controls
MOP1040
Sensitivity of FCC-ee beam performance to resonance driving terms in the presence of beam–beam interactions
149
The control of nonlinear beam dynamics is essential for achieving the luminosity targets of FCC-ee, particularly in the presence of strong beam–beam interactions and machine imperfections. Resonance Driving Terms (RDTs) provide a systematic framework to characterize nonlinear dynamics and quantify the strength of resonances excited by nonlinear magnetic elements in the lattice. This contribution presents a sensitivity study of individual RDTs and their impact on beam losses, vertical emittance, and luminosity in FCC-ee, evaluated using tracking simulations including beam–beam interactions. The results establish a ranking of the relative importance of individual RDTs on the performance, providing guidance for future RDT-based correction strategies.
Paper: MOP1040
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP1040
About: Received: 13 May 2026 — Revised: 18 May 2026 — Accepted: 18 May 2026 — Issue date: 22 May 2026
MOP1066
Probing the ultimate beta* reach of the LHC
209
In 2026, the Large Hadron Collider will conclude its final operational run, before being upgraded to the High-Luminosity Large Hadron Collider during the following long-shutdown. Originally conceived with a nominal beta* of 0.55m in both planes, over successive years, its optics design has been steadily pushed beyond those initial goals, with round optics down to 0.25m/0.25m (2018), and flat optics down to 0.6m/0.18m (2025) used in operation. In 2025, dedicated beam-studies were performed to test the viability of controlling beta* waist errors at such low-beta*, and to explore the viability of squeezing and commissioning the optics even further. Possible operational scenarios for 0.5m/0.15m and 0.4m/0.12m were tested, and optics measurements down to a potential minimum beta* of 0.07m achieved. The outcome of these tests will be presented.
Paper: MOP1066
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP1066
About: Received: 13 May 2026 — Revised: 22 May 2026 — Issue date: 22 May 2026
MOP1099
Powering Concepts for Resistive Magnets in the Muon Collider Rapid Cycling Synchrotron
284
The development of a power converter for the resistive magnets of the Muon Collider Rapid Cycling Synchrotron (RCS) represents one of the most critical challenges of the muon accelerator system, given the required peak power levels in the 50–100 GW range. To address this, a modular resonant converter is proposed, consisting of several hundred identical series-connected cells interleaved with the magnets. This configuration distributes the total system voltage — on the order of tens of megavolts — evenly across the cells, while limiting the insulation voltage to ground. A key design requirement is a highly repeatable current ramp across successive pulses, with deviations at or below 100 ppm. Given the very short acceleration times, a pulse-to-pulse Iterative Learning Control (ILC) strategy is proposed to progressively meet this target. The paper presents the main converter topologies, repeatability studies, simulation results, and the proposed control approaches.
Paper: MOP1099
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP1099
About: Received: 23 Apr 2026 — Revised: 06 May 2026 — Accepted: 16 May 2026 — Issue date: 22 May 2026
MOP6001
Eliminating mains noise effects in accelerators with Machine Learning
341
Power supply ripples at various frequencies - characteristic to the magnet circuits or from the electrical network - have always been an issue in accelerator operations, with several mitigation measures put in place over the years. This contribution summarises the efforts in the CERN SPS over the last years to compensate the ripple at 50 Hz and its harmonics in the main quadrupole circuits, using Machine Learning methods. The detrimental effects of the ripple at low energy for LHC-type beams and at top energy for slow extracted beams are introduced. For optimal conditions of slow extracted beams, a continuous control algorithm had to be conceived. The implementation required hardware modifications on the power converter electronics side, additional new controls infrastructure and the development of adaptive algorithms that can deal with changes in the electrical distribution network throughout the day. Continuous control with tailored adaptive Bayesian Optimisation has been implemented for slow extracted spill control throughout 2024 and 2025. The improved spill quality obtained over the years will be discussed. Finally, results from R&D towards one-shot correction algorithms for beams that are only played on-demand (i.e. LHC beams) will also be briefly summarised.
Paper: MOP6001
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6001
About: Received: 11 May 2026 — Revised: 22 May 2026 — Issue date: 22 May 2026
MOP6302
APS-RAG: A domain-aware hybrid retrieval augmented generation system for accelerator operations and knowledge synthesis
345
Effective knowledge management is essential to minimize downtime and maintain institutional memory in large-scale accelerator facilities. We present APS-RAG, a domain-aware Retrieval-Augmented Generation (RAG)\* system currently deployed at the Advanced Photon Source (APS), designed to synthesize operational intelligence and facilitate semantic data retrieval from various dispersed databases. The system consolidates over 10,000 unique documents from four live databases: the BELY scientific electronic logbook, operational Microsoft Teams chat, the Integrated Content Management System (ICMS), and Work Request system. By employing the latest frontier LLMs via Argonne’s ARGO AI platform, APS-RAG integrates a specialized query preprocessing pipeline that performs temporal parsing, domain acronym resolution, multi-query expansion, and final response generation. To ensure high precision, a hybrid retrieval architecture is utilized, combining dense vector and keyword search. The results are aggregated using Reciprocal Rank Fusion (RRF) and refined through cross-encoder reranking to maximize relevance\*\*. An 100-question evaluation dataset was built using InPars methodology\*\*\*, supplemented with qualitative user feedback. The final responses from APS RAG have inline citations embedded which displays the source document chunk and a web accessible link to the original document. Future developments include multimodal integration and agentic knowledge graph capabilities\*\*\*\*.
Paper: MOP6302
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6302
About: Received: 13 May 2026 — Revised: 15 May 2026 — Accepted: 16 May 2026 — Issue date: 22 May 2026
MOP6307
Online tuning of the NSLS-II injector using Bayesian optimization with different packages
352
The injector of the NSLS-II consists of a linear accelerator (LINAC) that accelerates the electron beam to 170 MeV, followed by a linac-to-booster (LTB) transport line and a booster synchrotron that further increases the beam energy to 3 GeV. The performance of LINAC and LTB is critical to achieve efficient and stable beam injection. Automated online tuning is an effective method to improve injector performance. In this paper, we present an automated tuning approach based on Bayesian optimization, using different software packages to optimize the LINAC and LTB. We evaluate and compare these packages based on their ability to improve injection efficiency. Our results demonstrate that Bayesian optimization can significantly enhance injector performance and show differences in performance between different packages.
Paper: MOP6307
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6307
About: Received: 13 May 2026 — Revised: 17 May 2026 — Accepted: 20 May 2026 — Issue date: 22 May 2026
MOP6310
Machine-Learning–Assisted Bayesian Uncertainty Quantification for Accelerator Digital Twin Modeling and Control
355
Digital twins of particle accelerators are increasingly used for experiment planning, machine studies, and model‑based control. Achieving high‑fidelity predictions requires knowledge of machine properties that are difficult to measure directly, such as magnet alignments, transfer function variations, nonlinearities, and stray fields. In this work, we introduce parameterizations to capture these effects and employ Bayesian inference to estimate their values and uncertainties by calibrating a digital twin to orbit response measurements from the AGS Booster at Brookhaven National Laboratory. A machine‑learning emulator trained on a perturbed ensemble of Bmad simulations enables computationally efficient sampling of the high‑dimensional posterior. The resulting joint parameter distribution incorporates BPM uncertainties and provides data‑constrained variations that, when inserted back into the digital twin, significantly improve agreement with measured beam orbits while yielding uncertainty estimates on both parameters and predictions.
Paper: MOP6310
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6310
About: Received: 11 May 2026 — Revised: 15 May 2026 — Issue date: 22 May 2026
MOP6311
AI-ready lattice representation and ML optimization for the BNL booster-to-AGS transfer line
359
As part of the Nuclear Physics AI-Ready Accelerator Data (NARAD) project, Brookhaven National Laboratory is developing a demonstration use case based on the Booster-to-AGS (BtA) transfer line. We establish an AI-ready representation of the BtA lattice using the Particle Accelerator Language Standard (PALS), extended with semantic metadata linking lattice elements to control system signals and device capabilities. This NARAD-PALS model enables direct mapping between simulation, operational devices, and machine data. We implement this framework for the BtA line and demonstrate semantic device queries and control-channel resolution within the BNL Accelerator Device Objects (ADO) system. This unified representation supports integration of streaming and archived data and provides a foundation for ML-based optimization of AGS injection and cross-facility interoperability.
Paper: MOP6311
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6311
About: Received: 12 May 2026 — Revised: 15 May 2026 — Accepted: 16 May 2026 — Issue date: 22 May 2026
MOP6317
Accelerator performance drift compensation with a modified MG-GPO Algorithm
370
Performance drift has been a longstanding problem for accelerators. A desirable solution is to tune the machine slowly and gently to compensate for such drift. Previously, we presented a version of the Multi-Generation Gaussian Process Optimizer which tunes accelerator settings during operation to maintain optimal performance. In this paper, we present an improved version of the algorithm and its application test examples, in which it corrects deviations from the ideal orbit caused by a drifting orbit corrector magnet and a drifting injection kicker magnet respectively. The modified algorithm takes measures to ensure the accuracy of the Gaussian process regression models and to improve the validity of the new trial solutions. We demonstrate that this is a promising development toward using safe, real-time tuning algorithms during accelerator programs to compensate for performance drift.
Paper: MOP6317
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6317
About: Received: 17 May 2026 — Revised: 20 May 2026 — Issue date: 22 May 2026
MOP6321
Evaluating in-context learning for Advanced Light Source EPICS process variable prediction
381
Large language models are becoming increasingly relevant for accelerator operations, where they assist with common tasks like retrieving historical data, preparing analysis scripts, and coordinating multi-step procedures. At the Advanced Light Source (ALS), these operators use their personal jargon (e.g. “sector 4 beam current”) to search for the correct PV name from numerous channels, resulting in countless variations of naming conventions. Strong scores on general-purpose benchmarks do not indicate how well a model maps operator jargon to facility-specific EPICS process variable~(PV) identifiers. Building on the semantic channel-finding benchmark, we evaluate chat-based large language models on two tasks using 101 ALS expert query–PV pairs. The first probes query-level grounding via single-item testing. The assessment is executed with varying inference-time cues, scored by character-wise correspondence (Levenshstein ratio). The second probes structural understanding by requiring the model to infer character-sequence mapping from the global naming-token vocabulary under prescribed edge-count budgets. We report precision, recall, combined retrieval score (F1), and token overlap (Jaccard similarity). Applied to 27 models, these evaluations split PV retrieval from structural understanding of hierarchical naming patterns, and offer strong dependency of end-to-end PV identification on the ALS control system's naming conventions.
Paper: MOP6321
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6321
About: Received: 15 Apr 2026 — Revised: 16 May 2026 — Accepted: 16 May 2026 — Issue date: 22 May 2026
MOP6322
Status of Osprey: A Framework for Agentic AI in Control Systems
385
Operating large-scale scientific facilities requires coordinating diverse subsystems, translating operator intent into precise hardware actions, and maintaining strict safety oversight. Language-model agents offer a natural interface for these tasks, but most existing approaches are not yet reliable or safe enough for production use. We introduce Osprey, a framework that wraps a coding agent in a control-room operator interface, a tool surface that reaches hardware through pluggable connectors for the control system used in our community, and a first-class component for natural-language search of facility electronic logbooks. The agent itself is treated as a replaceable component: operator interface, safety policy, tool servers, and connectors stay under facility control, while the agent backend can be swapped as the AI ecosystem evolves. A declarative build-profile mechanism lets each facility maintain its own configuration without forking the shared framework, keeping deployments reproducible across updates. Osprey has been deployed at several DOE accelerator facilities through the MOAT seed effort within the Genesis~Mission. This paper presents the current framework architecture and reports on the substantial evolution Osprey has undergone over the past year.
Paper: MOP6322
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6322
About: Received: 17 May 2026 — Revised: 22 May 2026 — Issue date: 22 May 2026
MOP6336
Active supervision for AGS bunch-merging with LLM-based reinforcement learning
392
Radio-frequency (RF) bunch-merging gymnastics is used in the RHIC heavy-ion program to combine individual source pulses into single bunches with suitable intensity. Preserving intensity and emittance during these gymnastics requires careful coordination of the voltages and phases of RF cavities at several harmonic numbers, which is labor-intensive and fragile against machine drift. Recent work using a physics-based simulator of the Brookhaven Alternating Gradient Synchrotron (AGS) has shown that reinforcement learning (RL) can learn effective merge configurations. RL is data-intensive and requires many training interactions with the environment. Large language models (LLMs) have recently demonstrated the ability to extract patterns from large, noisy data and to integrate domain knowledge into the control loop, making them an attractive aid for tuning complex accelerator systems. However, domain adaptation (i.e., prompt engineering, finetuning, etc.) is always required for deploying LLM in the target domain and has not been investigated in particle accelerators. To fill this gap, we propose an active supervision framework in which the LLM-based teacher first transfers general control principles from human operators to the student agent. Then, the student agent further finetunes the control policy by interacting with the simulator/experiments with improved sample efficiency.
Paper: MOP6336
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6336
About: Received: 13 May 2026 — Revised: 20 May 2026 — Issue date: 22 May 2026
MOP6338
Beam-Based Characterisation of BPM Electronics Thermal Sensitivity after Two Decades of Operation
396
Beam-based measurements of the thermal sensitivity of beam position monitor (BPM) electronics were performed in SPEAR a third-generation storage ring after more than twenty years of routine user operations. Controlled building-temperature excursions were applied to two equipment buildings containing key BPM front-end and digitiser racks. Using orbit- and charge-normalised BPM signals and independent temperature logging, we performed lag-aware regression to estimate effective position-versus-temperature coefficients for each BPM, and compared several alternative temperature-driver models (global, per-building and hybrid). The method was applied to two measurement campaigns, months apart, with different ambient conditions. The results show clearly distinguishable building-level responses and reproducible patterns within subsets of BPMs, but also highlight strong correlations between temperature, beam conditions and slowly varying lattice effects. We present this analysis framework as a step towards robust, beam-based thermal characterisation of ageing BPM systems, and outline how extended datasets could support future BPM upgrades, thermal monitoring and operational orbit-stability tools.
Paper: MOP6338
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6338
About: Received: 13 May 2026 — Revised: 15 May 2026 — Accepted: 16 May 2026 — Issue date: 22 May 2026
MOP6375
Integration of X-Ray Diagnostics into Fast Orbit Feedback for Local Source Stabilization at NSLS-II
434
We present an accelerator-based X-ray beam stabilization approach that integrates X-ray beam position monitor (XBPM) signals into the fast orbit feedback (FOFB) system at NSLS-II. A high-speed electrometer and fiber-optic data link were developed to transmit XBPM position data to the storage-ring feedback controller at a 10 kHz rate. On the accelerator side, the XBPM signal is incorporated into the FOFB infrastructure as a virtual beam position monitor, allowing photon beam motion to be corrected through the electron beam orbit using fast corrector magnets. Experimental tests demonstrate suppression of dominant beamline vibration peaks near 27 Hz and 120 Hz when the feedback is enabled. These results demonstrate the feasibility of integrating photon diagnostics into accelerator feedback systems for improved X-ray beam stability and motivate the development of unified photon–electron feedback architectures for routine operation.
Paper: MOP6375
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6375
About: Received: 06 Apr 2026 — Revised: 14 May 2026 — Accepted: 16 May 2026 — Issue date: 22 May 2026
MOP6376
Test-bench measurement of power-supply, magnet, and vacuum-chamber bandwidth at NSLS-II
436
In 2019, the NSLS-II fast orbit feedback (FOFB) system was upgraded by reducing BPM and Cell Controller latency, increasing the closed-loop bandwidth from about 250 Hz to 400 Hz. The dynamic behavior of the power supply, magnet, and vacuum chamber, however, had not been directly measured and was treated as a lumped delay. To provide baseline parameters for the NSLS-IIU upgrade, we developed a dedicated test bench and remeasured these components. The existing fast-corrector power supplies show bandwidths of about 4.5 kHz horizontally and 1.5 kHz vertically, while the magnet and chamber responses are near 10–15 kHz with an overall response time of about 10 µs. We also characterized a newer power-supply regulator design and tuned it to achieve a 6 kHz bandwidth in both planes for use in the upgraded FOFB system. Incorporating these measurements into a physics-based model yields good agreement with observed system behavior. These results provide the first full experimental characterization of the fast-corrector chain at NSLS-II and establish the baseline for designing next-generation hardware for NSLS-IIU.
Paper: MOP6376
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6376
About: Received: 18 Apr 2026 — Revised: 15 May 2026 — Accepted: 18 May 2026 — Issue date: 22 May 2026
MOP6380
Facility-wide monitoring and early detection of failures at LANSCE
442
Accelerator complexes contain tens of thousands of interdependent components, and aging infrastructure amplifies the risk of equipment faults and costly, unscheduled shutdowns. At the Los Alamos Neutron Science Center (LANSCE), we are developing a data-driven framework that flags developing problems early enough to address them during scheduled maintenance, thereby improving reliability and increasing beam availability for users. Our approach analyzes all available signals within a subsystem to learn the facility’s “normal” operating envelope and to detect subtle deviations that precede failures. Unlike the current warning scheme, it captures hidden correlations among parameters and generates interpretable indicators of abnormal behavior. Predictions are validated against historical control-room log records. We report progress on three fronts: (i) extending anomaly prediction from a single beamline to all major LANSCE subsystems; (ii) expanding data archiving capacity by an order of magnitude to support broader coverage and longer look-back windows; and (iii) developing operator-facing algorithms that both warn of emerging anomalies and localize likely problem elements along the beamline. Together, these advances are designed to shift maintenance from emergency response to planned intervention, reducing downtime and enhancing overall facility performance.
Paper: MOP6380
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6380
About: Received: 11 May 2026 — Revised: 19 May 2026 — Accepted: 20 May 2026 — Issue date: 22 May 2026
MOP6385
Development of a low-level RF system for the Sirius passive 3rd-harmonic cavity based on MTCA.4 platform
450
The SIRIUS storage ring RF system currently operates with two 500 MHz superconducting cavities, each powered by a 130 kW RF plant composed of two solid-state amplifiers (SSA) and a 200 mA beam current. A passive 2-cell superconducting 3rd-harmonic cavity (3HC) is planned for installation in 2027 to increase beam lifetime through bunch lengthening and allow the beam current to be increased to the nominal value of 350 mA. This paper presents the current status of the development of a Low Level RF (LLRF) system for the 3HC based on MTCA.4 platform. The system includes a dedicated analog front-end for RF signal acquisition and conditioning, as well as clock and local oscillator (LO) generation. The digital hardware is based on Struck MTCA modules and an additional digital front-end for external signal isolation and interface with the FPGA GPIOs. Finally, the proposed DSP chain for cavity signal processing and control is presented and discussed.
Paper: MOP6385
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6385
About: Received: 13 May 2026 — Revised: 15 May 2026 — Accepted: 17 May 2026 — Issue date: 22 May 2026
MOP6388
Python-EPICS RF Conditioning Automatic Control System at the Spallation Neutron Source
454
The RF Test Facility (RFTF) at the Spallation Neutron Source (SNS) is used for RF conditioning of components such as ceramic windows and couplers prior to their installation in charged-particle accelerators. This process involves exposing components to high-power RF fields and thermal cycling to improve performance and remove impurities. To automate and optimize this process, a Python-based EPICS control system was developed, along with hardware upgrades. The system enables real-time monitoring and control of RF power levels, temperature, and vacuum pressure. A user-friendly graphical interface was implemented using CS-Studio (Phoebus), allowing operators to adjust parameters and collect data efficiently. The system integrates the High Power Protection Module (HPM) for interlocks based on vacuum and arc detection, ensuring safe operation. These upgrades have significantly improved the efficiency, accuracy, and safety of RF conditioning at the SNS RFTF. This presentation introduces the updated RF conditioning system, highlighting the software and hardware developments, and its application in support of the Proton Power Upgrade (PPU) project at SNS.
