses of failure modes, assessing electronic component criticality, accelerated aging of electrolytic capacitors, inspections, and irradiation tests at both component and system levels. The study concludes by presenting essential findings, including the estimated remaining lifetime of each equipment. Additionally, the paper recommends future developments to enhance system robustness, offering valuable insights for maximizing the longevity of these critical devices. This research significantly contributes to ensuring the sustained reliability and performance of the LHC's magnet protection systems.
Paper: THPG50
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG50
About: Received: 15 May 2024 — Revised: 22 May 2024 — Accepted: 22 May 2024 — Issue date: 01 Jul 2024
THPG51
Design, manufacturing and validation of the CLIQ units for the protection of superconducting magnets for the High-Luminosity LHC project at CERN
3382
The novel Coupling-Loss-Induced-Quench (CLIQ) concept will be part of the quench protection system of the High Luminosity Large Hadron Collider (HL-LHC) Inner Triplet superconducting magnets at CERN. Several units of two distinct CLIQ prototype variants were produced to validate the CLIQ novel protection concept and define the system parameters for the required performance. Subsequently, these units were further enhanced by introducing additional redundancy, advanced monitoring systems, and improved safety features. These improvements culminated in the development of the third and final version. This paper provides insights into the evolution from prototypes to the final version to be installed in the machine, shedding light on the outcomes of comprehensive safety and electromagnetic compatibility (EMC) tests, coupled with extensive operational assessments.
Paper: THPG51
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG51
About: Received: 15 May 2024 — Revised: 21 May 2024 — Accepted: 22 May 2024 — Issue date: 01 Jul 2024
THPG52
Design, manufacturing and validation of the new quench heater discharge power supplies for the protection of superconducting magnets for the High-Luminosity LHC Project at CERN
3386
The Quench Heater Discharge Power Supplies (HDS) are magnet protection devices installed in the Large Hadron Collider (LHC) that, upon detection of a magnet quench, release energy into the copper-plated stainless-steel strip heaters, inducing a resistive transition all along the superconducting coils. Such a distributed internal heating ensures an even energy dissipation across the entire volume, preventing local overheating and magnet damage. Over 6000 HDS units have been operational in the LHC tunnel since 2007. The new HDS design for protection of the High Luminosity LHC (HL-LHC) Inner Triplet magnets, to be installed in the Long Shutdown starting in 2026, calls for a more advanced design with up-to-date components resulting in a higher reliability of the HDS units. Several HDS prototypes were produced at CERN, eventually culminating in the development of the HL-LHC HDS version to be installed in the accelerator. This paper describes the design of the upgraded HDS units and the comprehensive safety and electromagnetic compatibility (EMC) tests, coupled with extensive operational tests, including irradiation tests, that have been conducted.
Paper: THPG52
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG52
About: Received: 15 May 2024 — Revised: 20 May 2024 — Accepted: 20 May 2024 — Issue date: 01 Jul 2024
Early prediction of system failures at LANSCE
Particle accelerators are among the largest and most expensive scientific facilities. Constant monitoring of data from a diverse array of diagnostics is imperative to ensure proper operational parameters—such as beam parameters, power sources, cooling systems, etc. Detecting equipment failure within this data stream is challenging due to the accelerator parameters gradually shifting over time due to diverse user demands, environmental factors, and the feedback control system's operation. At LANSCE, identifying anomalies stemming from deteriorating equipment is a significant issue. To address this, we propose implementing an anomaly detection system based on existing machine learning algorithms. This system will monitor all available data for each accelerator subsystem, establish typical parameter ranges, and determine whether the measured parameters fall beyond those thresholds. This anomaly detection system aims to factor in intrinsic internal correlations among various parameters, which the current Data Watcher warning system fails to consider. We anticipate that this developed warning system will effectively identify ongoing equipment degradation and predict upcoming failures.
THPG56
The high-level software of the beam position limits detector system for the Advanced Photon Source upgrade storage ring
3390
A new Machine Protection System (MPS) and the Beam Position Limits Detector (BPLD) system are being developed for APS Upgrade (APS-U) accelerator storage ring. The MPS/BPLD system consists of one main MPS and 20 local MPS/BPLD controllers distributed around the ring, each local controller is located on every odd double sector. Each LMPS handles one double sector. Each double sector can be equipped up to seven Libera BPM electronics units. Each Libera unit processes up to four BPMs at Turn-by-Turn (TbT) rate. The Beam Position Limits Detector (BPLD) provides two types of protections: BPLD-ID and BPLD-BM for insertion device (ID) front-end (FE) and bending magnet (BM) incident radiation protection respectively. We select bumps using orbit feedback in a machine simulation to test the position limits of the system consistent with accelerator physics requirements for stable beam. This paper introduces the high level software implementation of APS-U BPLD-ID and BPLD-BM validation.