Paper: MOP6388
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6388
About: Received: 05 May 2026 — Revised: 15 May 2026 — Accepted: 16 May 2026 — Issue date: 22 May 2026
MOP6389
High-power test and system integration of direct RF sampling based LLRF control and monitoring system for S-band accelerating structures
457
High precision Low-level RF (LLRF) control and monitoring systems for future particle accelerators will be a significant technical challenge as the requirements in performance, flexibility and affordability become increasingly stringent. We have developed an RF system-on-chip (RFSoC) based next generation LLRF (NG-LLRF) for S-band accelerating structures, which samples and synthesizes the RF pulses directly without the analog mixers used for traditional LLRF systems. The platform delivered considerably better performance than the requirements of the targeted applications, such as the upgrades for Next Linear Collider Test Accelerator (NLCTA) and test facilities at SLAC. As part of the upgrade program, we also developed a custom solid-state amplifier (SSA) to deliver RF pulses at desired power level of the klystron. The integration of the LLRF with SSA and the high-power test facility could be challenging. The power levels and RF pulse stability at each stage of the high-power RF drive system need to be optimized to deliver the desired RF performance. In this paper, the integration procedure and the test and characterization results at each stage of integration will be summarized, analyzed and discussed. This integration is an essential step for the full deployment of the NG-LLRF system to the test facilities and accelerators in different frequency bands.
Paper: MOP6389
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6389
About: Received: 18 Apr 2026 — Revised: 14 May 2026 — Issue date: 22 May 2026
MOP6393
Longitudinal phase space diagnostics for the AGS
465
The Collider-Accelerator Department (C-AD) maintains and operates an injector complex that provides beams for the Relativistic Heavy Ion Collider (RHIC) and the future Electron-Ion Collider (EIC). Beams traveling in accelerator rings are grouped in bunches, where their profiles can be measured and displayed by a Wall Current Monitor (WCM). By analyzing those WCM signals, conclusions can be made about the beam quality, and necessary tuning can be performed accordingly. Meanwhile, it will be very helpful to have the beam property parameters available while doing beam experiments, such as the longitudinal emittance, momentum spread, bunch length, etc. In this work, we present such a software tool that will process and publish those parameters in real time, based on live machine data and WCM signals. Those parameters will also be logged to the system and will be available for later retrieval and analysis.
Paper: MOP6393
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6393
About: Received: 12 May 2026 — Revised: 20 May 2026 — Issue date: 22 May 2026
MOP6394
Progress in the development of the community Particle Accelerator Language Standard (PALS)
469
The Particle Accelerator Language Standard (PALS) is a community effort to create an open standard to promote lattice information exchange for particle accelerators. PALS development is a community-wide international effort involving accelerator physicists from multiple institutions. While it started as a lattice standard for beam dynamics simulations, it is now being extended to support other particle accelerator activities, in particular accelerator operation. With new accelerators that are becoming more complex, larger collaborations and the increasing imprint of artificial intelligence in all accelerator activities (from design to operation to workforce development), the imperative for a common, standardized accelerator ontology has been transitioning from “nice-to-have” to “must-have”. We will present the status of the project, its relations to other projects, including to two of the particle accelerator projects of the newly announced US DOE Genesis Mission: the Multi-Office Accelerator Team (MOAT) project and the Nuclear physics AI-Ready Accelerator Data (NARAD) project.
Paper: MOP6394
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6394
About: Received: 14 May 2026 — Revised: 15 May 2026 — Issue date: 22 May 2026
MOP6612
Waveform pattern control of the paint bump power supply for the J-PARC RCS using neural networks
481
The J-PARC RCS uses four horizontal and two vertical painting magnets to generate a high-intensity beam through painting injection. Their IGBT-chopper power supplies can reproduce current waveforms with an accuracy of better than 1%. Combining automatic generation of input voltage (IV) patterns with manual fine-tuning keeps the current deviation of the painting pattern (PP) within ±0.2%. There are 90 waveform patterns in total, including two types: trapezoidal patterns for low-beam-loss studies and painting patterns for high-intensity beam production. As these patterns have different current demands and impose different loads on the power supplies, the tuning process becomes increasingly complex. Adjusting one PP takes approximately one hour and optimising all 90 patterns takes several days; therefore, reducing the adjustment time is essential. To address this issue, a neural-network (NN) approach was applied to generate optimized IV patterns. Training the NN with existing IV data yielded highly accurate voltage patterns, improving PP reproducibility. This presentation reports on NN-based waveform optimisation and its application to beam operation.
Paper: MOP6612
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6612
About: Received: 01 Apr 2026 — Revised: 15 May 2026 — Issue date: 22 May 2026
MOP6623
Software development of beam diagnostics readout system based on a multi-channel high-speed digitizer
501
In the upgraded accelerator of the China Spallation Neutron Source Phase II (CSNS-II) project, several multi-channel beam diagnostic detectors are installed, including a Ionization Profile Monitor (IPM) for measuring the injection beam profile and a Multi-Wire Profile Monitor for measuring the target beam profile. In the China Spallation Neutron Source (CSNS), similar multi-channel detectors typically utilize multiple PXIe acquisition cards to construct a PXIe-based signal acquisition system, which suffers from high cost and limited flexibility. This paper presents an alternative signal readout solution using a multi-channel high-speed digitizer to replace the PXIe system. The digitizer incorporates built-in front-end amplification functionality, eliminating the need for separate analog electronics for signal amplification. With a maximum sampling rate of 125 MS/s, it fully meets the sampling requirements for the beam pulse width in the CSNS-II Rapid Cycling Synchrotron (RCS), which ranges from 500 ns to 80 ns. Moreover, the multi-channel signal acquisition system implemented with this digitizer offers high integration and reduced cost compared to the PXIe system, making it an ideal choice for beam diagnostics systems.
Paper: MOP6623
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6623
About: Received: 13 May 2026 — Revised: 16 May 2026 — Accepted: 17 May 2026 — Issue date: 22 May 2026
MOP6660
Design and integration of motion control for the Iut24 in-vacuum undulator at TPS
556
The In-Vacuum Tapered Undulator (IUT24) was developed for the Phase-III beamline project at the Taiwan Photon Source (TPS). To counteract strong, non-linear magnetic attraction forces while maintaining precise synchronization between magnet arrays, a robust motion control architecture was implemented. This system integrates an EPICS-based supervisory layer with EtherCAT field I/O and BiSS-C absolute linear encoders (50 nm resolution) in a closed-loop pulse command configuration. Experimental results demonstrate that during dynamic gap transitions, the tracking error is strictly maintained within ± 2.5 𝜇m, and inter-axial synchronization remains within 0.5 𝜇m. Furthermore, long-term position stability was measured at ±150 nm over 200 minutes. This paper details the hardware integration, advanced motion control strategies, and comprehensive performance evaluations that confirm the system’s readiness for high-precision beamline operations.
Paper: MOP6660
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6660
About: Received: 15 Apr 2026 — Revised: 17 May 2026 — Accepted: 21 May 2026 — Issue date: 22 May 2026
MOP6662
Development of an MTCA.4-based Digital Low-level RF Control Solution for the TLS Linac System
560
The Linac of Taiwan Light Source (TLS) has operated for over thirty years, necessitating modernization to ensure sustainability operation. A new digital low-level RF (DLLRF) control system has been developed to replace aging components and address the situation of having only a single backup unit. The MTCA.4 platform was adopted for its scalability and high-performance throughput. The system integrates the DACs module for arbitrary waveform generation with external triggering, and a direct-sampling down-converter with the ADCs module for waveform acquisition and advanced real-time diagnostics. The DLLRF interface has been fully integrated into the EPICS framework for seamless compatibility with existing controls. The new system supports I/Q waveform downloads with online amplitude and phase adjustments, and it provides waveform digitization capabilities for monitoring RF signals associated with the klystron modulator. Dedicated graphical applications have been designed and integrated into the current operator interfaces. The MTCA.4-based DLLRF system has been successfully deployed and validated during routine operations. This paper presents the development, implementation, and operational results of the upgraded control system.
Paper: MOP6662
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6662
About: Received: 15 Apr 2026 — Revised: 14 May 2026 — Issue date: 22 May 2026
MOP6665
Implementation and performance evaluation of a high-resolution bunch-by-bunch phase detection system with geometric calibration
567
A high-resolution, real-time bunch-by-bunch phase detection system has been developed and deployed at the Taiwan Photon Source (TPS) to monitor and analyze synchronous phase behavior. The system is integrated with the control system to implement the remote phase adjustment function. The detector architecture utilizes an analog I/Q demodulation scheme operating at the 1.5 GHz third harmonic of the RF frequency to achieve precise phase extraction. Limited by hardware non-idealities, DC offsets and quadrature phase imbalances distort the I/Q signal trajectory into an elliptical profile, leading to periodic measurement errors. To address these issues, a digital calibration strategy based on ellipse-fitting is implemented to eliminate offsets and quadrature errors within the I/Q channels. After calibration, the phase error of this system at 1.5 GHz is within 1.5°, therefore, when used to measure a 500 MHz signal, the corresponding phase error is within ±0.5°. The extracted phase data is integrated into the accelerator control system with a 3 Hz update rate, enabling real-time visualization of transient beam loading effects. Furthermore, the system’s capability to record 700 turns of bunch motion for phase variation analysis.
Paper: MOP6665
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6665
About: Received: 12 May 2026 — Revised: 20 May 2026 — Issue date: 22 May 2026
MOP6669
Distributed control of large-scale magnet power supplies in the HALF
575
The fourth-generation synchrotron radiation source, with its ultra-high brightness and nanometer-level spatial resolution, has become a core facility supporting cutting-edge scientific research. The Hefei Advanced Light Source comprises over 2,000 magnet power supplies, requiring remote online adjustment and synchronized current settings to meet the physical requirements of the electron beam. This paper proposes a distributed control system architecture to address the control requirements of large-scale magnet power supplies. At the hardware level, build server clusters and leverage virtualization technology to deliver highly available system services. At the network level, a star-topology Ethernet network and a synchronized timing network are constructed. At the software level, a customized communication protocol enables remote monitoring of the magnet power supply. Additionally, data security and efficient deployment were also taken into consideration. This distributed control system provides a scalable solution for batch magnet management in fourth-generation light sources.
Paper: MOP6669
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6669
About: Received: 16 Apr 2026 — Revised: 19 May 2026 — Accepted: 21 May 2026 — Issue date: 22 May 2026
MOP6673
A sliding mode control approach for photon beam stability at the Siam Photon Source
582
This paper presents the enhancement of photon beam position stability at the Siam Photon Source (SPS) through a real-time feedback control system based on a Sliding Mode Control (SMC) algorithm. The proposed system employs Photon Beam Position Monitor (pBPM) measurements within a global orbit feedback loop to minimize beam position fluctuations. The SMC-based Fault-Tolerant Control (FTC) algorithm enhances system robustness by effectively compensating for disturbances, and actuator faults, thereby maintaining stable beam conditions under various operational scenarios. Experimental results demonstrate that the integration of SMC significantly reduces photon orbit deviations and improves synchrotron radiation quality. By strengthening reliability and adaptability, the developed control system ensures precise beam positioning, making the SPS more dependable for scientific and industrial applications that demand high beam stability.
Paper: MOP6673
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6673
About: Received: 06 May 2026 — Revised: 15 May 2026 — Accepted: 17 May 2026 — Issue date: 22 May 2026
MOP6677
Preliminary Design of Beam Feedback Systems for the Shenzhen Superconducting Soft X-ray Free Electron Laser
586
The Shenzhen Superconducting Soft X-ray Free Electron Laser (S3FEL) requires a high-quality electron beam with stable energy, bunch length, and arrival time to ensure efficient lasing. To maintain stringent beam quality, a comprehensive beam feedback system has been preliminarily designed, incorporating five dedicated feedback loops: 1.Gun Feedback: Monitors bunch charge and arrival time after the electron gun, controlling the input laser power and delay to stabilize charge and timing. 2.Laser Heater Feedback: Measures beam energy at the laser heater and adjusts the RF amplitude of small module CM00 and large module CM01 accordingly. 3.Bunch Compressor 1 (BC1) Feedback: Monitors beam energy, energy spread, and bunch length in BC1, regulating RF amplitude and phase of large modules CM02, CM03 and harmonic cavities CMH01, CMH02. 4.Bunch Compressor 2 (BC2) Feedback: Similarly monitors beam parameters in BC2 and controls RF amplitude and phase of large modules CM04–CM09. 5.Linac End Feedback: Measures final beam energy and adjusts RF amplitude and phase of large modules CM10–CM20 to ensure energy stability before transport to the undulator. This integrated feedback design aims to suppress slow drifts, enhance beam stability, and provide the reliable beam quality required for high-performance soft X-ray FEL operation at S3FEL.
Paper: MOP6677
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6677
About: Received: 13 May 2026 — Revised: 15 May 2026 — Accepted: 16 May 2026 — Issue date: 22 May 2026
MOP6682
R&D of the Bunch-by-Bunch Feedback Processor Prototype for HALF
593
The Hefei Advanced Light Facility (HALF) is designed to generate and operate with a beam current of up to 350 mA while maintaining the beam emittance at the diffraction-limited level. The bunch-by-bunch feedback system serves as a critical tool for suppressing beam instabilities, requiring feedback control targeting the position oscillations of each bunch. To meet this demand, the engineering team has independently developed a bunch-by-bunch feedback system, fabricated a prototype, and conducted relevant tests. Through high-precision phase alignment, the analog front-end conditions the original signals into high-precision and wide-dynamic-range sum-and-difference signals. Utilizing the phase-splitting and time-delaying method, the processor can measure the high-precision three-dimensional (3D) position of each bunch and implement feedback control accordingly. This paper presents the design of the system as well as the details of the prototype development and testing.
Paper: MOP6682
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6682
About: Received: 11 May 2026 — Revised: 15 May 2026 — Accepted: 18 May 2026 — Issue date: 22 May 2026
MOP6685
Integrating FPGA into epics for on-the-fly scan control at the TPS 35A beamline
601
The growing demand for high-throughput XAS measurements at next-generation synchrotron light sources makes On-the-Fly Scan indispensable. Original software-based implementations improved efficiency but were limited by slow PC communication (~8 Hz) and soft-trigger jitter (<10 ms), restricting precise synchronization for multi-axis, non-linear trajectories and long-range energy scans. This work introduces a hardware-level fly-scan architecture that deeply integrates a Field-Programmable Gate Array (FPGA) into the EPICS control system at the TPS 35A beamline. Acting as a hardware acceleration core, the FPGA eliminates OS-induced latency and leverages high-speed parallel processing to achieve deterministic control. The system synchronously encapsulates ADC detector data, precise time tags, and high-speed position encoder feedback with nanosecond-level precision, enabling real-time trajectory compensation. This capability supports nano- to micro-second–scale measurements, opening new opportunities for time-resolved XAS. By replacing software delays with hardwired logic, this EPICS-FPGA paradigm delivers a standardized, stable, and highly efficient XAS measurement platform, critical for photon dose-sensitive samples. It fully realizes the hardware upgrade envisioned by previous software-based solutions, setting a new benchmark for high-performance beamline control.
Paper: MOP6685
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6685
About: Received: 13 May 2026 — Revised: 15 May 2026 — Accepted: 16 May 2026 — Issue date: 22 May 2026
MOP6697
Neural network-based amplitude feedforward control algorithm for LLRF systems
617
In free-electron laser facilities, the amplitude-phase stability of the microwave pulses driving the electron beam is a key factor determining beam energy spread. Aiming at the long bunch train operation mode, this paper proposes a neural network-based amplitude feedforward control for low-level radio frequency (LLRF) systems to suppress intra-pulse amplitude fluctuations. The algorithm has been validated at the output of a solid-state amplifier (SSA): under four randomly selected vector modulator (VM) output configurations, the average intra-pulse amplitude flatness (RMS) was reduced from 1.208% to 0.398%, and the average peak-to-peak variation was reduced from 4.683% to 1.353%, demonstrating a significant compensation effect.
Paper: MOP6697
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6697
About: Received: 15 Apr 2026 — Revised: 18 May 2026 — Accepted: 20 May 2026 — Issue date: 22 May 2026
MOP6698
Design and testing of a universal embedded feedback controller for RF cavities
620
The design of low-level feedback (LLRF) controllers used to stabilize the amplitude and phase of the field inside the RF cavities is typically customized, depending on the frequency and mode of operation. IUAC, New Delhi, India, operates accelerators with RF structures in the range of 12.125-97 MHz, in both normal and superconducting modes. Currently, all the LLRF controllers that have been operational for many years are structure-specific and designed in the analog electronics domain. Component ageing, obsolescence, and limited availability have made it challenging to maintain them due to frequent failures. To overcome this, a universal digital controller has been developed whose design is based on the philosophy of using the same hardware for all the RF structures at IUAC. It is a compact, reconfigurable, and standalone device featuring a microcontroller programmed fractional Phase Locked Loop multiplier for generating various LO signals and system clocks, a wideband analog front end for up/down conversion and signal conditioning, and a System-on-Chip FPGA-based digital board with fast ADCs and DACs, all controlled using an EPICS IOC. The controller is designed as a Sawtooth Waveform Generator for the multi-harmonic buncher, a generator-driven, and a self-excited loop-based LLRF for various RF cavities at IUAC. It operates within acceptable limits of 1% RMS variation in amplitude & a ±1-degree variation in phase. Design details & test results will be discussed in the paper.
Paper: MOP6698
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6698
About: Received: 15 Apr 2026 — Revised: 16 May 2026 — Issue date: 22 May 2026
MOP6700
Comprehensive integration and innovation on the 1.5 GHz SRF harmonic cavity control system at NSRRC
624
This paper presents a self-developed, comprehensive electronic control system for the Superconducting Radio-Frequency passive Harmonic Cavity (SRF HC) at the Taiwan Photon Source (TPS) in Hsinchu, Taiwan. The system integrates the Break Out Box (BOB) interfaces for the cavity, Valve Box (VB), cooling water signals, and interlock systems. Additionally, it includes an intuitive correction module and updates for the discontinued or unmaintainable dial gauge module, ensuring that the system operates safely and transparently with clear status display.
Paper: MOP6700
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6700
About: Received: 08 May 2026 — Revised: 16 May 2026 — Accepted: 17 May 2026 — Issue date: 22 May 2026
MOP6703
Machine-learning surrogate modeling of the RAON LEBT beamline
631
We present a machine-learning surrogate model for the RAON LEBT that enables fast prediction of beam centroids at multiple diagnostics. A dataset of TRACK simulations spanning relevant steering-magnet and electrostatic-quadrupole settings is used to train fully connected neural networks. The surrogate model reproduces the underlying beam dynamics with high accuracy while providing orders-of-magnitude faster evaluation. This approach supports rapid orbit studies, optimization, and data-driven beam control in the RAON front-end transport system.
Paper: MOP6703
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP6703
About: Received: 11 May 2026 — Revised: 21 May 2026 — Issue date: 22 May 2026
MOP7001
Upgrade of the arcing suppression system for the waveguides in the European XFEL
634
When planning the European XFEL, the decision was made to avoid using SF6 in the waveguide systems. Instead, air was used at slight to high overpressure. When slight overpressure is used, the air is also in motion. The air flow travels from the RF source towards the cavities and is released again before the coupler. This ensures that, in our non-gas-tight waveguide system, the air quality in the waveguides corresponds to the air quality supplied by the compressor. Particles and ionised air that could promote arcing are blown out. Originally, the air pressure was generated by local compressors and the air used came from the ambient atmosphere. Now, the accelerator’s central compressed air system is utilised. Locally, only the newly developed controls for air pressure and flow remain. The advantage of the central compressed air supply lies in the significantly better air quality and greater operational reliability.
Paper: MOP7001
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP7001
About: Received: 07 May 2026 — Revised: 17 May 2026 — Accepted: 17 May 2026 — Issue date: 22 May 2026
MOP7011
SSPA efficiency improvement studies at ALBA in the framework of the RF2.0 project
655
ALBA is a 3rd generation synchrotron light source and is member of the RF2.0 project, which aims to reduce the carbon footprint of this kind of large research facilities by improving its efficiency, reliability and operational sustainability. In this contribution, we present the work done together with our partner COMMTIA, that has developed the Adaptive Power and Digital Control (APDC) for a 5 kW 1.5 GHz SSPA amplifier, which enables a real-time efficiency optimization by changing dynamically the drain voltage of the transistors while delivering RF power. This is done in two different ways: either the SSPA sets the desired voltage as function of the output power or the Digital Low Level RF system sets the voltage to the SSPA by means of a digital signal. This maximizes the efficiency at each point of operation, ensuring stable performance under the varying load and thermal environments common on accelerator facilities. The laboratory measurements indicate substantial improvements in efficiency, that comes with the cost of the SSPA linearity gain reduction. These developments show how flexible solid-state RF systems can satisfy demanding high-performance requirements while lowering the energy consumption and carbon footprint of accelerator infrastructures.