Paper: THPG56
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG56
About: Received: 15 May 2024 — Revised: 23 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
High-reliability and high-performance machine protection system for a demanding electron linac
LightHouse was a project utilizing a 3 MW electron linac to produce medical isotopes, requiring a very fast and reliable machine protection system to protect key accelerator components. RI Research Instruments GmbH designed the linac and conducted the risk analysis. This led to specifications to which Cosylab engineered a machine protection system (MPS). The MPS exhibits rapid responsiveness, with short reaction times on the order of 350 nanoseconds, while actively monitoring and reacting to approximately 700 inputs from crucial accelerator components. To enhance reliability and upgradeability, an FPGA solution based on the National Instruments platform was implemented. Additionally, the project envisions the integration of high availability storage and tertiary subsystems, with the overarching goal of achieving elevated uptime and ensuring the trustworthiness of all device elements.
THPG58
Radiation levels from a beam gas curtain instrument at the LHC at CERN
3393
A prototype Beam Gas Curtain (BGC) monitor was installed at the Large Hadron Collider (LHC) at CERN to provide 2D images of the transverse beam profile during the ongoing Run 3 (2022 to date) and in view of the High Luminosity LHC upgrade (HL-LHC). By design, the BGC operation generates collisions between the beam particles and an injected gas jet proportionally to the beam intensity and the gas density, possibly causing radiation-induced issues to the downstream LHC equipment. In this work, the radiation showers from the BGC are characterized using measured data from different LHC radiation monitors during the Run 3 BGC operation, along with Monte Carlo simulations with the FLUKA code. Finally, predictions of the expected radiation showers during the operation of the BGC in the HL-LHC era are discussed.
Paper: THPG58
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG58
About: Received: 10 May 2024 — Revised: 21 May 2024 — Accepted: 21 May 2024 — Issue date: 01 Jul 2024
THPG59
Testing aspects of the CERN beam interlock system prior to installation in the accelerator
3397
The Beam Interlock System (BIS) is the backbone of the machine protection system throughout the accelerator complex at CERN, from LINAC4 to the LHC. After 15 years of flawless operation, a new version of the BIS is currently being produced and will be installed in the LHC, SPS and North Area during CERN’s Long Shutdown 3, planned to start in 2026. Overall, more than 3,000 Printed Circuit Boards will be produced and assembled outside CERN. In addition, more than 120,000 lines of firmware and supporting scripts are written to implement the critical and monitoring functionalities of the BIS. Both hardware and firmware need to be thoroughly tested before installation and operation to guarantee the high levels of reliability and availability required by the operation of the accelerators. In this paper we present the testing methodology including the development of dedicated testbeds for hardware validation, the use of comprehensive simulation and continuous integration for firmware development, and the implementation of automated tests for system-level functional validation.
Paper: THPG59
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG59
About: Received: 06 May 2024 — Revised: 17 May 2024 — Accepted: 17 May 2024 — Issue date: 01 Jul 2024
THPG60
Development of a second-generation system for the reliable distribution of machine protection parameters
3401
The Safe Machine Parameter (SMP) system is an electronic hardware-based system which has been an integral part of the LHC’s machine protection strategy since it started operation. Its primary objective is to provide several parameters and interlock signals to critical machine protection users across the LHC and SPS accelerators, whilst prioritizing high reliability and availability. After almost two decades of operation, there is a need to upgrade the SMP hardware electronics. In the High Luminosity LHC era the requirements of connected systems have changed, leading to new system functions and operational requirements which must be integrated into the new design. This paper details the electronic design considerations of developing the second-generation SMP. The general distribution of parameters relies on the CERN WhiteRabbit timing network renovation, for which dedicated high-precision clock components were selected and tested on a prototype board. Details of the hardware design and validation are discussed, along with the comprehensive upgrades aimed at delivering an SMP system with expanded monitoring and diagnostic features.
Paper: THPG60
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG60
About: Received: 14 May 2024 — Revised: 23 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
THPG61
An approachable beam loss monitor configuration and operation tool for FRIB
3405
The folded Linear Accelerator (linac) at the Facility for Rare Isotope Beams (FRIB) presents many challenges to effectively utilizing beam loss monitors (BLMs) for machine protection. Dozens of ion chambers and neutron detectors are installed at various locations in the linac tunnel to monitor radiation from beam losses. Each device must be configured with thresholds to meet machine protection requirements for an array of beam destinations, ion species, beam energies, beam power, and response times. This presents an extremely large configuration space with numerous use-cases and beam modes to account for. We present a largely automated tool to effectively manage BLM thresholds that requires minimal input from operators.
Paper: THPG61
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG61
About: Received: 15 May 2024 — Revised: 18 May 2024 — Accepted: 18 May 2024 — Issue date: 01 Jul 2024
THPG62
FRIB target thermal image processing for accurate temperature mapping
3409
The FRIB carbon disc target receives the primary beam at high power and produces rare isotope fragments. To avoid damaging the carbon disc target, it is rotated at 500 RPM and cooled. If these thermal management mechanisms fail, local temperatures on the target can increase to the point of material sublimation and structural failure. A thermal imaging camera was temperature calibrated and installed for the purpose of monitoring the target temperature map in real time. Various image processing strategies were deployed to improve the accuracy and usefulness of the resulting image. Processing stages include conversion from intensity to temperature, median filtering to remove dead pixels, and flat field correction to compensate for vignetting and edge effects.
Paper: THPG62
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG62
About: Received: 15 May 2024 — Revised: 21 May 2024 — Accepted: 21 May 2024 — Issue date: 01 Jul 2024
THPG63
FPGA design of FRIB chopper monitor system
3413
In FRIB we use chopper in the low energy beam line for beam power controls. As appropriate functioning of chopper is critical for both beam operation and machine protection, an FPGA-based chopper monitoring system was developed to monitor its operation for fixed duty cycle operation and has been in use to support operation. The chopper monitor shuts off beam promptly at detection of a deviation of duty cycle outside tolerance. For future higher beam power operation, automatic beam power ramp modes will be required where beam duty factor is dynamically ramped up following a predetermined sequence. Recently FPGA prototype is developed to enhance the chopper monitor to accommodate one of such dynamic modes, cold start beam mode. It is a design challenge to integrate all the beam modes in one FPGA while synchronizing with external timing system pulse generator and recording the process data and failure information. Detailed FPGA design for this enhancement of chopper monitor will be discussed in this paper, followed by the test result of integrated system of chopper monitor, global timing system pulse generator, high voltage switch of chopper control and EPICS control software.
Paper: THPG63
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG63
About: Received: 15 May 2024 — Revised: 23 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
THPG64
Integration of LHC-type beam loss monitors into the machine protection system for the SIS100 synchrotron at FAIR
3417
The SIS100 heavy ion synchrotron is the central machine of the FAIR (Facility for Antiprotons and Ions Research) project at GSI. It presents complex challenges due to its features handling high-intensity ion beams from protons up to uranium. It demands sensitive beam diagnostics with robust Machine Protection Systems (MPS). Due to anticipated extreme conditions, one safety subsystem includes LHC-type Beam-Loss Monitors (BLMs). These BLMs play a critical role in beam diagnostics and machine safety, strengthening protection measures by enhancing monitoring capabilities for severe beam losses and triggering safe beam dump requests. These BLMs are gas chamber detectors which aim to prevent beam-induced quenching superconducting magnets and protect other machine components from damage. This document outlines a conceptual study of a Machine Protection System, integrating 168 LHC-type BLMs to safeguard the SIS100 synchrotron. The integration involves upgrading the readout electronic chain and adopting FPGA-based logic firmware to handle intricate rate counting requirements over specified time windows. Additionally, hardware sanity checks are carried out to prevent non-conformities and ensure reliability alongside beam loss rate counting. Overall, the focus on beam loss monitoring for the SIS100 within the FAIR project underscores the necessity for sophisticated diagnostic tools and protective measures to ensure the safe and efficient operation of this state-of-the-art synchrotron.