Paper: MOP7011
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP7011
About: Received: 13 May 2026 — Revised: 17 May 2026 — Accepted: 17 May 2026 — Issue date: 22 May 2026
MOP7049
1.6 MW, 144 MHz solid state power amplifier for ELSA electron linac
739
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 system. The second part of the renovation concerns 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 Ampegon company. One of the challenges was to design a compact amplifier to keep the same footprint. This paper will present the amplifier, the tests and the commissionning.
Paper: MOP7049
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP7049
About: Received: 11 May 2026 — Revised: 15 May 2026 — Issue date: 22 May 2026
MOP7052
Operational experience on a commercial solid state power amplifier with integrated LLRF unit
746
In this contribution we report on the operational experience gained with a commercial off-the-shelf solid-state RF power amplifier equipped with an embedded low-level RF (LLRF) control system, in use for the sub-harmonic buncher cavity of the HB2TF project at INFN LASA. We summarize the motivations behind adopting a turnkey solution, highlighting expected benefits in terms of reliability, maintainability, and integration effort. The talk presents the main results of our testing campaign, including performance stability, response under varying operating conditions, and preliminary assessments of control accuracy. Finally, we provide notes on the synchronization strategy implemented to interface the RF control system with the laser-driven photo-cathode used as beam source.
Paper: MOP7052
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP7052
About: Received: 10 May 2026 — Revised: 18 May 2026 — Issue date: 22 May 2026
MOP7063
The New Calibration System for Magnetic Field Probes at the LNF-INFN Magnetic Measurement Laboratory
775
Accurate calibration of NMR probes is essential for high-quality magnetic-field measurements. Within the PNRR IRIS project, the Magnetic Measurement Facility (MMF) at LNF-INFN has implemented a new dedicated calibration system designed and manufactured by CAYLAR. The setup includes a 2.23 T dipole magnet with a 35 mm gap, a 1ppm four-quadrant power supply for low-field operation, and three NMR probes with associated electronics, covering the 200 G to 2.2 T range. The probes are mounted on a dedicated holder positioned in a highly uniform field region, ensuring that all sensors experience the same magnetic environment. Achieving excellent homogeneity over a large volume and wide field range was a key challenge; this was addressed through a genetic-algorithm-optimized magnet design complemented by active shimming coils. This contribution presents the system’s design, construction, and factory acceptance tests, along with the first calibration results obtained at MMF. Future improvements include thermostating the probe holder, potentially using cryogenic liquids, to extend the temperature range for calibrations, an important capability for probes used in superconducting magnets.
Paper: MOP7063
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP7063
About: Received: 13 May 2026 — Revised: 15 May 2026 — Accepted: 17 May 2026 — Issue date: 22 May 2026
MOP7087
Large-scale helium refrigeration cryogenic systems costing for superconducting particle accelerators such as the FCC-ee
828
Large-scale helium refrigeration cryogenic systems are a key element, essential to the safe and reliable operation of particle accelerators using superconducting devices such as radio-frequency cavities or magnets. The long-term success of the LHC operation with an outstanding physics production to date paves the way towards the High-Luminosity LHC (HL-LHC) upgrade to be operated until the early 2040s, after which it could be followed by the Future Circular Collider (FCC). Such large-scale projects, requiring a significant amount of cryogenic cooling capacity to be installed, pose the question of the cost estimation methodology to be employed, as the cryogenic system represents a non-negligible fraction of the total capital, operation & maintenance cost of the facility. Capitalizing on the experience of the LHC project, then on its recent HL-LHC upgrade, the existing CERN methodology was updated with the latest available industrial indexation, thus allowing the cost of the FCC cryogenic system to be assessed. This paper reports on the approach used to estimate the cost of the FCC cryogenics, refining the method adopted at the time of the LHC project. It considers the evolution of material and labour costs over the past two decades, studies the updated economics of 4.5 K and 1.8 K helium refrigeration, and presents the strong impact of the cryogenic distribution system. It also identifies and proposes ways for improving the capital, operation & maintenance expenditure.
Paper: MOP7087
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP7087
About: Received: 06 May 2026 — Revised: 17 May 2026 — Accepted: 19 May 2026 — Issue date: 22 May 2026
MOP7098
The beam stops for the ESS superconducting linac
851
For the ESS superconducting linac in Sweden, four compact beam stops were designed instead of bulky beam dumps. The beam stops dump protons either up to 100 MeV or 250 MeV; the most demanding beam modes have an average beam power of 700 or 1100 W, respectively. The beam stops are water-cooled and moved by pneumatic actuators. The beam stops were designed at the ESS in Sweden and manufactured by Proactive R&D in Spain. The assembly, acceptance tests and metrology measurements were performed in ISO-5 cleanrooms, before the installations in the particle-free environment next to superconducting cavities of the ESS linac. This contribution summarizes the assembly, testing and operational experience.
Paper: MOP7098
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP7098
About: Received: 11 May 2026 — Revised: 17 May 2026 — Accepted: 17 May 2026 — Issue date: 22 May 2026
MOP7102
Functionalised a-C coatings to reduce SEY and control surface resistance for the HL-LHC injection kicker beam-pipe ceramic supports
861
Functionalized amorphous carbon (a-C) coatings are being developed to reduce the secondary electron emission yield (SEY) and to control the surface resistance of ceramic supports for the new generation of HL-LHC injection kicker magnets. Pressure spikes observed during high-voltage pulsing of the new injection kicker magnets are attributed to flashovers caused by high electron emission and insufficient draining of surface charge on the alumina supports of the beam-pipe. To address this issue, the alumina supports for the next generation of injection kicker magnets are coated with an a-C film, providing suitable surface resistivity to prevent charge accumulation whilst preserving the insulating function of the supports, together with a low SEY. This contribution reports on the R&D programme aimed at tuning the resistivity of the a-C films through hydrogen doping while maintaining acceptable SEY performance. Results from the production of a series of 25 coated supports are presented, along with comple-mentary studies carried out to optimise the coating pro-cess for future large-scale production. The potential of these resistive a-C films as alternatives to Ti and TiN coatings for insulating components is also discussed.
Paper: MOP7102
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP7102
About: Received: 13 May 2026 — Revised: 15 May 2026 — Accepted: 16 May 2026 — Issue date: 22 May 2026
MOP7109
Quality assurance for the HL-LHC beam screen production
885
The HL-LHC project is currently in the fabrication and assembly phase for numerous components and systems, in particular the new beam-screen assemblies to be installed inside the upgraded final-focusing superconducting magnets operating at 1.9 K. These complex beam screens integrate tungsten absorbers and exist in two variants: the Q1 and Q2 types, with absorber thicknesses of 16 mm and 6 mm, respectively. In total, 24 assemblies will be installed. Their successful implementation requires complex design work, non-standard and demanding manufacturing processes, and stringent quality assurance. Fabrication has proven to be very challenging in terms of welding and assembly and requires close follow-up and dedicated qualification processes throughout the manufacturing phase. To maintain a high standard of manufacturing, a Quality Management approach derived from industrial standards and based on ISO 9001 principles, has been implemented. This paper presents how the quality-management framework is deployed throughout the project phases and how it ensures traceability, smooth process execution, and compliance with the required workflows and technical specifications.
Paper: MOP7109
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP7109
About: Received: 13 May 2026 — Revised: 20 May 2026 — Issue date: 22 May 2026
MOP7123
A Hall-probe calibration setup in the temperature range from 300 K to 4 K at European XFEL
912
Precise magnetic-field measurements are essential for the characterization of both superconducting (SC) and permanent-magnet (PM) undulators. Since the accurate characterization of these devices relies directly on precisely calibrated Hall probes, a dedicated Hall-probe calibration setup for magnetic fields from -2T to +2T has been developed, produced, and commissioned at European XFEL, capable of operating over a broad temperature range from 300 K down to 4 K. This contribution presents the setup and first results.
Paper: MOP7123
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP7123
About: Received: 18 May 2026 — Revised: 19 May 2026 — Accepted: 21 May 2026 — Issue date: 22 May 2026
MOP7142
The CYREN project: Refurbishment of the GANIL cyclotrons facility
971
For over 40 years, the GANIL facility has been supplying stable beams (carbon to uranium, 60 keV/A to 95 MeV/A) and low- and high-energy radioactive ion beams for fundamental, applied and industrial research from a set of 5 cyclotrons. Since 2010, due to the SPIRAL2 construction and compliance projects associated with the French safety regulations, the cyclotrons maintenance and refurbishment were reduced to a bare minimum, and as a consequence the failure rate increased over the years. Present scientific and industrial demand for GANIL cyclotrons beams, and projection for future demands over the years to come, request GANIL to guarantee the operation over the next 20 years or more. Therefore an ambitious renovation program, the CYREN (Cyclotrons Renovation) project, was launched in 2024. This article covers the progress of this project, detailing the challenges, partly due to the diversity of the different installations, the uniqueness of the equipment and the sometimes aging, implemented technologies. The project covers a broad variety of equipment from the 5 cyclotrons, beam lines, the associated experimental caves, building infrastructures, technical utilities and the safety, security and radiation protection systems.
Paper: MOP7142
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP7142
About: Received: 13 May 2026 — Revised: 19 May 2026 — Accepted: 20 May 2026 — Issue date: 22 May 2026
MOP7143
Updates on the sustainability improvements of the Karlsruhe Research Accelerator
974
The thermal well system to support the cooling plant of the accelerator test facility Karlsruhe Research Accelerator (KARA) at the Karlsruhe Institute of Technology (KIT) is in test operation after about one year of commissioning. To avoid any impact on the environment, follow the governmental regulations, and document different aspects and operation statistics, KIT developed a special robust and reliable data handling pipeline. We describe the implementation of the data archiving strategy, as well as the experiences gained and statistics on e.g. power reduction from the first year of commissioning of the thermal wells. Furthermore, our plans for improvement and extension of KARA's efforts towards sustainable operation are presented.
Paper: MOP7143
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP7143
About: Received: 12 May 2026 — Revised: 16 May 2026 — Accepted: 17 May 2026 — Issue date: 22 May 2026
MOP7151
Challenges in the Development of the SIS100 Electrostatic Extraction System
998
The "Facility for Antiproton and Ion Research" (FAIR) is a new international accelerator complex, which is currently built in Darmstadt, Germany. Part of this complex is the SIS100 heavy ion synchrotron with a circumference of ~1086 m. One of the required extraction systems is the electrostatic septum. This septum was built by Danfysik. It is operating with voltages up to 180 kV. The requirements on the vacuum quality (low 10-11mbar region) combined with voluminous chambers (in total ~6m long), the reproducibility and precision of the applied voltage as well the mechanical stability and exact positioning even after bakeout cycles up to 300 °C have been the biggest challenges on this project. Specifications on rise and fall times for the high voltage implies the need of a bleeder resistor, used for improved voltage accuracy, too. During this project numerous problems had to been solved to end up with a stable system. The results of the tests and lessons learned will be presented.
Paper: MOP7151
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP7151
About: Received: 12 May 2026 — Revised: 14 May 2026 — Accepted: 19 May 2026 — Issue date: 22 May 2026
MOP7152
Development of a guanella-type 4:1 impedance transformer for the future SIS100 broadband cavity systems
1001
The SIS100 heavy-ion synchrotron under construction at GSI/FAIR will contain a total of 4 broadband cavities for barrier bucket and longitudinal feedback operation. These need to generate non-harmonic gap voltages with relevant spectral components in a range from 100 kHz to 15 MHz. Previous analyses showed that the input capacitance of the tetrode amplifier limits the cavity’s upper cutoff frequency. To counteract this effect, the load impedance at the input of the tetrode amplifier shall be reduced from 50 ohms to 12.5 ohms at the expense of more driver amplifier power. In this case, achieving an impedance matching to the driver amplifier necessitates the inclusion of a transformer generating a broadband 4:1 impedance transformation over the entire relevant frequency range. A Guanella-type 4:1 ferrite transmission line transformer meeting these requirements was developed, built, and verified by measurement.
Paper: MOP7152
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP7152
About: Received: 15 Apr 2026 — Revised: 03 May 2026 — Accepted: 22 May 2026 — Issue date: 22 May 2026
MOP7158
Evaluation of low-cost, multimodal-sensor, data acquisition systems for ad-hoc applications in particle accelerators
1017
With more than 30km of beam lines and over 10,000 devices, CERN's particle accelerators are rich sources of data, providing real opportunities for developing new equipment monitoring and automation tools using data analysis and machine learning. The ready availability of low-cost computers and microcontrollers, such as Raspberry Pi and ESP32 devices, could enable a flexible data acquisition system for short-term applications that do not require, or cannot justify, the development and installation of permanent acquisition infrastructure. This paper presents the initial work from a pilot project to develop such a system, and assesses its use for several applications, including speculative investigations of environmental conditions, such as temperature and high-energy hadron flux, as well as assessing the feasibility of detecting arc faults in power converters, and gathering datasets for training machine learning models. Key considerations for the implementation of this system are also discussed, including concerns around network security, data quality, data availability, hardware configurations, deployment conditions, and avoiding control system dependency, with initial recommendations given for each.
Paper: MOP7158
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP7158
About: Received: 08 May 2026 — Revised: 16 May 2026 — Accepted: 17 May 2026 — Issue date: 22 May 2026
MOP7159
ETHERNET-ENABLED DATA ACQUISITION AND SUPERVISION SYSTEMS FOR THE HL-LHC QUENCH PROTECTION SYSTEM
1021
Ethernet-enabled Data Acquisition and Supervision (EDAQ) systems have become the standard platform for commissioning, controlling, and supervising the next generation of Quench Protection Systems (QPS) at CERN. EDAQ-equipped QPS devices have been installed in recent upgrades to magnet test facilities, most notably in the IT-String test facility. This contribution summarizes the operational experience gained during these installations and highlights the key advancements that have enabled the EDAQ ecosystem to mature into a production-ready solution. Notable developments include a configuration validation system, improved error-recovery strategies, over-the-air (OTA) firmware updates, and seamless integration with the full range of HL-LHC QPS equipment. The results of a comprehensive set of performance tests are presented and discussed, confirming that the EDAQ system is ready for deployment as part of the High Luminosity LHC upgrade, for which the installation is to start in the coming years.
Paper: MOP7159
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP7159
About: Received: 14 May 2026 — Revised: 17 May 2026 — Accepted: 17 May 2026 — Issue date: 22 May 2026
MOP7168
Hight Voltage Electric dipole conditioning for the Super spectrometer separator at GANIL/SPIRAL2
1048
The “Super Separator Spectrometer” project S3 is under technical commissioning at the GANIL facility (Caen-France). It is a new research installation designed for fundamental physics experiments with high intensity radioactive heavy ions beams produced by the SPIRAL2 linear accelerator. This spectrometer will open new horizons for nuclear physics. The S3 spectrometer is made of 77 superconducting magnets, 12 room temperature magnets and one high-electric field dipole. This electric dipole combined with a magnetic dipole will allows a very precise energy/mass selection of ions with extremely small effective sections. This paper presents the electric dipole technology and its initial high voltage conditioning carried out on-site in 2025.
Paper: MOP7168
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP7168
About: Received: 12 May 2026 — Revised: 16 May 2026 — Issue date: 22 May 2026
MOP7175
Large scale production of amorphous carbon coatings for the new beam screens of the HL-LHC project
1071
The new beam screens for the High Luminosity LHC (HL-LHC) will be coated with a low Secondary Electron Yield (SEY) amorphous carbon (a-C) thin film to suppress electron multipacting and reduce heat loads to the cryogenic system. The production will cover 40 beam screens for the new superconducting magnets of the inner triplets in LHC interaction regions 1 (ATLAS) and 5 (CMS), as well as 24 beam screens for the drift line of the cryomodules housing the CRAB cavities. This contribution presents the implementation of a large-scale coating facility dedicated to the deposition of a-C films on the various HL-LHC beam screens, adaptable to different geometries and lengths up to 14 meters. The rationale behind the chosen coating technology and process parameters is discussed, with emphasis on adhesion optimization, SEY minimization, and production throughput to meet the HL-LHC schedule. We report on the current status of the production campaign, including quality assurance statistics, and highlight the main challenges encountered together with the solutions adopted.
Paper: MOP7175
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP7175
About: Received: 12 May 2026 — Revised: 15 May 2026 — Accepted: 16 May 2026 — Issue date: 22 May 2026
MOP7180
Cooling-Tower technologies for the IFMIF-DONES heat rejection system: technical and environmental considerations
1089
The International Fusion Materials Irradiation Facility-DONES (IFMIF-DONES) is a scientific infrastructure intended to test and qualify materials for fusion reactors by exposing them to intense neutron fluxes. Several auxiliary systems will ensure its continuous operation, among which the Heat Rejection System (HRS) is designed to remove and discharge to the environment the heat mainly generated by the Accelerator's primary cooling loops and the Test Cell. While open evaporative cooling towers are widely used for industrial heat rejection, alternative technologies may be more suitable depending on site-specific conditions and project priorities. Environmental factors—particularly local weather patterns and their expected evolution under climate change—play a decisive role in overall system performance. Their proper assessment is therefore essential for selecting the most appropriate cooling-tower technology. This work presents a comparative evaluation of candidate heat-rejection solutions to identify the technology that best fits the site conditions, optimises performance over the system's life cycle, and supports the project's commitment to minimising its environmental footprint.
Paper: MOP7180
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP7180
About: Received: 13 May 2026 — Revised: 19 May 2026 — Accepted: 21 May 2026 — Issue date: 22 May 2026
MOP7181
Energy Efficiency in the North Experimental Area at CERN
1092
The North Experimental Area at CERN is a versatile experimental facility that provides proton, hadron, electron, muon, and ion beams to over 2000 users annually for detector R&D and fixed-target experiments. Currently, this facility, which is more than 45 years old, is undergoing a consolidation program to enhance availability and reliability and to prepare for new experiments and test beams in the coming decades. In this context, and within the framework of ISO 50001, energy efficiency was assessed, potential energy-saving opportunities were identified, and various strategies for sustainable operation were evaluated. This contribution summarizes the results and outlines planned measures for future implementation.
Paper: MOP7181
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP7181
About: Received: 13 May 2026 — Revised: 15 May 2026 — Accepted: 21 May 2026 — Issue date: 22 May 2026
MOP7182
Metal Additive Manufacturing for Accelerator Technologies (MAAT project at INFN)
1096
The MAAT (Metal Additive Manufacturing for Accel-erator Technologies) project is a three-year INFN re-search programme launched in 2026, aimed at establish-ing Additive Manufacturing (AM) as a validated produc-tion route for high-performance accelerator components. MAAT brings together three INFN units: Legnaro (LNL), Padova (PD), and Milano LASA, combining complemen-tary expertise in superconducting RF, materials science, and advanced manufacturing. This paper reports on the activities and preliminary results during the first year of the project, covering: 1. the Design for Additive Manufacturing (DfAM) of 6 GHz cavities produced by Laser Powder Bed Fusion (LPBF). 2. the preliminary tests of the Wire Laser Additive Manufacturing (WLAM) combined with CNC ma-chining for the fabrication of a 1.3 GHz RF cavity prototype in CuCrZr.
Paper: MOP7182
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP7182
About: Received: 13 May 2026 — Revised: 20 May 2026 — Issue date: 22 May 2026
MOP7183
Operational Sequencer at the European Spallation Source
1099
The Operational Sequencer is a software framework developed to automate complex and frequently executed high-level procedures that are essential to the operation of accelerator systems at the European Spallation Source (ESS). By transforming manual control room tasks into predefined sequences, the tool enhances process repeatability, reliability, and safety by reducing human error. Designed within the ESS Integrated Control System Software group, the sequencer provides a unified architecture for defining, executing, and monitoring operational tasks. It supports multiple task execution types, scalable system design, and an intuitive graphical interface to facilitate operator oversight. This paper presents the architectural concepts, implementation challenges, and scalability strategies of the Operational Sequencer, as well as lessons learned from its deployment during ESS commissioning. The framework represents a significant step toward efficient and reproducible operations, reducing both operator workload and time-to-beam for scientific experiments.
Paper: MOP7183
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP7183
About: Received: 12 May 2026 — Revised: 19 May 2026 — Issue date: 22 May 2026
MOP7188
Moving tons of fragile crystals with care: the CMS ECAL Enfourneur2 project
1112
The CMS experiment at the CERN Large Hadron Collider features a high-precision electromagnetic calorimeter (ECAL) made of 61,200 lead tungstate crystals in its central (barrel) part. The crystals are both heavy and fragile, requiring extreme care during handling. As part of the HL-LHC upgrade, the ECAL barrel front-end electronics will be replaced, requiring the extraction, refurbishment, and re-insertion of all 36 supermodules (SM), each weighing about 3 tons, within a strict schedule of the technical operations inside the CMS cavern during Long Shutdown 3. A specialized machine, the Enfourneur, will be used for SM extraction. To accelerate operations, a second Enfourneur has been developed, replacing hydraulic actuators with electrical motors and controls. The new system manages three movements: rotation to the insertion angle, forward-backward motion, and controlled SM push-pull. Safety of SMs handling is ensured by numerous sensors and an advanced control system. A touchpad interface provides real-time control of SMs positioning with extreme accuracy, thanks to the implementation of electric motors and related controls, and operational safety, offering to the machine operator predefined movements, fine adjustments, and a continuous monitoring of the forces applied by the machine and ongoing deformations on the most critical metallic carpentry structures. This paper details the Enfourneur 2 design, commissioning and operational performance after an intensive testing campaign carried out at CERN.
Paper: MOP7188
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-MOP7188
About: Received: 13 May 2026 — Revised: 21 May 2026 — Accepted: 22 May 2026 — Issue date: 22 May 2026
TUI4M02
Accelerator complex evolution at Fermilab
1244
The largest hadron accelerator facility in the US is undergoing radical changes and the undertaking of new HEP-driven neutrino research. This talk will discuss the wide-ranging projects and impacts to the accelerator community taking place at FNAL.
Paper: TUI4M02
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUI4M02
About: Received: 12 May 2026 — Revised: 19 May 2026 — Accepted: 20 May 2026 — Issue date: 22 May 2026
TUP2316
Machine Learning based preventive maintenance and autonomous power control for RF cavities in a free-electron laser
1299
This project develops a machine learning–based system to prevent RF cavity trips in the free-electron laser by autonomously controlling the applied RF power. Sudden vacuum and current fluctuations within the cavities can cause reflections that trip the machine, and continuous manual monitoring throughout the conditioning process isn't feasible. To address this and potentially improve the conditioning efficiency, process-variable data was collected and analyzed to identify patterns in cavity behavior across operating power levels. A hybrid model combining clustering methods, linear regression, and a classifiers was designed to categorize current ranges, estimate baseline behavior, and detect anomalies. The resulting control program evaluates the machine state over short intervals, decreases power during unsafe conditions, increases it during prolonged stability, and can automatically reset the RF system after a trip. This approach enables faster and safer conditioning of the RF cavities, reduces operator workload, and provides a pathway toward fully autonomous preventive maintenance.
Paper: TUP2316
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUP2316
About: Received: 01 Apr 2026 — Revised: 17 May 2026 — Accepted: 17 May 2026 — Issue date: 22 May 2026
TUP2343
Design and Integration of ALS-U Storage Ring Modules
1342
The Advanced Light Source Upgrade (ALS-U) is an ongoing project at Berkeley Lab to transform the ALS into a fourth-generation synchrotron light source. To minimize the ALS users facility down time, the ALS-U Storage Ring (SR) is composed of 48 unique, highly integrated modules, each split into approximately 11 subsystems. There are over 3000 unique physical interfaces across the system, with 27 interface pairs internal to the module, as well as externally between modules, facilities and beamlines. This contribution presents how the complex interfaces have been managed using interface control documentation and tailored interface verification methods based on a combination of Computer-Aided Design (CAD) assemblies and dedicated prototypes. These tools were adopted to manage both module-level integration and external interfaces with facility infrastructure and beamlines to mitigate integration risks. To validate the design solutions a physical 1:1 mock-up has been developed alongside the CAD models. The combined CAD-mockup validation approach revealed critical issues not detectable through CAD only, including cables’ installation feasibility problems that would have caused redesign work and significant delays. The physical mockup also enabled more accurate analysis of maintenance access, assembly process and electrical safety. The practical experience from SR modules design in facility/beamlines integration context, methodology evolution during the design process, and recommendations for similar accelerator upgrade projects are also presented.
Paper: TUP2343
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUP2343
About: Received: 09 May 2026 — Revised: 17 May 2026 — Accepted: 17 May 2026 — Issue date: 22 May 2026
TUP2344
Electrical integration of the ALS-U storage ring modules
1345
The ALS-U (Advanced Light Source Upgrade) project is an upgrade to the ALS at the Lawrence Berkeley National Laboratory. The new multibend achromat (Storage Ring) will be installed in 16 months. To meet the tight schedule and space constraints, the 48 modules of magnets (called rafts) are prestaged and aligned in advance. All local electrical wiring is prestaged to reduce the installation time in the tunnel. Electrical work includes cabling for grounding, thermocouples, MPS (Machine Protection System), magnet power and correctors, vacuum, beamline feedback (diagnostics), and AC cables, all arranged to minimize heat buildup. Key challenges include raft transport requirements and managing the overall routing as well as future upgrades in the tightly packed lattice arrangement. This contribution presents the electrical integration on the raft during prestaging. It further outlines the testing activities and the prototype rafts developed to validate and optimize installation procedures. It details the schematics, cable and material management for the 48 rafts, as well as the ALS-U configuration management system and databases used for electrical routing.
Paper: TUP2344
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUP2344
About: Received: 22 Apr 2026 — Revised: 18 May 2026 — Accepted: 19 May 2026 — Issue date: 22 May 2026
TUP2607
Beam based alignment of quadrupoles at HEPS
1375
In modern storage ring light source, large offset of quadrupoles will degrade the beam quality in the ring. Beam based alignment(BBA) methods have been used widely in storage rings, to correct the orbit of the beam to the magnetic center of quadrupoles. The BBA algorithm and commissioning procedure at HEPS is described in this paper
Paper: TUP2607
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUP2607
About: Received: 13 May 2026 — Revised: 16 May 2026 — Accepted: 18 May 2026 — Issue date: 22 May 2026
TUP2626
Dynamic aperture prediction based on machine learning
1406
The dynamic aperture(DA) is one of the most important parameters of nonlinear beam dynamics in storage rings. It describes the transverse phase space region where the motion of a particle can remain stable. In the design and optimization of storage rings, long-term particle tracking is usually required to ensure an sufficient DA. However this process is very time consuming. This study explores the possibility of using machine learning methods for DA prediction. Firstly, several regression models from magnet strengths to resonance driving terms are constructed using different machine learning methods, showing that the use of machine learning can be applied to the nonlinear performance analysis of storage ring lattice. Then predictive regression models from magnet strength to DA are constructed, and the results show that artificial neural network have better prediction accuracy. The method will be further developed for nonlinear analysis and optimization of storage ring.
Paper: TUP2626
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUP2626
About: Received: 15 Apr 2026 — Revised: 19 May 2026 — Accepted: 20 May 2026 — Issue date: 22 May 2026
TUP2666
RF Commissioning Results in the SHINE
1463
SHINE is an 8 GeV continuous-wave (CW) free-electron laser (FEL) facility, mainly composed of an injector, a linear accelerator, an undulator segment, and experimental beamlines. Currently, for the accelerator section, the commissioning of the injector and the L1 segment of the linear accelerator has been completed. The RF structures in these two segments include a VHF electron gun, an L-band buncher, a dual-feed superconducting cavity, an injection eight-cavity module, two standard 1.3 GHz cryo-modules, and two 3.9 GHz cryo-modules. The RF specification of these accelerating structures have all met the design requirements. This paper will introduce the final parameters achieved through the commissioning of these accelerating structures and some problems encountered during the commissioning process.
Paper: TUP2666
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUP2666
About: Received: 10 May 2026 — Revised: 22 May 2026 — Issue date: 22 May 2026
TUP2709
Application of deep learning methods for insertion device effects in the SSRF
1543
A deep-learning-based feedforward scheme has been developed to compensate insertion-device (ID) effects in the Shanghai Synchrotron Radiation Facility (SSRF). Neural networks predict orbit and betatron-coupling perturbations caused by ID gap and phase changes. The orbit model reduces residual closed-orbit distortion (COD) to below 2 um and shortens preparation time by about a factor of 50 compared with conventional feedforward-table measurements. A coupling model trained with turn-by-turn (TBT) beam-position-monitor (BPM) data reaches an R^2 value above 0.95. These results show that deep learning can support fast and reproducible ID compensation during light-source operation.
Paper: TUP2709
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUP2709
About: Received: 08 May 2026 — Revised: 12 May 2026 — Accepted: 16 May 2026 — Issue date: 22 May 2026
TUP7009
Operation of the Kara booster in storage-ring mode for accelerator studies and system development
1689
The Karlsruhe Research Accelerator (KARA) booster synchrotron, normally used to accelerate electrons from 53 MeV to 500 MeV for injection into the KARA storage ring, has recently been successfully operated in a stand-alone storage ring mode. This capability was enabled by the modernization of its magnet power supplies and their integration into an EPICS-based control system. Operating the booster in this mode provides a flexible platform for accelerator physics studies, including the development of energy-ramping procedures, characterization of magnet hysteresis effects, and verification of control strategies under low-energy storage conditions. Initial commissioning demonstrated stable beam storage at several energies up to 500 MeV. The future compact storage ring cSTART, designed for energies of 50-90 MeV, is currently being constructed at KIT. The new power supplies allow preliminary experiments to be conducted across this energy level in the KARA Booster, enabling studies of beam and machine characterizations under realistic conditions. Additionally, the ability to store beam up to 500 MeV supports tests relevant for the KARA storage ring. This mode establishes the booster as a compact and flexible experimental platform prior to deployment in cSTART and the main KARA storage ring. Future work will focus on beam dynamics and diagnostics in the lower energy region with reduced radiation damping, as well as optimization of ramping cycles for stable injector operation.
Paper: TUP7009
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUP7009
About: Received: 13 May 2026 — Revised: 18 May 2026 — Accepted: 21 May 2026 — Issue date: 22 May 2026
TUP7315
Progress on upgrades to CCL resonance control at LANSCE
1735
The resonance control system for the cavity-coupled linear accelerator (CCL) portion of the Los Alamos Neutron Science Center (LANSCE) has been a consistent source of operational downtime. The present system has been used since installation with only minor upgrades, so a system is being developed to replace it with modern components to reduce maintenance and downtime. The present control algorithm maintains water temperature at a set point based on the average RF power, and other parameters that are direct indications of resonance such as the cavity field phase or its ratio to forward power should be implemented to improve issues inherent to the present control system. These relevant data have been collected for several RF modules and analyzed. Additionally, the control of the valve used to maintain water temperature is antiquated, and a commercially available off-the-shelf stepper motor driver is required as other parts are upgraded. A prototype of a new system is discussed.
Paper: TUP7315
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUP7315
About: Received: 12 May 2026 — Revised: 18 May 2026 — Issue date: 22 May 2026
TUP7342
Digital signal component separator for the LANL solid-state power amplifier
1764
Because of aging, and product discontinuity, LANSCE is investigating the replacement of high power RF amplifi-ers. A promising candidate is the GaN solid-state power amplifier (SSPA). The outphasing technique provides high efficiency operation of the SSPA. A key element of the outphasing technique is the signal component separa-tor(SCS), which converts an Amplitude Modulation-Phase Modulation(AM-PM) signal to two PM only sig-nals. In this paper, a design of a digital signal component separator (DSCS) in In-phase/Quadrature(I/Q) coordinate is addressed. In addition, the feedback linearizers are pro-posed to suppress the input disturbances to the SSPA. The DSCS is implemented on the present Field Pro-grammable Gate Array(FPGA) based LANSCE digital low level RF (DLLRF) control system. The performance of the DSCS on the cavity field control system is verified on a low power teststand and the results are reported.
Paper: TUP7342
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUP7342
About: Received: 11 May 2026 — Revised: 18 May 2026 — Accepted: 19 May 2026 — Issue date: 22 May 2026
TUP7346
High-power amplifier considerations for testing the LAMP RFQ and first DTL cavity
1768
As part of the LANSCE Accelerator Modernization Project (LAMP), critical portions of the proposed accelerator will be tested as proof of concept and aid in planning the installation of LAMP at Los Alamos Neutron Science Center. As part of this demonstration, the radio frequency quadrupole (RFQ) and the first drift-tube linac (DTL) cavity will be tested with beam. For this purpose, high-power RF amplifiers are being designed to meet the testing demands. This is a description of the requirements of these amplifiers and how the design is intended to meet them.
Paper: TUP7346
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUP7346
About: Received: 15 May 2026 — Revised: 19 May 2026 — Accepted: 20 May 2026 — Issue date: 22 May 2026
TUP7347
High power GaN amplifier development for coupled-cavity Linac at LANSCE
1771
The Los Alamos Neutron Science Center uses a coupled-cavity linac to accelerate H- ions from 100 to 800 MeV. It is powered by forty-four 1.25 MW 805 MHz klystrons, each capable of 150 kW of average power. A prototype solid-state amplifier that meets these requirements is in development. Commercial silicon LDMOS transistors have reduced power above 600 MHz and are also limited by the maximum drain to source breakdown voltage. We are using high voltage Gallium Nitride (GaN) on Silicon Carbide (SiC) high electron mobility transistors (HEMT) to reduce the number of active devices and the complexity of power combing smaller amplifiers. These wide bandgap semiconductors can operate at high channel temperatures around 200 degC without shortened life. We are testing new devices up 5 kW of peak power at 100 volts. Operating in saturation mode, outphasing modulation is used to maintain high device efficiency to reduce thermal dissipation, compared to conventional class AB linear amplifiers. The power supply requires stored energy with a capacitor bank. Power combining uses a combination of 2-way Gysel, 40-way radial and magic tee combiners in waveguide.
Paper: TUP7347
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUP7347
About: Received: 12 May 2026 — Revised: 18 May 2026 — Accepted: 21 May 2026 — Issue date: 22 May 2026
TUP7356
ARIEL radioactive gas management system
1775
The ARIEL facility expands TRIUMF’s isotope production by adding two new target stations operating in parallel with the existing infrastructure, enabling high-intensity Radioactive Ion Beam (RIB) production. At the core of this facility, a complex vacuum system is designed to maintain the conditions required for RIB production while safely managing radioactive gases generated during beam-material interactions. The activated gases from the target and RIB modules are continuously evacuated and transferred via a radioactive gas management system to storage tanks for controlled decay. The radioactive gas management system is designed to support parallel and independent target station operation, prevent cross-contamination between exhaust streams, enable future scalability, and provide fault tolerance to ensure uninterrupted operation in the event of equipment failure. This system incorporates controlled gas recirculation and sampling capabilities to ensure the collection of a uniform sample for radiological assessment prior to release to the nuclear ventilation system. In addition, this system is operated and controlled remotely, enabling remote control of devices, data archiving, and implementation of interlocks for machine protection. Overall, this system offers a robust solution for radioactive gas management in modern accelerator facilities. This work presents the key design features and operational principles of the ARIEL radioactive gas management system.
Paper: TUP7356
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUP7356
About: Received: 19 May 2026 — Revised: 20 May 2026 — Accepted: 21 May 2026 — Issue date: 22 May 2026
TUP7360
A novel magnetic measurement system for cryogenic permanent magnet undulator
1781
A standardized magnetic measurement system exists for evaluating the field characteristics of conventional insertion devices, including in-vacuum undulators designed for NSLS-II, which employ a rectangular measurement window. A In-Vacuum Magnetic Measurement System (IVMMS) valid for 1.5 m long CPMU was developed during the NSLS-II project. However, in the case of cryogenic permanent magnet undulators (CPMUs), each facility implements its own design, and no commercially available measurement apparatus currently exists. At NSLS-II, we intend to retain a side rectangular window for room-temperature characterization. Consequently, a completely new in-vacuum Hall probe system good for longer devices than 1.5 m has been developed to interface with this window. This paper presents a preliminary design of the in-vacuum Hall probe measurement bench, designed to characterize a 3 m-long CPMU planned for the NEXT-III (NSLS-II Experimental Tools III) project beamline.
Paper: TUP7360
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUP7360
About: Received: 05 May 2026 — Revised: 07 May 2026 — Accepted: 16 May 2026 — Issue date: 22 May 2026
TUP7364
Building a MOPA laser for H- beam shaping
1784
We present the design and initial amplification stages of a seeded Master Oscillator Power Amplifier (MOPA) laser for H- beam shaping applications. Customizable modulation of the input (seed) laser pulse shape will be shown to optimize the amplified laser pulse shape output at the nanosecond level, allowing for high speed ‘notching’ or ‘trimming’ of photo-ionized H- bunch shapes. By matching the laser pulse train shape to the inverse of the desired H- bunch shape, the design of our laser system will be theoretically applied to the selective longitudinal neutralization of low energy (1 MeV) H- beams. Theoretically needed pulse energies for high percentage photo-ionizations above 99.9% will be presented and challenges for reaching the required laser pulse energies and repetition rates will be discussed. Finally, we will examine the potential for using these custom laser pulse trains to trim residual tails the H- beam through complex laser pulse shape and multiple laser – bunch interactions in a specially designed high reflectively laser cavity, reducing the total power required to reach high neutralization efficiency.
Paper: TUP7364
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUP7364
About: Received: 13 May 2026 — Revised: 21 May 2026 — Accepted: 21 May 2026 — Issue date: 22 May 2026
TUP7370
Status update of permanent magnet radiation resiliency studies at CEBAF
1787
The proposed energy upgrade of the Continuous Electron Beam Accelerator Facility (CEBAF) incorporates Fixed-Field Alternating-gradient (FFA) arcs utilizing permanent magnet technology. Given the radiation environment within the CEBAF tunnel enclosure, validating the long-term magnetic stability of these materials is a critical step for the project's technical feasibility. This contribution presents an overview of the ongoing permanent magnet radiation resiliency program at Jefferson Lab. We briefly review the experimental methodology used to monitor demagnetization in situ and summarize the operational experience from the initial data-taking campaign. Furthermore, we discuss the upgrades implemented for the second exposure campaign, currently underway, which aims to refine dose correlation and reduce systematic uncertainties. We report on the general status of the program and the roadmap for certifying permanent magnet optics for the proposed upgrade energies.
Paper: TUP7370
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUP7370
About: Received: 01 May 2026 — Revised: 17 May 2026 — Accepted: 17 May 2026 — Issue date: 22 May 2026
TUP7625
Application of magnetic-alloy-loaded cavities beyond 10MHz
1830
Magnetic-Alloy-loaded cavities have been used for many applications; beam accelerations of high-intensity proton and heavy ion beams, beam manipulations, medical accelerators and anti-proton decelerations. The material has a large permeability and the cavities have bandwidth below approximately 10 MHz. Using an external inductor for reducing the effective inductance of a cavity system, the cavity bandwidth can be moved beyond 10 MHz. The higher harmonic cavity is required in J-PARC Main Ring to enlarge the longitudinal beam emittance before reaching the flat-top energy. For the slow extraction, the emittance growth will be inevitable to suppress the beam instability. For Hyper-Kamiokande neutrino experiment, high-intensity beam with lower peak current will be required to avoid the event-pile-up at a new intermediate detector (IWCD). In this paper, we present the emittance control scenario with the cavity, beam effects on it, and design of a new VHF RF system.
Paper: TUP7625
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUP7625
About: Received: 11 May 2026 — Revised: 21 May 2026 — Accepted: 21 May 2026 — Issue date: 22 May 2026
TUP7628
Precise Frequency tuning of S-band Pulse compressors in High-power operation in the electron and positron injector Linac of KEK
1842
The KEK electron and positron injector linac uses pulse compressors that amplify the high-power RF waves generated from S-band 40 MW klystrons. It is necessary to precisely tune the compressors operating in high-power operation so that their VSWR is minimal and their output power is maximized. We have developed a real-time and labor-saving tuning system for the compressors. The system comprises of a waveform analyzer and a removable and remote-controlled tuner driver. The analyzer calculates in real-time the frequency shift of each compressor comparing its output waveform with the optimal waveform calculated from its input by using the fourth-order Runge-Kutta method. The frequency shift is eliminated by the tuner while monitored pule-to-pulse by the analyzer. In results, all the compressors were tuned easily and precisely.