Paper: THPG64
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG64
About: Received: 15 May 2024 — Revised: 21 May 2024 — Accepted: 22 May 2024 — Issue date: 01 Jul 2024
THPG65
Equipment protection system against unexpected abnormalities during high-intensity proton beam operation at J-PARC MR
3420
The J-PARC MR synchrotron began high repetition operation with shortened accelerator cycles in 2022. So far, FX has been supplying a 2x10e+14 proton per pulse (ppp) beam to the Neutrino Experimental Facility with a repetition rate of 1.36 seconds, and SX has been supplying a 0.6x10e+14 ppp beam to the Hadron Experimental Facility with a 5.20 seconds repetition. The amount of heat per accelerated proton beam pulse exceeds 1 MJ, and it is an important issue to avoid damage to the equipment caused by high-intense beam due to abnormalities during beam acceleration. Since the MR is operated in different extraction modes, i.e. FX and SX, the countermeasures are also different, and the adequate protection system also needs to be considered, respectively. Therefore, the countermeasures have been put in place, including a high-speed beam abort system and/or a fast sequential interlock between devices. This report summarizes the systems to protect equipment from abnormalities that unexpectedly occur during high-intensity proton beam acceleration.
Paper: THPG65
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG65
About: Received: 14 May 2024 — Revised: 20 May 2024 — Accepted: 21 May 2024 — Issue date: 01 Jul 2024
THPG66
Machine protection system for TEX facility
3424
In the context of LATINO (Laboratory in Advanced Technologies for INnOvation) and Rome Technopole Projects founded by Regione Lazio and NextGenerationEu, and directly involved in the EuPRAXIA@SPARC_Lab flagship project, a testing facility for X-band (TEX) has been established at the Frascati National Laboratories of INFN. TEX is dedicated to the examination of radiofrequency X/C-band, aiming to develop and test the technologies and systems of a particle accelerator operating under such conditions. Given the complex nature of such a system and the advancement of technology to the forefront of the state of the art, it is imperative to have an advanced Machine Protection System (MPS) characterized by high reliability, availability, and safety, in accordance with IEC-61508 standards. Currently in development is a prototype MPS designed to autonomously initiate procedures to control operations and avert anomalies. An EPICS supervisor oversees the management of all devices and monitoring connected subsystems. Additionally, a real-time interlock system, based on distributed FPGA, is employed to swiftly respond to vacuum and RF systems during the next RF pulse.
Paper: THPG66
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG66
About: Received: 15 May 2024 — Revised: 22 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
THPG67
Modernization of DARHT axis-I debris blocker
3428
The Dual-Axis Radiographic Hydrodynamic Test Facility (DARHT) uses a spinning wheel debris blocker as a crucial machine protection system to prevent target debris from the electron to X-ray conversion process from traveling upstream and damaging the accelerator. The spinning wheel in use on DARHT Axis-I consists of two spinning disks normal to the beamline, each with an open slit that crosses the beamline at frequencies of 50 Hz and 40 Hz, creating an opening at a beat frequency of 8 Hz allowing the electron beam to pass through and shut behind it. In this poster, we present steps taken to improve the reliability and performance of the spinning wheel, which include replacing legacy and custom diagnostic components with off-the-shelf hardware. We also present the challenges and solutions in testing and deploying these upgrades without disrupting operation of the accelerator.
Paper: THPG67
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG67
About: Received: 15 May 2024 — Revised: 10 Jun 2024 — Accepted: 10 Jun 2024 — Issue date: 01 Jul 2024
THPG68
Coupling of codes for modeling high-energy-density conditions in fourth generation light sources
3431
We present a method for coupling particle dynamics, particle-matter interaction, and hydrodynamics codes to model the effects of high-intensity electron beams in Fourth Generation Storage Rings for the purpose of machine protection. The coupled codes determine if high-energy-density conditions (>100 J/mm^3) are present in beam-intercepting components. Elegant is used to simulate the dynamics of a whole-beam abort by muting the high-power cavity RF. Within the APS-U, the impacting beam begins interacting with a horizontal collimator, at which point elegant is interrupted and the beam impact process is modeled using MARS and FLASH. MARS simulates the interaction of the beam with the collimator, passes the energy density to FLASH, and returns the transmitted particle distribution to elegant. FLASH uses the energy deposition to determine the density of the collimator material. The surviving beam is propagated again through the APS-U lattice and the process is repeated until the beam is fully lost. The input MARS geometry is updated each step to reflect the changing material properties. The coupled codes also examine the effects of synchrotron radiation within the vacuum beam chambers.