Paper: TUP7628
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUP7628
About: Received: 11 May 2026 — Revised: 16 May 2026 — Accepted: 17 May 2026 — Issue date: 22 May 2026
TUP7633
Preliminary design of motor drivers for the shenzhen superconducting soft X-ray Free Electron
1857
This report presents the preliminary design of two motor drivers developed for the S3FEL project: one for cavity tuning and the other for coupler adjustment. Both drivers control stepper motors to regulate the resonant frequency and coupling degree of the 1.3 GHz superconducting cavity, respectively. Each driver comprises two functional modules: a motor driver board and a limit signal conditioning circuit. The driver board translates low-power control signals (enable, direction, speed) into high-power outputs to drive the motor. Key design features include optocoupler-based isolation between control and power stages to prevent interference, subdivided stepping for improved positioning accuracy and motion smoothness, and real-time current monitoring to ensure correct output. The limit signal conditioning circuit provides excitation to the limit switches, samples their status, and returns the signals to the controller. Both drivers also supply a holding current to maintain motor position when stationary. Experimental validation confirms that the designed drivers satisfy the operational requirements for precise tuning and coupling control in the S3FEL system.
Paper: TUP7633
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUP7633
About: Received: 13 May 2026 — Revised: 16 May 2026 — Accepted: 16 May 2026 — Issue date: 22 May 2026
TUP7665
Multi-channel high-power desity power supply for klystron solenoid
1913
A control scheme for a high-density multi-channel regulated current power supply based on a compact high-speed PLC is proposed. This scheme adopts a hybrid analog-digital dual-loop control method. The power modules utilize mature commercial modules with built-in analog voltage control loops, while a single PLC constructs the current feedback loops for multiple power modules. The scheme has been successfully applied to multi-channel focusing coil power supplies in an accelerator, featuring extremely high power density, simple interlocking and communication interfaces, and high operational reliability.
Paper: TUP7665
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUP7665
About: Received: 17 Apr 2026 — Revised: 21 May 2026 — Accepted: 21 May 2026 — Issue date: 22 May 2026
TUP7669
Development of a GaN-FET-based fast corrector magnet power supply for the TPS
1923
A modular GaN-FET-based fast corrector magnet power supply has been developed for the Taiwan Pho-ton Source (TPS). The high switching speed of GaN devices enables a significant increase in the output current bandwidth, which improves the response of the fast orbit feedback (FOFB) system and enhances the overall beam stability and photon beam quality of TPS. In the existing FOFB system, the operating current of the corrector magnet power supply is within ±5 A. The developed power supply provides a maximum output current of ±5 A and achieves improved current resolu-tion by optimizing the internal turn ratio of the DC current transformer (DCCT). A digital control architec-ture is implemented, integrating an ADC interface, interlock protection, and a PI controller, and is fully compatible with the TPS control system. With a switch-ing frequency of 250 kHz, the proposed power supply achieves a current control bandwidth of approximately 9 kHz, providing a significant improvement over the existing system.
Paper: TUP7669
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUP7669
About: Received: 15 Apr 2026 — Revised: 15 May 2026 — Accepted: 16 May 2026 — Issue date: 22 May 2026
TUP7681
Advances in large-scale non-evaporable getter coating techniques for the Hefei Advanced Light Facility
1940
The Hefei Advanced Light Facility (HALF), currently under construction, is a fourth-generation synchrotron radiation source operating in the low-energy region (2.2 GeV) and based on diffraction-limited storage ring technology. The storage ring employs a modified hybrid 6BA lattice with a beam emittance of 86.3 pm·rad and consists of 20 achromat cells with a total circumference of approximately 480 meters. To meet the ultra-high vacuum environment of the storage ring, non-evaporable getter (NEG) films are applied to the inner surfaces of the vacuum chambers to provide distributed pumping capability and to reduce surface outgassing and photon-stimulated desorption. Large-scale NEG coating of the HALF storage ring vacuum chambers has been officially initiated. This paper presents an overview of the HALF storage ring vacuum system and provides a systematic description of the large-scale NEG coating system, including the equipment configuration and control system. In addition, a storage system for coated vacuum chambers is described to ensure film quality prior to installation, which provides technical support for subsequent assembly and commissioning.
Paper: TUP7681
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUP7681
About: Received: 15 Apr 2026 — Revised: 16 May 2026 — Accepted: 17 May 2026 — Issue date: 22 May 2026
TUP7705
Sustainability-oriented cryogenic permanent magnet undulator (LN₂-enabled C³-CPMU)
1981
A sustainability-oriented cryogenic permanent magnet undulator, the LN₂-enabled C³-CPMU, has been success-fully demonstrated at the Taiwan Photon Source (TPS). The system is designed to address cryogenic performance, thermal stability, and cost efficiency for high-current storage ring operation (up to 500 mA). The undulator employs a conduction-cooled architecture combined with an LN₂ reservoir-based cooling scheme with simplified flow and pressure control, eliminating the need for dedi-cated cryogenic units. Operating at an intermediate tem-perature of 150–160 K, the system consumes approxi-mately 8 L/h of LN₂. Active temperature control main-tains the magnet temperature within ± 0.08 K under vary-ing beam conditions, ensuring stable magnetic field per-formance. The enhanced magnetic properties at cryogenic temperatures enable shorter undulator periods, while integration with existing facility LN₂ infrastructure sig-nificantly reduces system complexity and operational overhead. These results demonstrate a scalable and ener-gy-efficient solution for next-generation synchrotron and XFEL light sources.
Paper: TUP7705
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUP7705
About: Received: 08 May 2026 — Revised: 14 May 2026 — Accepted: 17 May 2026 — Issue date: 22 May 2026
TUP7722
High-Precision PCB-Based Rotating Coil System for Multipole Magnet Measurements in the 4GSR Storage Ring
2011
For the reduction of beam emittance in a Korea-4GSR project, the storage ring will be equipped with 344 quadrupole, 168 sextupole, and 56 octupole magnets. These multipole magnets require precise magnetic measurements to verify not only the field strength but also harmonic components within the specified tolerances over a good field region with a diameter of 30 mm. To meet this requirement, a PCB-based rotating coil measurement system has been developed. The PCB consists of a 14-layer multilayer structure incorporating both main and bucking coils, enabling high-precision measurement of allowed and higher-order harmonic components. The PCB length was designed to be 660 mm, considering to the effective magnetic length of the 4GSR multipole magnets. To minimize mechanical sag, the rotating shaft was fabricated from ceramic material and positioned at the magnetic field center using a high-precision XY stage with 0.1 μm resolution. The developed rotating coil system achieves a measurement precision better than 5 × 10-4, demonstrating its suitability for high-accuracy characterization of small-aperture multipole magnets in the 4GSR project.
Paper: TUP7722
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUP7722
About: Received: 17 May 2026 — Revised: 18 May 2026 — Accepted: 21 May 2026 — Issue date: 22 May 2026
TUP8007
Commisioning of a new beamline for medical research and radiation hardness testing
2046
The HZB cyclotron accelerator complex provides 68 MeV protons for therapy and related research. The main accelerator is an isochronous sector cyclotron served by two injectors. The treatment room is fixed according to the regulatory agencies and the adjoining experimental station is often overbooked with users for radiation hardness test and dosimetry. To widen the irradiation possibilities, we built up a new beamline for medical research with minibeams and a second target station is prepared for radiation hardness experiments. The setup, possibilities and commissioning for these stations will be presented.
Paper: TUP8007
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUP8007
About: Received: 07 May 2026 — Revised: 16 May 2026 — Accepted: 17 May 2026 — Issue date: 22 May 2026
TUP8014
ATSOA at CERN: A Hands On Accelerator Course in the EURO-LABS Framework
2060
Beyond providing Transnational Access to major Research Infrastructures (RIs) across Europe, the European Laboratories for Accelerator Sciences (EURO-LABS) programme supports advanced training activities. Within this framework, an Advanced Training School on the Operation of Accelerators (ATSOA) is organised at CERN. The school targets students, young researchers, and professionals in the field of accelerator science, offering them a unique opportunity to participate in a week of hands-on training. Five CERN facilities — CLEAR, AD/ELENA, ISOLDE, PSB and LEIR — are involved in the training, allowing participants to familiarise themselves with different accelerator types and particle species. Under the guidance of experienced instructors, they carry out dedicated experiments designed to illustrate key physics concepts and operational principles that can be applied in their own work. This contribution gives an overview of the past schools and an outlook for future courses.
Paper: TUP8014
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUP8014
About: Received: 13 May 2026 — Revised: 19 May 2026 — Accepted: 22 May 2026 — Issue date: 22 May 2026
TUP8032
Towards a Community of Practice in Project Management of Particle Accelerator and Big-Science Projects: The AcceleratePM Initiative
2083
Across Europe, several large-scale particle accelerator and big-science projects — each exceeding hundreds of millions of euros and extending over a decade — are under design or construction, with comparable initiatives underway in the US and China. Despite remarkable scientific achievements, many of them face cost and schedule drift, even when scientific performance targets haven’t been scaled down to maintain cost and timeline. Managing these complex, R&D-driven scientific facility projects requires approaches distinct from even the largest conventional infrastructure undertakings. Recognizing this need, a group of project management (PM) professionals active in particle accelerator initiatives has launched AcceleratePM*, the first international workshop dedicated to PM for accelerator and big-science projects. The first workshop, to be held at CERN in January 2026, will gather all major laboratories and projects to exchange methods, identify common challenges, and define best practices. This contribution presents the workshop scheme, themes, key-findings and planned outcomes, showcasing the largest recent projects – amongst which HL-LHC, ESS, FAIR, F4E – and aiming at informing the management of next-generation initiatives such as the Future Circular Collider (FCC). By building on common issues and most effective solutions, AcceleratePM intends to establish a lasting community of practice, shaping how large scientific projects are conceived, planned, and delivered.
Paper: TUP8032
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUP8032
About: Received: 12 May 2026 — Revised: 19 May 2026 — Accepted: 21 May 2026 — Issue date: 22 May 2026
TUP8033
FAIR Project Management
2087
The Facility for Antiproton and Ion Research (FAIR), currently under construction in Darmstadt, Germany, is one of the largest and most technically challenging research infrastructure projects in Europe. The project combines large-scale civil construction, complex accelerator and infrastructure systems, and scientific installations within a highly interconnected international project environment. A key aspect of FAIR is the implementation of numerous international in-kind contributions. Accelerator and experiment components are developed, manufactured, and delivered by partner institutions from different member states. This model supports scientific collaboration, technology transfer, and the shared financing of complex infrastructure components. At the same time, it creates major organizational and technical challenges, since different engineering standards, procurement processes, national regulations, and planning cultures must be coordinated within one common project structure. The experience from FAIR clearly shows that projects of this scale cannot be successfully realized through technical expertise alone. The large number of interdependencies between procurement, installation, commissioning activities, and scientific but also financing and regulatory requirements creates a level of complexity that can no longer be managed without the highest level of professional and integrated project management. Additional constraints and acceptance. In this context, the FAIR Project Management Office (FAIR PMO) developed over the course of the project from a traditional reporting and controlling function into a central integration and coordination organization. Schedule planning, risk and cost management, quality management, international supplier and in-kind coordination, as well as configuration and data management, have been closely connected within one integrated management framework. A particular focus is placed on linking technical planning with risk and forecasting methods. Schedule planning, technical maturity, delivery status, resource availability, and risk developments are continuously consolidated and evaluated together. In addition, probabilistic and holistic risk and schedule assessment methods are used to represent uncertainties more realistically and to identify critical developments at an early stage. The FAIR experience also highlights the importance of clear project management structures. Methods and tools alone are not sufficient in highly complex research infrastructure projects. What is essential is the ability to identify the key main objectives and to maintain the necessary highest focus to achieve these objectives despite the technical, organizational and strategic interdependencies and complexity. This paper describes the integrated FAIR project management approach and the role of the PMO in coordinating multidisciplinary project activities within the FAIR and GSI campus environment.
Paper: TUP8033
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUP8033
About: Received: 11 May 2026 — Revised: 18 May 2026 — Accepted: 20 May 2026 — Issue date: 22 May 2026
TUV7301
The First Beam Produced by A Conduction Cooled SRF Photogun
2112
We are excited to report on the first beam produced by the world’s first conduction cooled SRF photogun. Over the past five years, Euclid, working in collaboration with Fermilab and Argonne National Laboratory, has been developing a continuous-wave (CW), 1.5-cell, MeV-scale, conduction-cooled SRF photogun operating at 1.3 GHz. The primary objective of this effort is to demonstrate ultra-stable electron beams for UEM/UED applications, enabled by the exceptional shot-to-shot stability achievable with SRF technology compared to room-temperature RF photoguns. Although SRF systems were historically too costly for industrial deployment, two recent advancements: Nb₃Sn coatings and conduction cooling, have dramatically reduced system complexity and operating costs. This SRF photogun can deliver true CW operation while dissipating only ~2 W of RF power, eliminating the need for a high-power RF system and significantly reducing facility footprint. This SRF photogun is also featured with a raised Nb3Sn backwall serving as the photocathode, removing the need for an external cathode insert. In this paper, we present the first beam results from this system along with its cooldown performance, Q-slope behavior, synchronization characteristics, and initial beam parameters.
Paper: TUV7301
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUV7301
About: Received: 12 May 2026 — Revised: 17 May 2026 — Accepted: 21 May 2026 — Issue date: 22 May 2026
TUV7601
High Reliability Digital Control Magnet Power Supply System for SPring-8-II
2115
We have developed new magnet power supply (PS) system for the forthcoming green light source facility, SPring-8-II. Aiming at highly reliable and energy conscious accelerator operations, various PSs with a variety of output current and voltage settings are designed such that (i) each PS with an output current larger than 250 A includes Silicon Carbide switching devices, achieving a conversion efficiency larger than 93% (ii) all PS are embedded with a full digital control system that enables a versatile individual parameter setting, and (iii) main PSs are connected in series to multipole magnets for suppressing PS failures as low as possible. For an individual current setting for the correction of betatron beatings and other purposes, we will prepare auxiliary PSs to add to each individual magnet where it is required. Bipolar PSs for steering magnets have been designed to provide stable output over the whole current range by optimizing our pulse width modulation control. Additionally, we have proposed a new option to adjust an individual current setting by implementing shunt resistors, and also a fast PS switcher that can quickly replace a failed PS with a backup PS without a beam loss is being prepared. We will present these new PS designs and the results of our demonstrations.
Paper: TUV7601
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUV7601
About: Received: 13 May 2026 — Revised: 20 May 2026 — Accepted: 21 May 2026 — Issue date: 22 May 2026
WEP1016
UPDATE ON THE ITN COORDINATED EFFORT FOR ILC TECHNOLOGY DEVELOPMENT IN EUROPE
2231
The ITN-EU consortium, coordinated by CERN with the support of CEA-Saclay and INFN-LASA, is advancing Europe’s contribution to the International Linear Collider (ILC) through the development and validation of high-performance superconducting radiofrequency (SRF) cavities. Activities focus on establishing an optimized production chain, from single-cell R&D to the industrialization of 9-cell cavities. Material procurement and quality control have been completed, and prototype single cells are fabricated and they will be used to assess advanced surface treatment strategies. EU partners are also preparing technical specifications and harmonizing production with Japanese High Pressure Gas Safety requirements. Europe will provide two fully prepared 9-cell cavities for installation in an ILC-type cryomodule assembled and tested at KEK, demonstrating Europe’s integrated and strategic role in the global SRF program.
Paper: WEP1016
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP1016
About: Received: 14 May 2026 — Revised: 18 May 2026 — Accepted: 18 May 2026 — Issue date: 22 May 2026
WEP1314
Dual-RF Phase Control for Adiabatic Energy Ramping in the EIC Rapid Cycling Synchrotron
2265
The Electron-Ion Collider (EIC) Rapid Cycling Synchrotron (RCS) accelerates electrons from 750 MeV to 10 GeV over approximately 64.7 ms. While the baseline design simultaneously ramps both RF voltage and phase, this study evaluates an alternative where RF cavities are divided into two groups, each operating at a fixed 6.5 MV, with the effective voltage synthesized through phase control. In the symmetric scheme (Option A), both groups vary symmetrically about the synchronous phase to provide exact matching of energy gain and synchrotron tune throughout the ramp. Conversely, the asymmetric scheme (Option B) pins one group at the final operating phase while the other varies to supply the required energy gain. The feasibility of Option B is determined by the adiabaticity of the resulting synchrotron tune evolution, with ramp profiles, phase trajectories, and adiabaticity metrics analyzed for both implementations.
Paper: WEP1314
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP1314
About: Received: 13 May 2026 — Revised: 20 May 2026 — Accepted: 21 May 2026 — Issue date: 22 May 2026
WEP1375
NSLS-II Storage Ring Auxiliary Dipole Power Supply
2333
The National Synchrotron Light Source II (NSLS-II) storage ring requires a high-current (400 A), high-voltage (1 kV) dipole power supply system to maintain stable beam operations. Despite the high reliability of the primary system, a 2022 failure event resulted in over 20 hours of beam downtime, highlighting the necessity for enhanced operational resilience. This paper presents the design and implementation of an in-house designed auxiliary dipole power supply system developed to mitigate such risks. The auxiliary system utilizes a modular architecture with N+2 redundancy and high-frequency switched-mode power converters with active power factor correction. This design eliminates large 60 Hz transformers, reducing the system footprint to 10% of the original installation while enabling hot-swappable servicing. A transfer switch ensures a rapid transition from primary to backup systems in under 20 minutes. To maintain stringent orbit stability, the system incorporates a custom DC EMI filter and a series-pass linear amplifier, achieving a measured current stability of 1.71 ppm (DC to 10 kHz). These results demonstrate the system's effectiveness in reducing recovery time and enhancing the overall reliability of NSLS-II beam operations.
Paper: WEP1375
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP1375
About: Received: 11 May 2026 — Revised: 20 May 2026 — Accepted: 21 May 2026 — Issue date: 22 May 2026
WEP1601
Nonlinear chromaticity correction for the interaction region of Super Tau-Charm Facility
2336
The Super Tau-Charm Facility is a new-generation electron-positron collider in the beam energy range of 1-3.5 GeV, with a target luminosity exceeding $5×10^{34}\ \text{cm}^{−2}\text{s}^{−1}$ at 2 GeV using a large Piwinski angle and crab-waist collision scheme. However, the required sub-millimeter vertical beta function ($\beta_y^*$ < 1 mm) induce strong nonlinear chromaticity, which severely limits the momentum aperture of the collider rings and leads to a very short Touschek lifetime. To achieve the necessary 1.5% momentum aperture, local correction of the nonlinear chromaticity from the final‑focus quadrupoles is essential. In this paper, we derive the theoretical origin of the nonlinear chromaticity and demonstrate dedicated measures to systematically mitigate these nonlinearities order by order. Specifically, we present an updated modular linear lattice for the interaction region to facilitate nonlinear chromaticity optimization. The second‑order dispersion at the crab sextupoles is also reduced to nearly zero. By implementing a local chromaticity correction scheme up to the third order, we obtain a momentum aperture of 2% for the interaction region.
Paper: WEP1601
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP1601
About: Received: 13 May 2026 — Revised: 17 May 2026 — Accepted: 17 May 2026 — Issue date: 22 May 2026
WEP4311
Progress on Implementation of a Variable Wedge for FRIB ARIS
2403
A variable wedge system is being developed for the FRIB-Advanced Rare Isotope Separator (ARIS) facility to provide flexible control of beam energy loss. This research evaluates two parallel strategies: a multi-material six-piece solid wedge system and a liquid-filled wedge system. For the solid wedge, the control model and optimization algorithms have been developed and verified, with systematic testing confirming automated control across a 1–20 mrad range. Current efforts focus on exploring sub-mrad regimes (<1 mrad). To address fabrication limitations associated with very thin wedges, a multi-material method was developed in which materials with different densities are selected while maintaining constant areal density. This approach scales the effective thickness range by the density ratio, improving achievable thickness resolution and reducing deviations between calculated and experimentally achievable equivalent wedge configurations. Computational efficiency was further improved by using an L_∞trajectory solver to minimize total actuator displacement. This framework is currently being integrated into the fragment separator simulation code LISE++. In parallel, a liquid-filled wedge model was developed, utilizing a bellows-integrated cylindrical housing to enable continuous density tuning alongside adjustable wedge geometry. Together, these developments provide a robust basis for enhancing rare isotope beam delivery at FRIB.