Paper: THPG68
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG68
About: Received: 16 May 2024 — Revised: 24 May 2024 — Accepted: 24 May 2024 — Issue date: 01 Jul 2024
THPG69
Improvements of longitudinal stability with LLRF optimization at SIRIUS
3435
SIRIUS is a 4th generation synchrotron light source built and operated by the Brazilian Synchrotron Light Laboratory (LNLS). Recently, investigations of noise sources and the storage ring RF plant identification enabled a fine-tuning of the Digital Low-Level Radio Frequency (DLLRF) parameters. This paper presents the main improvements implemented, which include the mitigation of 60Hz noise from the LLRF Front End and the optimization of the control system parameters. Optimizations in the machine were based on an adjusted model of the SIRIUS storage ring RF plant. Tests with the model's parameters showed that the system's stability was strongly dependent on phase shifts introduced by nonlinearities from the high power RF sources. The new parameters significantly improved the control performance, increasing the bandwidth of the system and reducing longitudinal oscillations. BPM (Beam Position Monitor) and BbB (Bunch-by-Bunch) systems were employed to quantify longitudinal beam stability improvements.
Paper: THPG69
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG69
About: Received: 14 May 2024 — Revised: 20 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
THPG70
Canadian Light Source developments of the ALBA/CLS DLLRF system
3439
Located in Saskatoon, Saskatchewan, Canada, the Canadian Light Source (CLS) has been operation since 2003. CLS is a 3rd generation Synchrotron Light Source operating at 2.9GeV. The CLS Booster RF system uses a 100 kW, 500 MHz solid-state power amplifier to power two 5-cell “PETRA” cavities. Recently ALBA and CLS collaborated to commission a CLS-constructed version of the ALBA Digital Low-Level RF system in the CLS Booster ring RF system to replace the aging analog low-level RF system. Changes were required to address differing configuration and requirements between the CLS and ALBA RF systems. Challenges and opportunities for system machine safety, reliability, and performance improvements identified during and after commissioning have been addressed. Hardware configuration changes were implemented. Additional hardware devices have been produced and incorporated to streamline interfacing and to mitigate some risks.
Paper: THPG70
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG70
About: Received: 15 May 2024 — Revised: 20 May 2024 — Accepted: 20 May 2024 — Issue date: 01 Jul 2024
THPG71
Commissioning of the digital LLRF system at the KEK Photon Factory 2.5 GeV ring
3442
In 2023, the KEK-PF 2.5 GeV ring LLRF system was replaced from a conventional analog to an FPGA-based digital system. The hardware and software of our digital LLRF system were developed by customizing the LLRF technologies established at the SPring-8 and J-PARC. In our system, we adopted the non-IQ direct sampling method for RF detection. We set the sampling frequency at 8/13 (307.75 MHz) of the RF frequency, where the denominator (13) is the divisor of the harmonic number (312) of the storage ring. This allows us to detect the transient variation of the cavity voltage that is synchronized with the beam revolution. To compensate this voltage variation, we plan to implement a feedforward technique. These functions will be useful to improve the bunch lengthening performance in a double RF system for KEK future synchrotron light source. The new digital LLRF system has been already installed and used for the user operation. At the nominal beam current of 450 mA, the variation of the cavity voltage amplitude and phase were within ±0.06% and ±0.06°, respectively. In this presentation, we introduce the details of our new system and report on the commissioning results.
Paper: THPG71
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG71
About: Received: 10 May 2024 — Revised: 22 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
Status of the development of the new digital LLRF for ALBA synchrotron light facility
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 located in Barcelona. The design, implementation and tests are based on ALBA technical specifications. It is expected that the system will be tested on site, in its 500 MHz version, by summer 2024 while the 1.5 GHz (third harmonic version) will be tested on site by the first quarter of 2025. The architecture, design, and development as well as the performance of the LLRF system will be presented in this work.