Paper: WEP4311
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP4311
About: Received: 12 May 2026 — Revised: 18 May 2026 — Accepted: 20 May 2026 — Issue date: 22 May 2026
WEP4602
A Bayesian Optimization Study of the Longitudinal Localized Excitation Slow Extraction for the XiPAF-Upgrading Synchrotron
2482
The longitudinal localized excitation slow extraction method reduces the energy spread of the extracted beam by applying transverse excitation exclusively within specific phase intervals at the edges of the longitudinal phase space of the bunch. For localized square-wave excitation, conventional amplitude modulation formula struggles to achieve uniform beam spill, while the temporal uniformity of the extracted beam is crucial in radiotherapy and related physics experiments. The XiPAF-Upgrading Synchrotron (with a circumference of 39.96 m), developed from Xi’an 200 MeV Proton Application Facility, serves as a dedicated platform for the study and evaluation of single-event effects on core electronics for astronautics. We simulated the localized square-wave excitation slow extraction process using the SynTrack particle tracking code based on the XiPAF-Upgrading Synchrotron's parameters to extract low energy spread beam. Furthermore, a Bayesian optimization method was employed to refine the amplitude modulation curve of the excitation signa, thereby achieving highly uniform beam spill under low-energy slow extraction conditions.
Paper: WEP4602
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP4602
About: Received: 16 Apr 2026 — Revised: 18 May 2026 — Issue date: 22 May 2026
WEP5052
Control of Nonlinear Tune Shifts in SLS 2.0
2692
The Swiss Light Source upgrade, SLS 2.0, is a next-generation storage ring featuring an ultra-low-emittance lattice based on a seven-bend achromat design. Achieving such low emittance requires strong focusing, which in turn generates large negative chromaticities. These are corrected using powerful sextupole magnets, introducing nonlinear effects in the beam dynamics. In particular, amplitude-dependent tune shifts (ADTS) and chromatic tune shifts (CTS) play a significant role. This contribution presents measurements of ADTS and CTS performed using high-precision tune measurements. Furthermore, since SLS 2.0 comprises 12 sectors equipped with 22 octupoles each, the control of ADTS and CTS through the use of octupoles is demonstrated.
Paper: WEP5052
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP5052
About: Received: 15 Apr 2026 — Revised: 28 Apr 2026 — Accepted: 14 May 2026 — Issue date: 22 May 2026
WEP5058
Benchmarking the linear lattice of the ISIS RCS as a foundation for future model-based optimisation
2699
ISIS operates an 800 MeV Rapid Cycling Synchrotron (RCS) delivering protons to neutron and muon targets with a beam power of 0.2 MW. A reliable lattice description is essential for advancing low-loss, high-intensity operation and supports emerging model-driven optimisation enabled by forthcoming Python-accessible controls. A new consolidated low-intensity linear optics model of the ISIS RCS, developed through a continuous programme of systematic measurement-based benchmarking, is presented. Using enhanced analysis of low-intensity turn-by-turn BPM data, multiple optics measurements have been integrated into a single self-consistent lattice representation. This lattice represents a significant advance over earlier design-only or partially benchmarked descriptions, enabling clearer identification of optics discrepancies and guiding targeted correction measures, including improvements to magnet survey and alignment. The resulting reference lattice, implemented in MAD-X/cpymad and cross-checked with PTC-PyORBIT, reproduces low-intensity optics with improved predictive performance, particularly for orbit response and optics control. Benchmarks of the consolidated model, resulting improvements, and planned implementation in model-based optimisation of ISIS RCS operation are presented.
Paper: WEP5058
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP5058
About: Received: 12 May 2026 — Revised: 20 May 2026 — Issue date: 22 May 2026
WEP5076
Tests of commissioning simulation tools in operation of storage ring light sources
2728
The design of 4th generation synchrotron light sources employs such strong quadrupolar and sextupolar magnets, that the motion of electrons in the storage ring is extremely sensitive to the misalignment and the field imperfection of magnets. As a result, it has become common practice to simulate the steps followed during the commissioning of a light source to compare the sensitivity to different types of lattice errors from a beam dynamics point of view and inform the design of the light source. Although there is significant overlap in the algorithms used to commission and to simulate the commissioning of a light source, they typically consist of separate implementations. This work describes the latest developments in the pySC software for commissioning simulations to allow the usage of its tools in a real control system environment for storage rings. Finally, it reports on tests done at the European Synchrotron Radiation Facility Extremely Brilliant Source (ESRF-EBS) to apply said tools to tune the storage ring.
Paper: WEP5076
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP5076
About: Received: 13 May 2026 — Revised: 21 May 2026 — Issue date: 22 May 2026
WEP5127
High-Level Applications for LINAC Commissioning at ELI-NP
2866
The ELI-NP (Extreme Light Infrastructure – Nuclear Physics) Gamma-ray Beam Source (ELI-GBS), currently under construction, employs an 800 MeV linear accelerator (LINAC) to generate high-brightness gamma rays through laser–electron interactions. Its control system is designed as a distributed, EPICS-based architecture, where engineering-level control is provided for devices such as LLRF, modulators, magnets, profile monitors, and current monitors. A set of high-level application tools is required for LINAC beam commissioning, tuning, and the measurement of key accelerator parameters. To meet the beam diagnostic capabilities and performance requirements of the commissioning process, we have developed Python-based high-level application software to support essential commissioning tasks, including gun phase scans, emittance measurements, and beam energy measurements. The software uses the pyepics package to interface with engineering-level device IOCs. To support visualization and offline simulation, a set of Python soft IOCs has also been implemented, enabling realistic emulation of device behavior and data acquisition workflows. The online measurement capabilities of the system will be validated during the upcoming RF Gun commissioning and the subsequent LINAC commissioning phases.
Paper: WEP5127
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP5127
About: Received: 18 Apr 2026 — Revised: 15 May 2026 — Accepted: 22 May 2026 — Issue date: 22 May 2026
WEP5602
A Realistic Proportional-Integral RF Feedback Model for Longitudinal Beam Dynamics Simulation in Electron Storage Rings
2925
Modern fourth-generation storage ring light sources predominantly utilize digital I/Q-based proportional-integral (PI) feedback for their radio-frequency (rf) systems. This paper introduces a dedicated PI feedback model implemented in the STABLE tracking code to enable accurate longitudinal beam dynamics simulations. The model's key innovation lies in its treatment of the continuous transmitter current, which is discretized into electron-bunch-like charge pulses, while the cavity voltage is refreshed on an rf-cycle basis. This methodology offers a more physically accurate model of the beam-cavity-feedback coupling, providing a versatile tool for precise longitudinal beam dynamics studies in single- and multi-rf configurations.
Paper: WEP5602
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP5602
About: Received: 15 Apr 2026 — Revised: 25 Apr 2026 — Accepted: 16 May 2026 — Issue date: 22 May 2026
WEP6006
Gradient-based laser control for end-to-end photoinjector emittance optimization at EuXFEL
2937
Achieving low emittance at the photoinjector is essential for meeting the performance targets of the European XFEL, particularly for high photon energies and future high-duty-cycle operation. Both the temporal structure of the drive-laser pulse and the RF-gun settings contribute significantly to the final beam quality, yet their optimization is complicated by strong nonlinearities in the laser system and complex gun response. We have developed a differentiable, physics-based model of NEPAL, the photoinjector laser of EuXFEL, that enables gradient-driven optimization of the temporal UV pulse shape. The model captures the relevant nonlinearities of the optical chain and allows direct optimization of spectral amplitude and phase to obtain target UV profiles at the photocathode. In parallel, a machine-learning surrogate model is being implemented to optimize the RF-gun operating parameters. Together, these tools provide an end-to-end control framework for emittance reduction at EuXFEL. Initial results demonstrate that the differentiable model enables accurate temporal UV pulse shaping at EuXFEL. Work is ongoing to integrate this approach with ML-assisted gun optimization within the proposed end-to-end control framework.
Paper: WEP6006
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6006
About: Received: 18 May 2026 — Revised: 20 May 2026 — Issue date: 22 May 2026
WEP6007
Accelerator optimization for large parameter numbers embedded in the native FAIR control system environment
2941
The new accelerator complex, FAIR (the International Facility for Antiproton and Ion Research), will soon be commissioned to deliver ion beams using its injector and the GSI accelerator complex. In order to extend the operation of the GSI to include the FAIR and due to some ageing components, a new control system has been implemented. The time- and resource-efficient setup of complex ion beams, a long-standing challenge, has been addressed with a Java-based application called DeviceAutomator. This application handles different optimization routines based on modern machine learning technology. Apart from selecting the most suitable algorithm, challenges arise from data quality and the number of independent parameters. However, since the application is fully integrated into the FAIR control system, all operators in the control room can access and freely configure it without the need for coding. This contribution will describe the implementation and real-life testing of different algorithms: Bayesian, Genetic, and Random Walk. Using a long section of a low-energy ion transport beam line, it has been demonstrated that larger parameter spaces extending well beyond ten parameters present significant challenges for the Bayesian algorithm. However, the genetic optimization routine remains capable of identifying optimal values. It was also evident that a well-chosen optimization routine has the potential to make ion beam setup faster and less labor-intensive.
Paper: WEP6007
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6007
About: Received: 18 Apr 2026 — Revised: 21 May 2026 — Issue date: 22 May 2026
WEP6012
Photoinjector Emittance Optimization using Latent Laser Pulse Representations
2949
We present a beam dynamics study aimed at optimizing the transverse emittance of electron bunches in a photoinjector, motivated by the performance requirements of Free-Electron Lasers. The study is conducted using the accelerator configuration of the Photo Injector Test Facility at DESY in Zeuthen (PITZ), with the overarching goal of developing emittance optimization strategies for the European XFEL photoinjector. To this end, we perform large-scale beam dynamics simulations using the simulation code ASTRA, systematically sampling from a low-dimensional latent representation of temporal laser pulse profiles. This latent space is learned from a broad set of physically plausible pulses using a Wasserstein Autoencoder (WAE), enabling compact and structured exploration of pulse shape variations. The ability to efficiently sample from this representation supports targeted emittance studies that would be computationally prohibitive in the original high-dimensional shaping parameter space. For each simulation, beam quality metrics such as normalized projected emittance and slice mismatches are recorded. The study reveals meaningful correlations between latent coordinates and beam quality, demonstrating the utility of WAE-based representations in guiding laser pulse design. We briefly outline future directions involving neural surrogate models to accelerate beam emittance optimization.
Paper: WEP6012
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6012
About: Received: 15 Apr 2026 — Revised: 21 May 2026 — Issue date: 22 May 2026
WEP6015
Bayesian Optimization of Longitudinal Phase Space in the MAX IV Linac
2957
Reaching design performance in modern particle accelerators is a challenge involving many tasks which are time-consuming and difficult to perform. It is always an advantage to be able to simplify high-level operational tasks and measurements through the assistance of optimization techniques. In this work we applied Bayesian optimization via the XOpt framework with the aim to simplify and enhance the operations in the MAX IV linac. The focus of this work has been longitudinal phase-space optimization using signals from a transverse deflector system. Further, a new approach in the optimization of longitudinal phase-space parameters with the use of virtual diagnostics has been developed and implemented.
Paper: WEP6015
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6015
About: Received: 15 Apr 2026 — Revised: 16 May 2026 — Issue date: 22 May 2026
WEP6017
Towards Fully Automated Transfer Line Commissioning at the CERN Super Proton Synchrotron
2965
Beam commissioning of slow extracted beams from the CERN Super Proton Synchrotron (SPS) to the North Area experimental targets requires trajectory control through multiple transfer lines using corrector magnets—a process that traditionally demands significant expert intervention. Previous work demonstrated the feasibility of applying reinforcement learning (RL) for automated trajectory correction based on secondary emission monitor (SEM) split-foil intensity measurements, successfully centering the beam on target under nominal conditions. However, this approach fails when the beam is lost or its position exceeds the SEM's active surface, and when the corrector magnets' polarities are not known; common sources of uncertainty during commissioning. We present an extended multi-stage optimization scheme that addresses these critical limitations by automating beam threading when the trajectory exceeds the SEMs' acceptance, systematically identifying corrector magnet polarity configurations, and optimizing the impact angle to maximize beam intensity at the fixed-target stations, measured by scintillators arranged around the target. The threading algorithm employs quasi-random search combined with Bayesian optimization (BO) to center the beam in the SEMs, before handing over to the RL controller. The automated polarity determination uses online system identification to resolve sign ambiguities in the correctors, eliminating a common source of commissioning delays when using RL or other dedicated steering algorithms. Finally, BO is used to optimize the position of the movable SEM monitors at the targets' locations, maximizing target intensity.
Paper: WEP6017
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6017
About: Received: 13 May 2026 — Revised: 18 May 2026 — Accepted: 20 May 2026 — Issue date: 22 May 2026
WEP6021
Online Reinforcement Learning for Stripper Foil Aging Compensation at the CERN Low Energy Ion Ring
2973
Stripper foil degradation at the CERN Low Energy Ion Ring (LEIR) poses a significant challenge for beam operations. As the heavy ion beam passes through the stripper foil at the end of the injecting linac, the foil degrades over time, altering the beam energy distribution and reducing the achievable accumulated intensity in the ring. Addressing this operational limitation using traditional control approaches is challenging due to the complex, multi-dimensional nature of the multi-turn injection process. This paper presents a reinforcement learning-based controller to compensate for foil degradation and maintain ring performance. The controller observes longitudinal Schottky spectra encodings and time-of-flight measurements from the linac to adjust the ramping and debunching cavity phases, and electron cooler gun and orbit bump in real-time. We demonstrate that pre-training the agent in a data-driven surrogate model significantly improves both controller performance and sample efficiency during deployment.
Paper: WEP6021
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6021
About: Received: 13 May 2026 — Revised: 19 May 2026 — Issue date: 22 May 2026
WEP6024
Localized Response Basis for Data-Efficient Transverse Beam Distribution Reconstruction Using a Multimode Fiber Relay
2985
Transverse beam imaging in radiation areas can be supported by relaying scintillation light through a multimode fiber (MMF) to a camera placed in a shielded area. However, the MMF scrambles the input, so a trained model is required to recover the beam distribution. This work studies a data efficient calibration method in which measured input and MMF output basis pairs are used as building blocks to synthesize training data for the reconstruction model. After an initial digital micromirror device based validation, the method was assessed using real beam data from CERN CLEAR, where data synthesized from a raster scan basis were used to train a convolutional autoencoder. The best model using this strategy achieved 7.37% mean normalized root mean square error (RMSE) across four transverse beam parameters, compared with 6.02% for a random scan reference model using roughly twice as many fully paired random scan samples. These results suggest that basis-based synthesis training, when combined with suitable beam image priors, can reduce reliance on large random scan MMF calibration datasets by replacing part of the calibration with a controlled scan of fixed size.
Paper: WEP6024
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6024
About: Received: 13 May 2026 — Revised: 19 May 2026 — Accepted: 19 May 2026 — Issue date: 22 May 2026
WEP6031
Experimental Evaluation of a Digitizer Designed for ACCT Beam Current Transformers
2995
To integrate the signals of beam current transformers into accelerator control systems, particle accelerators require high-performance digitizers with optimized bandwidth, sampling rate, and dynamic range. They must be accurate and reliable. And they should be easy to deploy and operate. A specialized digitizer was developed to interface the Bergoz Instrumentation ACCT sensor and its analog front-end electronics to an accelerator control system. It allows waveform acquisition preserving the quality of the analog signal and controls the ACCT configuration. Communication is implemented over Ethernet through a simple command protocol, and an EPICS soft IOC is provided. The digitizer was tested with two ACCTs installed at the CHUV Oriatron Linac and a third at the METAS electron beamline. Results demonstrate improved signal-to-noise ratio, adaptability to multiple beam types, and simplified deployment compared to general-purpose digitizers.
Paper: WEP6031
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6031
About: Received: 11 May 2026 — Revised: 18 May 2026 — Accepted: 20 May 2026 — Issue date: 22 May 2026
WEP6046
Upgrade of the Beam Loss Monitoring System for the Unilac Heavy Ion Linear Accelerator at GSI
3025
The beam-loss monitoring system of the UNILAC heavy-ion linear accelerator is based on measuring the beam current at multiple locations along the beamline. Signals from beam–current transformers are amplified, converted into pulse trains and counted within a defined time window. The system has proven to be robust and operationally safe. The ongoing upgrade aims to replace the current-to-frequency converters and the entire digital subsystem while preserving the established operational principle and the analog front-end. Most important reasons are ageing of the electronics, the need for improved scalability, flexibility and safety, and last but not least, alignment with the new GSI/FAIR controls architecture. The new system operates under the supervision of a System Control Unit (SCU), the standard front-end platform of the GSI/FAIR control system. It is controlled by the Front-End Software Architecture (FESA) and White Rabbit. Once configured, the FPGA-based hardware operates autonomously to ensure high reliability and fail-safe behaviour. Here we describe the system architecture, its modular hardware, firmware architecture and the software interface.
Paper: WEP6046
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6046
About: Received: 28 Mar 2026 — Revised: 22 Apr 2026 — Accepted: 15 May 2026 — Issue date: 22 May 2026
WEP6091
Commissioning the Passive Structure Wakefield Dechirper on CLARA
3128
A passive energy dechirper has been installed on CLARA, a 250 MeV electron beam user facility at Daresbury Laboratory. The device, comprising two orthogonal sets of planar dielectric-lined waveguides, is designed to manipulate the longitudinal phase space of the electron bunch, reducing energy spread and thereby delivering higher quality beams for user experiments. We present preliminary results from initial commissioning of the dechirper with the CLARA beam, including measurements of the wakefields excited and changes in longitudinal phase space due to the dechirper. We outline plans for further measurements and discuss how the dechirper will support upcoming user programs.
Paper: WEP6091
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6091
About: Received: 11 May 2026 — Revised: 19 May 2026 — Issue date: 22 May 2026
WEP6095
Python Based Control and Diagnostic Systems for AREAL Linear Accelerator
3140
AREAL linear accelerator constructed in Yerevan, Armenia, is designed to generate low-emittance, ultra-short electron beam pulses to enable advanced research in novel accelerator technologies, advanced coherent radiation sources, and dynamics of atomic and molecular processes. This paper presents an overview of the complex Python-based control system developed for the AREAL accelerator. It details the associated hardware components, software architecture, and auxiliary support applications. Additionally, future development plans for the control system and its integration with AREAL upgrading capabilities are discussed.
Paper: WEP6095
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6095
About: Received: 01 Apr 2026 — Revised: 17 May 2026 — Accepted: 17 May 2026 — Issue date: 22 May 2026
WEP6099
Status of accelerator automation in the community: classification, survey results, and the role of ai and machine learning
3144
The increasing complexity of particle accelerators and the growing demand for operational efficiency have intensified the focus on automation in accelerator control systems. However, there is still a lack of a common language to describe and compare the level of automation across different facilities. This article presents a generic classification scheme for accelerator automation, defining five distinct levels ranging from basic operational assistance to full autonomy. To assess the current state of automation in the accelerator community, a structured survey was conducted during the 14th Workshop on Accelerator Operations (WAO 2025). Responses from major laboratories indicate that more than one third of accelerators currently operate at the lowest level 1 (operational assistance), and no facility has yet reached full automation. However, projections show a clear trend toward higher levels within the next decade. Key drivers include optimization algorithms for autotuning, finite-state machines, and closed-loop feedback systems. This study provides both a conceptual framework and a snapshot of current implementation practices, supporting a shared understanding of accelerator automation across the community.
Paper: WEP6099
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6099
About: Received: 15 Apr 2026 — Revised: 19 May 2026 — Accepted: 20 May 2026 — Issue date: 22 May 2026
WEP6100
Commissioning of the FAIR Control Centre
3148
The FAIR Control Centre (FCC) has been purpose-built on the GSI campus to meet the complex operational demands of the FAIR/GSI large scale accelerator facility. It hosts the Main Control Room (MCR), seminar and meeting rooms of various sizes, offices, and dedicated technical rooms. The 640 m² MCR is an open, collaborative workspace for accelerator experts, experiment teams, and technical staff. It offers a 24/7 ergonomic environment with ad-vanced acoustic and climate control, height-adjustable consoles, and a water-cooled IT infrastructure. In addi-tion to the console displays, the fully digital MCR fea-tures ca. 110 m² of high-resolution LED overview dis-plays for system-level visualization. Construction of the MCR was completed in November 2025. Console installation began on December 8th, fol-lowed by IT installation and commissioning in early 2026. Initial operation of the first consoles was per-formed in late February, with full MCR operation target-ed for June 2026. The GSI accelerators will be controlled from the FCC for the beam time starting in September. We report on the FCC key features and the project sta-tus on its path to completion, with an emphasis on com-missioning.
Paper: WEP6100
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6100
About: Received: 18 Apr 2026 — Revised: 17 May 2026 — Issue date: 22 May 2026
WEP6101
Extended Maintenance and Gradual Replacement of MIL-1553-based Field Network at GSI
3151
The control system of the GSI accelerator complex dates back to the early 1990s. It is based on a derivative of the MIL-1553 field bus, providing around 1 Mbit/s throughput and deterministic real-time operation. Although a modern control architecture with smart front-ends (System Control Units, SCUs), Ethernet, and White Rabbit is now widely deployed at GSI, several hundred devices still depend on the legacy network and protocols. The ageing electronics and limited bandwidth provide strong motivation to migrate to the new control system. However, an upgrade is limited by various constraints: strict real-time operation, existing software architecture, physical space and available power sources. Therefore, operation of the legacy interfaces must be ensured for at least another decade while a unified migration strategy is hard to find. In this contribution, we present a generic approach for extending the lifetime of the existing MIL-1553-based systems and gradual replacement of their components. This includes upgrades of bus controllers, device controllers, the bus itself as well as a new Modbus/TCP-based solution for simple devices.
Paper: WEP6101
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6101
About: Received: 28 Mar 2026 — Revised: 15 May 2026 — Issue date: 22 May 2026
WEP6102
A Python Framework for Integration of Measurements into the EPICS Control System
3154
Many measurements in accelerator physics require dedicated scans of parameters, such as the main frequency of the RF system for chromaticity measurements or a variation of quadrupole strength for beta function measurements, etc. Such measurements cannot be performed by simply reading an instrument, but require a certain measurement procedure. These measurements are typically implemented as scripts, as they are often written by staff or students whose task is the measurement itself. For reusability and maintainability, however, an integration into the EPICS control system is favoured. This has multiple benefits such as the easy archiving of results in the central database or the integration of the measurements into the standard operator panels. To allow non expert staff and students to easily build measurements exposed via the EPICS control system, we built a framework in Python to implement such measurement routines as EPICS input-output-controllers (IOC). This framework allows the author of such measurements to focus on the measurement itself and still benefit from an EPICS integration without the need for extensive knowlege in EPICS IOC development.
Paper: WEP6102
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6102
About: Received: 13 May 2026 — Revised: 22 May 2026 — Issue date: 22 May 2026
WEP6103
IFMIF-DONES control systems and testing platform
3158
IFMIF-DONES is an accelerator-based neutron source under construction in Granada, Spain. Its goal is to generate an intense and continuous flux of fusion-like neutrons to qualify the materials to be placed in nuclear-fusion reactors. Meeting its ambitious availability targets imposes stringent reliability requirements on all components, particularly transversal systems such as Control Systems. To address this, a dedicated testing platform is being developed to validate architectural and technological choices. Key aspects under evaluation include the EPICS IOC deployment model (container-based) and orchestration solution (currently evaluating Proxmox HA, Docker Swarm and Kubernetes). It is also envisaged to integrate the existing DONES prototypes into the testing platform. The testing platform will deliver value across all project phases by reducing risks, improving consistency, and enhancing readiness. In early stages, it supports operation of the DONES prototypes and minimizes risks by validating design choices. During development and commissioning, it will foster standardization through shared tools and procedures, easing integration and enabling early operator training. In operation and maintenance, it will uphold accessibility and usability standards, as well as long-term reliability and maintainability. This contribution will present the proposed architecture of the IFMIF-DONES control systems and report on the design and current progress of the testing platform.
Paper: WEP6103
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6103
About: Received: 13 May 2026 — Revised: 19 May 2026 — Issue date: 22 May 2026
WEP6104
RF-API: A Modular Control Framework in EPICS for RF Systems at CLARA
3162
The CLARA facility has been upgraded in Phase-II to deliver electron bunches of up to 250 MeV using a standing wave photo-injector gun, four linac structures and a fourth harmonic lineariser cavity. A transverse deflecting cavity (TDC) is also employed to measure key bunch parameters. To support reliable and efficient operation, a comprehensive RF Application Programming Interface (RF-API) has been developed within the EPICS control system. This API provides an intuitive interface for operators and serves as a foundation for higher-level machine control applications. It also enhances operational safety by monitoring unintended performance or configuration deviations in the RF systems and automatically alerting RF experts to potential degradation. This paper presents the design, capabilities, and performance of the RF-API and its associated user interface.
Paper: WEP6104
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6104
About: Received: 01 May 2026 — Revised: 19 May 2026 — Issue date: 22 May 2026
WEP6106
Upgrade plan for the ESRF Fast Orbit Feedback
3169
The Fast Orbit Feedback (FOFB) at the ESRF was initially developed in 2010. During the upgrade of the storage ring for the Extremely Brilliant Source (EBS) project in 2019, the FOFB architecture was adapted to the new ring, but no significant functional improvements were introduced. The current system is now obsolete in several respects, including the hardware and development tools and practices. A full refurbishment of the FOFB is now being planned. The main objectives are to enhance system performance through improved correction algorithms and reduced latency, to enable local orbit correction for individual beamlines with the possible integration of XBPM measurements, and to ensure compatibility with future BPM system upgrades. Particular emphasis is placed on long-term maintainability through the adoption of modern software development methodologies and the use of open-source or non-proprietary technologies as much as possible.
Paper: WEP6106
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6106
About: Received: 04 May 2026 — Revised: 16 May 2026 — Accepted: 17 May 2026 — Issue date: 22 May 2026
WEP6111
Highlights of Spill Optimization System Usage at GSI and Progress of Controls Integration
3180
At the GSI SIS18 synchrotron, the Spill Optimization System (SOS) has been established as a key tool to improve spill quality during resonant slow extraction. During the 2025 beam times, the SOS was routinely used with the radio frequency knock-out (RF-KO) method for several experimental campaigns, enabling improved spill stability and more efficient beam delivery to users under various operational conditions. The experience gained during these runs has also guided the ongoing integration of the SOS into the FAIR control system environment. This integration enables time-multiplexed operation of the system for multiple experiments running in parallel, leading to more efficient operation. It also aims to streamline the setup and monitoring of slow extracted spills through tighter coupling with accelerator controls and unified human and machine interfaces. This contribution summarizes the operational highlights from the 2025 beam times and discusses observed improvements in spill stability and beam usability for the experiments. In addition, the current status and outlook of the full control system integration efforts are presented.
Paper: WEP6111
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6111
About: Received: 11 May 2026 — Revised: 18 May 2026 — Issue date: 22 May 2026
WEP6114
Towards fast orbit correction: a modular and extensible global orbit feedback system
3186
At SESAME, the orbit correction system was originally implemented in MATLAB and operated at a correction rate of 0.2 Hz. While adequate for initial deployment, this setup proved insufficient for production environments due to its limited speed and scalability. To address these shortcomings, a complete implementation was carried out in the C programming language, resulting in a high-performance, modular orbit correction system capable of significantly faster update rates and real-time operation. The new system architecture supports seamless integration with FPGA-based acceleration, feedforward control strategies, and advanced techniques such as Tikhonov regularization. It also features a flexible framework that allows easy addition or modification of control and estimation algorithms. A Simulink-based simulation is used to enable offline validation and safe testing of control strategies. In addition, an EPICS IOC and a Qt-based GUI are implemented for process variable handling. This upgrade represents a significant advancement in orbit correction infrastructure, delivering a scalable and extensible solution aligned with the operational needs of modern synchrotron light sources.
Paper: WEP6114
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6114
About: Received: 13 May 2026 — Revised: 19 May 2026 — Issue date: 22 May 2026
WEP6115
Automated software workflow for accelerator control systems using containerization
3189
Managing large number of Input / Output Controllers (IOCs) and Graphical User Interfaces (GUIs) in a multi-network facility is challenging, since there are several resources of failures large scientific facilities may face in their life cycle, including hardware failures in servers and networks, operating system issues like high CPU and memory usage, and application issues such as crashes and memory leaks. A new software workflow is developed and released at SESAME that solves the preceding issues. The workflow includes containerizing software in independent units using Docker, orchestrating those units from a central manager using Kubernetes, managing installing, releasing, and rolling back of the deployments using Helm, and automating the process through a well-defined pipeline using continuous deployment using Jenkins. This workflow is immune to human error as every step is fully automated. Also, this workflow reduced development and deployment time significantly and enhanced IOCs availability. Currently, SESAME’s accelerator control system is almost fully managed by the described workflow, while beamlines integration is in progress.
Paper: WEP6115
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6115
About: Received: 13 May 2026 — Revised: 18 May 2026 — Issue date: 22 May 2026
WEP6118
Upgrade of the LHC Low-Level RF Beam-Control for the Digital Frequency Distribution over White-Rabbit
3199
In preparation for the High-Luminosity LHC (HL-LHC) era, a significant upgrade to the LHC Low-Level RF (LLRF) Beam-Control system is being implemented. The installation of crab cavities during Long Shutdown 3 (LS3, 2026-29), together with the obsolescence of existing components, necessitates a modernization of the LHC LLRF architecture. The upgraded Beam-Control system - based on MicroTCA and VME hardware - replaces the frequency program and reconstructs a digital master RF. These frequencies are transmitted over a White-Rabbit (WR) network in the form of Frequency Tuning Words (FTW) to maintain synchronization among the distributed RF devices. This approach enables a scalable RF distribution infrastructure across the accelerator complex and experiments, with improved phase stability and reduced noise. This paper presents the motivation and design of the upgraded system, including the method used to achieve robust phase synchronization over WR. Finally, it shows results obtained from a dedicated test with beam acceleration in the LHC.
Paper: WEP6118
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6118
About: Received: 28 Apr 2026 — Revised: 18 May 2026 — Issue date: 22 May 2026
WEP6120
An automated production test suite for capacitive alignment sensor conditioning electronics
3203
The High Luminosity upgrade of the Large Hadron Collider (HL-LHC) at CERN requires exceptional alignment accuracy of accelerator components to reach the luminosity targets and to ensure reliable beam operation. This accuracy is achieved with the help of the Full Remote Alignment System (FRAS), which employs a capacitive Wire Positioning System (WPS) to monitor the position of magnets, RF cavities, and other accelerator components relative to a stretched, conductive, reference wire. Each WPS sensor measures distance offsets with respect to this reference wire with sub-micron-level resolution. The sensors are connected via dedicated cables to specially designed WPS conditioning electronics for signal processing and data acquisition. These modules operate as application specific cards within CERN’s Distributed Input/Output Tier (DI/OT), a standardized framework designed for modular electronics operating in radiation-exposed environments. To support the large-scale production and verification of over 400 WPS conditioning modules, an automated Production Test Suite (PTS) has been developed. The PTS streamlines firmware programming, automates test execution and ensures full traceability through integration with CERN's Enterprise Asset Management (EAM) platform and the Engineering Data Management Service (EDMS). This paper presents the design and validation of the PTS for WPS conditioner electronics, focusing on hardware–software integration and its role to enable reliable production testing for the HL-LHC.
Paper: WEP6120
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6120
About: Received: 10 May 2026 — Revised: 17 May 2026 — Accepted: 17 May 2026 — Issue date: 22 May 2026
WEP6127
GSI Operation Statistics in the FAIR Construction Phase (2012 - 2025): Trends, Failures and Lessons Learned
3222
We present operational statistics for the GSI accelerator complex during the FAIR construction phase from 2012 to 2025, covering UNILAC, SIS18, ESR, HEST and CRYRING@ESR. The analysis is based on beam-time schedules, availability monitoring, and fault annotations from the Operator Logbook (OLOG). During the last five years, failure entries were systematically reviewed and reclassified to ensure consistent data quality and enable reliable long-term trend evaluation. The main performance indicator discussed is accelerator availability, determined from scheduled operation periods and fault-related downtimes. The evaluated data were used as a quantitative input in the recent POF-5 evaluation process (2028-2034), where they clearly supported refurbishment and consolidation needs at GSI. A technical roadmap was established this year to prioritize these measures according to their impact on stable beam delivery towards FAIR accelerators.
Paper: WEP6127
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6127
About: Received: 15 Apr 2026 — Revised: 17 May 2026 — Issue date: 22 May 2026
WEP6130
Asset Management Workflows for cSTART using Snipe-IT
3226
For the cSTART project the Institute for Beam Physics and Technology (IBPT) at the Karlsruhe Institute of Technology (KIT) introduced with Snipe-IT a new system to manage all accelerator related components. As the new components arrive, one of the first step is entering them into the asset database, which creates a unique identifier. This identifier is then also used during the quality inspection process as the main reference. The asset-to-asset associations possible with Snipe-IT provide a simple and efficient method for structuring the components in cabinets and along the storage ring. The flexible custom fields allow to track references to other data sources, which provide the more technical information such as CAD drawings, cable routing and device documentation. In addition, it also allows to track component specific information. This contribution describes the established workflows, status and lessons learned using a generic IT asset management system for accelerator component management.
Paper: WEP6130
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6130
About: Received: 12 May 2026 — Revised: 18 May 2026 — Issue date: 22 May 2026
WEP6131
ON-THE-FLY SCANNING: IMPROVING SCAN TIME OF XAFS AT BM08-XAFS/XRF BEAMLINE
3229
In this work, we present the use of PandABox timing module to implement position-based and time-based on- the-fly scanning to continuously acquire data at the X-ray Absorption Fine Structure (XAFS) and X-ray Fluorescence (XRF) beamline of SESAME synchrotron light source. For position-based scanning, we first developed a module that automatically partitions the user-defined energy and Bragg angle ranges into sub-intervals. Within each sub-interval, the energy-angle mapping is linearly approximated to main- tain accuracy within acceptable margins. The method then integrates the position encoding of the Double Crystal Monochromator (DCM) Bragg angle with the synchronous triggering of multiple detectors, including ionization cham- bers (ICs) and a KETEK SSD detector. For time-based scanning, PandABox is pre-configured to generate triggers at fixed time exposure time intervals. Improvements, per- formance and comparative results are also discussed in this work. Keywords: on-the-fly scanning, QEXAFS, DAQ, Pand- ABox, linear fitting, XAFS/XRF
Paper: WEP6131
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6131
About: Received: 31 Mar 2026 — Revised: 20 May 2026 — Issue date: 22 May 2026
WEP6145
The MYRRHA phase 1 MTCA.4-based LLRF system
3251
The first 100 MeV stage of the MYRRHA superconducting RF linear accelerator is under construction in Mol, Belgium. The machine produce an instantaneous proton beam current of 4 mA and represents the first step toward the construction of the MYRRHA Accelerator-Driven System (ADS). Such a machine presents several technical challenges for the control of its RF cavities. First, the required field stability is ≤ 0.1% in amplitude and ≤ 0.1° in phase to avoid excessive beam losses. The high loaded quality factor (QL = 2.3×10⁶) and the need to modulate the beam at 250 Hz require sophisticated field- and detuning-control techniques to keep RF consumption and stability within specifications. Finally, since the maximum allowed beam-trip duration is less than 3 seconds, real-time fault detection and recovery techniques must be implemented in the Low-Level RF (LLRF) controller. To meet these stringent requirements, the MTCA.4 standard and the DAMC-DS5014DR direct-sampling AMC were chosen. In this proceeding, the LLRF control strategy foreseen for the MYRRHA phase 1 will be presented. The current status of the firmware, software, and analog front-end will also be discussed.
Paper: WEP6145
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6145
About: Received: 15 Apr 2026 — Revised: 03 May 2026 — Issue date: 22 May 2026
WEP6148
Detuning estimation for a doubly-fed normal-conducting gun
3258
At the European Free-Electron Laser (EuXFEL) superconducting linac, a revised normal-conducting gun design with symmetrical feed was successfully installed and tested. Thermal expansion of the solid copper body dominantly affects the detuning transients of this cavity. To improve accuracy, and add time resolution over the duration of a pulse, we implemented and tested an observer that estimates the resonance frequency over time using a parameter-identified white-box model of the RF network. Results were validated against forward and reflected power couplers, cavity voltage, and an algebraic stationary approximation.
Paper: WEP6148
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6148
About: Received: 08 May 2026 — Revised: 18 May 2026 — Issue date: 22 May 2026
WEP6149
Narrowband Active Noise Control for Continuous Wave Operation of TESLA Cavities
3262
TESLA 9-cell elliptical cavities are used in the accelerators of the European XFEL and LCLS-II. The high duty cycle upgrade study for EuXFEL and the LCLS-II-HE program target loaded Quality factors of 6e7 and beyond, leading to RF cavity half bandwidths below 11Hz. Stable operation in these conditions heavily relies on active RF resonance control, as required RF drive power to maintain amplitude and phase lock surpasses amplifier max ratings if detuning is not compensated. To counteract mechanical vibrations, e.g. introduced by rotational machines in the proximity of the accelerating modules, a dedicated narrowband active noise control algorithm was introduced in previous work. This proceeding presents CPU based implementations and latest test results obtained at the Cryomodule Test Bench (CMTB) at DESY and LCLS-II at SLAC, where the stable operation gradient of a cavity could be increased from 9 to 15MV/m without violating RF control limits.
Paper: WEP6149
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6149
About: Received: 10 May 2026 — Revised: 20 May 2026 — Issue date: 22 May 2026
WEP6150
Digital low level RF system for Elettra 2.0
3266
The new digital electronics of the four Radio Frequency (RF) plants for Elettra 2.0 (E2.0) is fully designed in house, both hardware and firmware. The Digital Low-Level Radio Frequency (DLLRF) works on a non-IQ sampling technique and it is benefiting from the huge internal development of a System On Chip (SoC) Field Programmable Gate Array (FPGA) boards realized for the electron beam position monitor electronics. Each RF plant will have its own machine protection system based on FPGA board to minimize the interlock intervention time. Initial tests of these new electronics have been carried out during last run of Elettra, however the complete commission is carried out using the RF power plant available in the laboratory. This paper presents the design choices and the performed tests that confirm the achievements of the system’s specification.
Paper: WEP6150
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6150
About: Received: 05 May 2026 — Revised: 19 May 2026 — Accepted: 19 May 2026 — Issue date: 22 May 2026
WEP6153
Planned upgrade of the CERN Proton Synchrotron Beam Control system
3270
The CERN Proton Synchrotron (PS) Low Level RF (LLRF) system is composed of cavity controllers, which regulate the field in the cavities, and a beam control, in charge of maintaining the required longitudinal beam specifications and managing the injection and extraction processes. The current beam control system, implemented using mainly analogue electronics in NIM and VME formats, is set to be replaced by modern digital platforms that have been deployed in other machines in the complex. This upgrade aims for a redesigned, more centralized and standardised system. The new compact digital module will result in significantly reduced hardware requirements and improvement in diagnostics and maintenance. This paper provides an overview of the system’s architecture, hardware, firmware, and development plan, focusing on the control loops and the interaction between the module and other components in the system.
Paper: WEP6153
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6153
About: Received: 13 May 2026 — Revised: 19 May 2026 — Issue date: 22 May 2026
WEP6156
Surrogate models for the European XFEL operation
3277
Numerical beam dynamics simulation codes are essential for designing and studying particle accelerators, but their computational cost can make them unsuitable for online use and predictions during operations. The use of machine learning-based surrogate models can significantly reduce the required computational time whilst still providing an accurate prediction of the beam properties. In this paper, we present the first results on the training of surrogate models for the prediction of the longitudinal phase space (LPS) at the European XFEL. Finally, we discuss the potential application of such models in the development of a virtual diagnostic tool for use in the European XFEL control room as well as a fast estimator for the final LPS based on the user-provided compression parameters.