THPG76
Improved beam loss accounting with fast data acquisition (DAQ) chassis
3446
Identifying the source of beam loss events in the CEBAF accelerator can be a challenging task. Determining whether an RF cavity with an unannounced gradient or phase transient is the culprit would be a valuable tool for operations staff in addressing recurring beam loss incidents. A prototype offline system was developed in the fall of 2022, utilizing a dispersive beam position monitor (BPM) and the existing switched electrode electronics BPM hardware. A commercial off-the-shelf data acquisition (DAQ) system was employed to capture BPM wire signals at a sample rate of 20 kS/s. The system was triggered by the fast shutdown signal, which disables the beam at the injector. Analysis of beam position and energy variation before a beam loss event was used to determine if the beam loss event was associated with an energy transient. The prototype system, implemented using National Instruments hardware and LabVIEW software, relied on a software trigger. Manual post-processing was required to ascertain whether the fault was due to an un-tripped cavity with a gradient or phase transient. This work presents a production-quality system that utilizes the same data acquisition hardware developed and installed in CEBAF to monitor the time domain RF control signals in the legacy analog RF systems. As the new system employs a hardware trigger, developing tools to automatically identify faults linked to energy transients unrelated to cavity faults will be straightforward.
Paper: THPG76
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG76
About: Received: 14 May 2024 — Revised: 17 May 2024 — Accepted: 17 May 2024 — Issue date: 01 Jul 2024
THPG78
AGS Booster model calibration and digital-twin development
3449
An accurate physics simulation model is key to accelerator operation because all beam control and optimization algorithms require good understanding of the accelerator and its elements. For the AGS Booster, discrepancies between the real physical system and online simulation model have been a long-standing issue. Due to the lack of a reliable model, the current practice of beam control relies mainly on empirical tuning by experienced operators, which may be inefficient or sub-optimal. In this work, we investigate two main factors that can cause discrepancies between simulation and reality in the AGS Booster: magnet misalignments and magnet transfer functions. We developed a orbit response measurement script that collects real machine data in the Booster for model calibration. By matching simulated data with real data, we can develop a more accurate simulation model for future polarization optimizations, and build the foundation for a fully functional digital-twin.
Paper: THPG78
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG78
About: Received: 15 May 2024 — Revised: 18 May 2024 — Accepted: 18 May 2024 — Issue date: 01 Jul 2024
THPG79
An automated quad scan based emittance measurement software
3453
Beam emittance plays the crucial role in a Beam transportation system. At a fixed-target beamline off the AGS Booster Synchrotron, beam emittance is determined through measuring the beam width via a segmented multi-wire ion chamber (SWIC) and varying quadrupole strength. The width of the beam signal (as Full Width Half Max) on the SWIC passes through a minimum value and the resulting dataset of FWHM per magnet current is used to fit a function. Using this technique, new controls software has been developed to set up measurements, acquire data, and perform analysis through a python-based scripts to calculate the emittance along the NASA Space Radiation Laboratory (NSRL) beamline. Initial results of the program are presented to for various points along the beamline in a variety of conditions.
Paper: THPG79
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG79
About: Received: 15 May 2024 — Revised: 21 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024
THPG81
HPSim simulation of the highly bunched WNR beam at LANSCE
3457
The linac at the Los Alamos Neutron Science Center (LANSCE) provides beam to five user facilities with various beam energy and timing patterns. While the other four facilities have the same 201.25-MHz micro-bunch structure created by a pre-buncher and main-buncher pair, the Weapon Neutron Research (WNR) requires significantly higher charge per micro-bunch. This is achieved via adding a low frequency buncher at 16.77 MHz to the Low Energy Beam Transport. Such highly bunched micro-bunches create several challenges in operation and remain a critical capability to maintain for the LANSCE Modernization Project. We will demonstrate the HPSim simulation of the WNR beam through the LANSCE linac as a tool to address these issues in the future.
Paper: THPG81
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG81
About: Received: 14 May 2024 — Revised: 20 May 2024 — Accepted: 21 May 2024 — Issue date: 01 Jul 2024
THPG82
Using a particle-in-cell model for accelerator control room applications
3461
Many accelerator control rooms rely on envelope models to simulate beam dynamics because they are fast and accurate at tracking the beam core. Particle-in-Cell (PIC) models, however, can track particles inside and outside the core and, with the improvements of computers, are now fast enough to be used in control rooms. The Spallation Neutron Source (SNS) at Oak Ridge National Laboratory is currently developing a tool to use a Particle-in-Cell model for control room applications. This report covers the progress so far and the future goals of using PyORBIT, a Particle-in-Cell simulation model, in the SNS control room.
Paper: THPG82
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG82
About: Received: 15 May 2024 — Revised: 19 May 2024 — Accepted: 21 May 2024 — Issue date: 01 Jul 2024
An online analysis platform to facilitate analysis at X-ray light source
The design, execution, and analysis of light source experiments requires the use of sophisticated simulation, controls and data management tools. Existing workflows require significant specialization to accommodate specific beamline operations and data pre-processing steps necessary for more intensive analysis. Recent efforts to address these needs at the National Synchrotron Light Source II (NSLS-II) have resulted in the creation of the Bluesky data collection framework, an open-source library for coordinating experimental control and data collection. Bluesky provides high level abstraction of experimental procedures and instrument readouts to encapsulate generic workflows. We present a prototype analysis platform for coordinating data collection with real time analysis at the beamline. Our application leverages a flexible run engine to execute user configurable Python-based analyses with customizable queuing and resource management. We discuss initial demonstrations to support X-ray photon correlation spectroscopy experiments and future efforts to expand the platform's features for adaptive and machine-learning informed workflows.
THPG84
3D visualization and analysis of neutron scattering data in the control room
3465
Neutron scattering experiments have undergone significant technological development through large area detectors with concurrent enhancements in neutron transport and electronic functionality. Data collected for neutron events include detector pixel location in 3D, time and associated metadata, such as sample orientation and environmental conditions. Working with single-crystal diffraction data we are developing both interactive and automated 3D analysis of neutron data by leveraging NVIDIA’s Omniverse technology. We have implemented machine learning techniques to automatically identify Bragg peaks and separate them from diffuse backgrounds and analyze the crystalline lattice parameters for further analysis. A novel CNN architecture has been developed to identify anomalous background from detector instrumentation for dynamical cleaning of measurements. Our approach allows scientists to visualize and analyze data in real-time from a conventional browser, which promises to improve experimental operations and enable new science. We have deployed a cloud based server, leveraging Sirepo technology, to make these capabilities available to beamline users in the control room.
Paper: THPG84
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG84
About: Received: 15 May 2024 — Revised: 04 Jun 2024 — Accepted: 04 Jun 2024 — Issue date: 01 Jul 2024
THPG85
Updates to Xopt for online accelerator optimization and control
3469
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, DESY, ESRF, and others. In this work, we describe updates to the Xopt framework that expand its capabilities and improves optimization performance in solving online optimization problems. We also discuss how Xopt has been incorporated into the Badger graphical user interface that allows easy access to these advanced control algorithms in the accelerator control room. Finally, we describe how to integrate machine learning based surrogate models provided by the LUME-model package into online optimization via Xopt.
Paper: THPG85
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG85
About: Received: 15 May 2024 — Revised: 22 May 2024 — Accepted: 22 May 2024 — Issue date: 01 Jul 2024
Machine learning for the LCLS-II injector online modeling and optimization
The LCLS-II is a high repetition rate upgrade to the Linac Coherent Light Source (LCLS). The emittance and dark current are both critical parameters to optimize for ideal system performance. Here we summarize the role these tools played in the commissioning period and are playing in the current operational stage of the LCLS-II injector, which provides an example of how other accelerator facilities may benefit from combining online modeling and optimization infrastructure. We also describe current progress on creating a fully deployed digital twin of the LCLS-II injector based on a combination of ML modeling and physics modeling, using the LUME software suite and various ML-based characterization tools. Finally, we will describe current efforts and plans to leverage the online LCLS-II injector model in fast optimization and control schemes.
THPG87
Autofocusing accelerator beams
3473
A novel tuning approach, Model Coupled Accelerator Tuning (MCAT), has been applied to the separated function DTL at TRIUMF's Isotope Separator and Accelerator (ISAC). A digital twin of the rare-isotope postaccelerator is used for transverse and longitudinal tune optimizations, which are then loaded directly into the control system. Beam-based testing produced accelerated beam with a 0.26% error in output energy, with a 1.6% energy spread. This method significantly reduces the operational complexity of tuning interventions, rendering them more efficient. An analysis of the high energy beam lines (HEBT) is also presented, including analysis of dispersive couplings in certain sections of the beamline. A mitigation strategy involving buncher cavities is discussed.
Paper: THPG87
DOI: reference for this paper: 10.18429/JACoW-IPAC2024-THPG87
About: Received: 15 May 2024 — Revised: 23 May 2024 — Accepted: 23 May 2024 — Issue date: 01 Jul 2024