Paper: WEP6156
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6156
About: Received: 13 May 2026 — Revised: 20 May 2026 — Issue date: 22 May 2026
WEP6158
Turning Logbook Data into Operational Insight with a new Statistics Service at GSI and FAIR
3285
It is common practice during accelerator operation to continuously document all relevant machine states and activities. At GSI Helmholtz-Center for Heavy Ion Research, this is done using an electronic logbook (OLOG) developed in-house and adapted to the specific requirements of accelerator operations, allowing shift crews to record failure events, setup times, and other important information in high detail. A new service, currently under development, aims to simplify the on-demand access to relevant statistics and is being prepared to include data from the Facility of Antiproton and Ion Research (FAIR) as its operations gradually commence in the upcoming beamtimes. This service is built as two layers, a backend layer communicating with the database to pull entries from the logbook system and to calculate statistics from them, and a frontend layer handling user requests as well as providing a graphical depiction of these statistics and their raw data. This report presents the current logbook system used at GSI and FAIR and introduces the new statistics service to be implemented as an assessment tool.
Paper: WEP6158
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6158
About: Received: 15 Apr 2026 — Revised: 14 May 2026 — Accepted: 15 May 2026 — Issue date: 22 May 2026
WEP6163
Inovesalib: A Modular Vlasov-Fokker-Planck Solver Framework
3289
The numerical solution of the Vlasov–Fokker–Planck (VFP) equation is a well-established method to simulate the dynamics of electron bunches in storage rings, including their self-interaction through wake fields. Inovesa is an efficient VFP solver architecture that enables accurate simulations of phase space evolution, capturing phenomena such as coherent synchrotron radiation (CSR) and the micro-bunching instability on standard desktop hardware. Building on this foundation, we introduce Inovesalib, a redesigned and extensible library version of Inovesa that exposes the core VFP solver as a modular C++ API and provides a Python wrapper for seamless integration into user workflows. Inovesalib decouples the solver core from application logic and offers a plugin architecture that allows users to implement custom algorithms without modifying the underlying solver. The redesigned structure turns Inovesa from a standalone application into a flexible simulation framework, suitable for integration into optimization pipelines, machine-learning workflows, and custom tools. We present the library architecture and demonstrate its use in both C++ and Python.
Paper: WEP6163
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6163
About: Received: 12 May 2026 — Revised: 18 May 2026 — Issue date: 22 May 2026
WEP6170
Pipelines: A Node-Based Editor for Streamlined Optimisation Prototyping in the Control Room
3300
Development shifts on accelerators are usually time-constrained and infrequent. Meanwhile, control room PCs are not designed for scrappy R\&D, and maintaining multiple workflows with python scripts is prone to error. GUI apps have been successfully deployed and used in the past to perform optimisation at accelerator facilities. However, bookkeeping can become difficult in complex tasks. Furthermore, support is missing for pre-optimisation steps such as response matrix measurements used in Slow Orbit Feedback (SOFB) machine learning algorithms. A PySide node-based visual editor has been developed and tested in the Diamond control room. A logical heirarchy of blocks define processes to perform and an inspector window allows the user to fine-tune blocks to their needs. Separate processes are spawned when compute or time-intensive blocks are run, keeping the main UI thread responsive. An optimisation problem is tackled using the app to demonstrate its usefulness.
Paper: WEP6170
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6170
About: Received: 12 May 2026 — Revised: 18 May 2026 — Issue date: 22 May 2026
WEP6171
Automated RF Conditioning on CLARA
3304
In this paper we present the design and deployment of the software tools used for the automated parallel conditioning of 7 RF cavities on CLARA (Compact Linear Accelerator for Research Applications). The software tools consist of 4 distributed tools with the following responsibilities: Control, Acquisition, Visualisation, and Communication. In combination, these tools enabled the round-the-clock conditioning of all RF cavities with minimal operator intervention, achieving operating parameters for beam commissioning activities.
Paper: WEP6171
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6171
About: Received: 11 May 2026 — Revised: 20 May 2026 — Issue date: 22 May 2026
WEP6306
Unsupervised Anomaly Detection and Channel Attribution with Variational Autoencoders at the Advanced Light Source
3320
We present an unsupervised pipeline that learns a compact representation of beam-on machine state at the ALS, detects anomalies preceding beam-loss events, and highlights the responsible channels for operator diagnosis. Archiver data are resampled to a uniform time grid, filtered to beam-on intervals using stored current, and pruned by variability and principal-component analysis. A variational autoencoder with residual encoder-decoder stacks is trained on the standardised PV vectors; the global anomaly score and the per-PV attribution are both derived from per-PV reconstruction z-scores, so the score is an exact decomposition of the channel ranking. We apply the pipeline to 34 beam-loss events from the 2025 ALS user run; in several cases it surfaces early-stage anomalies in the PV subsystems that subsequently led to the beam dump, indicating a framework can act as an early-warning aid for operators.
Paper: WEP6306
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6306
About: Received: 13 May 2026 — Revised: 22 May 2026 — Issue date: 22 May 2026
WEP6603
LLRF Prototype Design for the 1.3 GHz Cryomodule of the Shenzhen Superconducting Soft X-ray FEL
3324
This paper presents the design and preliminary test results of a Low-Level Radio Frequency (LLRF) prototype system developed for the 1.3 GHz standard cryomodule of the Shenzhen Superconducting Soft X-ray Free Electron Laser (S3FEL). The system is implemented within an MTCA.4 platform, integrating eight RF controller boards for superconducting cavity field acquisition and microwave excitation control to stabilize the RF field and ensure steady electron beam acceleration, alongside two tuner controller boards for driving four coupler motors, four cavity tuner motors, and eight piezoelectric actuators (PZTs). A high-speed peer-to-peer (P2P) backplane bus enables real-time communication between RF and tuner control boards. The report outlines the hardware architecture of this modular LLRF system and discusses initial functional and performance tests, demonstrating its suitability for meeting the precise stability requirements of the S3FEL project.
Paper: WEP6603
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6603
About: Received: 13 May 2026 — Revised: 20 May 2026 — Issue date: 22 May 2026
WEP6604
Digital LLRF Control System for a High-Repetition-Rate Superconducting Linac
3327
The development of high-repetition-rate superconducting linear accelerators for advanced light sources imposes stringent demands on the performance of the Low-Level Radio Frequency (LLRF) control system. This report presents the design, implementation, and operational results of a high-precision LLRF system developed for the Dalian Advanced Light Source (DALS) injector—a 1 MHz superconducting linac. The system employs a digital feedback architecture based on a field-programmable gate array (FPGA), enabling high-speed I/Q modulation and demodulation, vector summation, and low-latency feedback control to address the narrow bandwidth challenge posed by superconducting cavities with loaded quality factors up to 4.3×10⁷ (half-bandwidth ~15 Hz). High-resolution piezo actuators are integrated for active cavity tuning. During commissioning in August 2025, the system successfully stabilized ten superconducting cavities, supporting beam operation at over 100 MeV, 1 MHz repetition rate, and 0.1 mA current. Closed-loop amplitude and phase stabilities of better than 0.02 % and 0.02 ° were achieved per cavity, with total voltage maintained steadily at 110 MV. The results demonstrate the system’s robustness and precision, providing a valuable reference for future LLRF systems in next-generation high-repetition-rate light sources.
Paper: WEP6604
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6604
About: Received: 12 May 2026 — Revised: 20 May 2026 — Issue date: 22 May 2026
WEP6606
Research and Development of Fast Orbit Feedback System at HALF storage ring
3330
Hefei Advanced Light Facility (HALF) Fast Orbit Feedback (FOFB) system uses 80 fast corrector magnets to stabilize beam orbit measured at 80 Beam Position Monitors (BPM). In order to achieve a closed-loop bandwidth of 500Hz, the system operates with a correction rate of approximately 20kHz. A distributed fast orbit feedback system is designed to control the instability of the beam orbit in storage ring at the submicron level. We design the high-performance feedback processor based on FPGA, and a system verification platform is designed, fabricated, and tested using feedback algorithm in the laboratory. To ensure the reliability of system operation, a system monitoring software is designed based on EPICS. This paper presents the status of the FOFB system, including preliminary open-loop test results.
Paper: WEP6606
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEP6606
About: Received: 13 May 2026 — Revised: 21 May 2026 — Issue date: 22 May 2026
WEV5002
Bunch lengthening with double- and triple-rf systems for MAX4U
3367
MAX IV is engaged in the design of a major upgrade to its 3 GeV ring, called MAX 4U. The upgrade aims at an improvement in light source performance to maintain MAXIV’s competitive edge beyond the end of this decade. In this contribution, we report on the studies of the performance of double- and triple-rf systems for bunch lengthening with MAX4U parameters. The stationary bunch profiles and longitudinal instabilities thresholds were evaluated with semi-analytical methods and benchmarked with macroparticle tracking simulations for different settings of the harmonic rf cavities.
Paper: WEV5002
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEV5002
About: Received: 12 May 2026 — Revised: 21 May 2026 — Accepted: 22 May 2026 — Issue date: 22 May 2026
WEV6003
Moonlight on the Serengeti: Casting (Digital) Shadows with SIMBA, PUMBA, LAURA and Friends
3379
Digital shadows offer a methodology for bridging physical particle accelerators with their virtual counterparts, enabling predictive modelling, automated control, and improvements in facility design and implementation. A digital shadow for the CLARA accelerator is being developed, integrating two complementary tools: LAURA, an ontology-driven description language for particle accelerator lattices; and SIMBA, a simulation framework that utilises LAURA-defined models to perform start-to-end particle tracking using multiple tracking codes. Together, LAURA and SIMBA form the simulation backbone of a digital shadow, providing a consistent and extensible representation of the accelerator. This architecture is further augmented by pyCATAP, a controls middle layer that interfaces with accelerator control systems, PUMBA, a procedural automation framework for running complex operational tasks and standardising I/O data structures, and SARABI, a framework for generating soft EPICS IOCs from a LAURA lattice.
Paper: WEV6003
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-WEV6003
About: Received: 11 May 2026 — Revised: 20 May 2026 — Accepted: 22 May 2026 — Issue date: 22 May 2026
TUI4M00
Accelerator Research for Proton Therapy
3410
Proton therapy is a powerful tool in the fight against cancer. The number of accelerators has increased tremendously over the last years. Patients are treated now at over 125 facilities world-wide, which is an excellent example of an extremely successful technology transfer from fundamental research to healthcare. Depending on the tumour species, local tumour control can reach very high levels, e.g. more than 96% for uveal melanoma. To minimize side effects and maintain tumour control, new treatment modalities like FLASH or Minibeams are investigated. For FLASH, dose rates should be higher than 40 Gy/s with treatment times below 0.5 s. Minibeams aim for spatial fractionation of the beam. Experiments on cells, organoids and animals have been promising. These new irradiation forms create challenges for the existing and future accelerators: Developments in beam delivery, beam adaptation, and dosimetry are necessary. This paper describes changes on control system, beam shutters, and beam scattering systems which allow now irradiation times of 10 ms with a precision in dosimetry of better than 3% for a Spread-Out Bragg Peak at HZB. The set-up of a target station for minibeams will be presented.
Paper: TUI4M00
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-TUI4M00
About: Received: 07 May 2026 — Revised: 18 May 2026 — Accepted: 21 May 2026 — Issue date: 22 May 2026
THP2011
Vertical alignment of the SLS 2.0 storage ring
3442
The alignment of girders and individual magnetic elements according to the tight design specifications is of paramount importance for achieving the ultimate performance of the SLS 2.0 storage ring (SR) which is consisting of a large number of SR optics defining permanent magnets. As a result, alignment errors can easily overstrain the very limited capabilities of the electromagnetic dipole corrector magnets. In order to enable a fast realignment during commissioning the girders are vertically remote adjustable allowing for a realignment within +-0.5mm (backed by simulation) with stored beam and running fast orbit feedback based on previously taken survey data (Beam-Assisted Girder Alignment). A linear encoder based vertical positioning system monitors the relative girder-to-girder motion. In addition, the orbit correction system helps to identify errors of individual magnets on the girders.
Paper: THP2011
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-THP2011
About: Received: 13 May 2026 — Revised: 21 May 2026 — Issue date: 22 May 2026
THP2028
SOLEIL 2025 Operational Status
3483
SOLEIL, the French 2.75 GeV third-generation synchrotron light source, continues to operate as a high-performance research infrastructure supporting both academic and industrial communities. This contribution reviews the 2025 operational achievements, with emphasis on accelerator stability, availability, and the delivery of reliable photon beams to 29 beamlines. Key performance indicators and operational trends are presented, together with an analysis of major events and the mitigation strategies implemented to strengthen machine robustness. Significant progress in addressing component obsolescence is reported, including advances in BPM electronics, RF systems, and the global control-system upgrade. Updates on the LINAC modernization programme are provided, along with the use of the current SOLEIL accelerator as an integrated test platform to validate critical technologies for the forthcoming facility upgrade. Preparatory activities for SOLEIL II are outlined, including a progress report for bunch-per-bunch transverse feedback system, development and preparation to the qualification of new 352 MHz low-HOM RF cavities, the 1.4 GHz fourth-harmonic system, and upgraded control architectures, highlighting the technical readiness for the next-generation machine.
Paper: THP2028
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-THP2028
About: Received: 20 May 2026 — Revised: 20 May 2026 — Issue date: 22 May 2026
THP2135
Status of the automated activation of GaAs photocathodes at Photo-CATCH*
3711
Photocathodes based on the III-V seminconductor GaAs are used as photo-electron sources to supply spin-polarized electron beams for accelerator applications. In order to achieve a sufficient electron yield, a thin surface layer of cesium combined with an oxidant is applied onto the cathode surface in a process called the cathode activation. It is typically done manually by an experienced operator. This contribution presents the current status in the development and testing of an adaptive algorithm for automated activation at the Photo-CATCH test stand.
Paper: THP2135
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-THP2135
About: Received: 15 Apr 2026 — Revised: 18 May 2026 — Issue date: 22 May 2026
THP3309
Modernizing the AWA facility: enhanced beam quality and capabilities for high-gradient RF and beam physics research
3801
The Argonne Wakefield Accelerator (AWA) is a 1300 MHz, 65 MeV normal-conducting photoinjector LINAC supporting a broad research program in high-gradient RF acceleration, beam physics, and AI/ML-based accelerator operations. The facility produces electron bunches span-ning 1 pC to 100 nC, including high-charge (~100 nC, ~25 kA), high-brightness (~hundreds nm emittance), and arbitrarily shaped formats, and delivers beam to 5 device-under-test zones along two primary experimental beam-lines. Over the past decade the AWA has undergone exten-sive modernization, including replacement of the drive gun with an RF-symmetrized photoinjector; upgrade of the drive laser from a 248 nm excimer to a 262 nm Ti:sapphire system; transition to a distributed EPICS-based control system; and deployment of a digital LLRF system developed by the LBNL BACI group. Recent experiments have demonstrated accelerating gradients >300 MV/m in X-band structures, peak cathode fields >400 MV/m, and beam-driven RF power generation >565 MW. Near-term plans include RF-symmetrized linac cavity replacements and an asymmetric EEX beamline upgrade. A proposed AWA-II upgrade would double the beam energy to ~130 MeV, further expanding the facility’s reach for high-gradient RF and beam physics research.
Paper: THP3309
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-THP3309
About: Received: 13 May 2026 — Revised: 21 May 2026 — Issue date: 22 May 2026
THP3620
Photocathode Preparation Studies Based on a Photocathode In-Situ Research Apparatus
3839
The photocathode in-situ research apparatus integrates preparation, characterization, and environmental control under ultra-high vacuum to prevent surface contamina-tion, establishing a real-time “preparation-monitoring-regulation” closed-loop for high-performance photocath-odes such as Cs2Te. Following comprehensive commis-sioning, which is utilized for Cs2Te photocathode prepara-tion, CsBr protective layer deposition, and temperature-dependent performance measurements. In-situ grazing-incidence wide-angle X‑ray scattering (GIWAXS) charac-terization at the Shanghai Synchrotron Radiation Facility (SSRF) revealed that the crystal structure of sequentially deposited Cs2Te photocathode changes synchronously with the QE improvement, validating the apparatus for studying high QE photocathodes.
Paper: THP3620
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-THP3620
About: Received: 22 Apr 2026 — Revised: 20 May 2026 — Issue date: 22 May 2026
THP4008
Longitudinal optimization of HL-LHC beams in the CERN SPS
3865
In the framework of the High-Luminosity (HL) upgrade of the Large Hadron Collider (LHC), the bunch intensity from the injectors must be doubled with respect to the nominal design value. To meet these demands, the Super Proton Synchrotron (SPS) has been extensively upgraded to deliver $2.3 \times 10^{11}$ protons per bunch in multiple trains of up to 72 bunches. An extensive campaign of beam studies in the SPS demonstrated that all required parameters in terms of bunch intensity and length, as well as their spreads, are achieved for the relevant production schemes. Fine-tuning of the longitudinal beam properties, including controlled emittance blow-up and optimization of the higher-harmonic RF system, was essential. Sporadic non-rigid dipole oscillations, likely induced during the longitudinal blow-up, have been investigated in detail. Spectral analysis of the measured bunch position reveals prominent lines at multiples of 600 Hz, crossing the frequency band in which the blow-up is active. The impact on beam quality is evaluated, and possible mitigation strategies are discussed.
Paper: THP4008
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-THP4008
About: Received: 13 May 2026 — Revised: 20 May 2026 — Issue date: 22 May 2026
THP4017
A new beam dynamic design procedure
3896
The beam dynamics design of a Radio Frequency Quadrupole (RFQ) is usually optimized to match the beam parameters at the entrance and exit of the cavity. This design step defines the vane geometry—such as the distance from the vane tips to the beam axis, the vane-tip radius, the type and amplitude of the modulation, and the modulation length—and also provides the inter-vane voltage for the next stage: the RF design. Based on the inter-vane voltage profile along the cavity, the 2D cross-section is then adjusted to match the local cutoff frequency of the quadrupole mode, typically by modifying the quadrant volume where the magnetic field is dominant. In this paper, we propose a new approach to RFQ beam dynamics design. Instead of considering only the geometry near the beam axis, the full 2D cross-section—including the quadrant region—is integrated directly into the beam dynamics optimization. The resulting inter-vane voltage can then be obtained by preserving the magnetic-field region’s area along the cavity, which may simplify the manufacturing process.
Paper: THP4017
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-THP4017
About: Received: 29 Apr 2026 — Revised: 19 May 2026 — Issue date: 22 May 2026
THP4026
Update on ESS Medium Beta cavities at INFN LASA
3919
INFN LASA is involved in delivery four MBcavities to ESS Eric as part of the Italian In-Kind Contribution to the “operation Phase”. The cavities have been fabricated and tested naked before the integration into the He-tank. After successful performance verification, the cavities have been integrated and finally validated at DESY AMTF before their delivery to CEA for installation into the cryomodule. We report the results of the fabrication and tests as well as lessons learned.
Paper: THP4026
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-THP4026
About: Received: 13 May 2026 — Revised: 19 May 2026 — Issue date: 22 May 2026
THP4031
Cooling skid, thermal characterization and simulations for the ARGITU RFQ at ESS-Bilbao
3929
The ARGITU RFQ at ESS-Bilbao is a 352.2 MHz, 4-vane RFQ that will accelerate protons from 45 keV to 3.0 MeV. The RFQ is a 3.1 meters long structure machined in OHFC copper of high purity, and no brazing has been used to assemble the vanes that conform each of the four segments. The cooling of the structure is carried out by cooling channels that runs longitudinally along the vane tips and transversal in the vacuum grid region. In a first stage, the RFQ will operate at a maximum duty cycle of 1%, and for this stage a first version of the water cooling skid has been designed, built and tested. The vane cooling channels in this setup runs in series from segment to segment allowing a simpler design. A dedicated chiller that provides great stability and control has been integrated in the system, as well as water flow and temperature valves and sensors monitored using IO link technology. The cooling water skid, the tests performed with the RFQ and their correlation with FEM simulations are described in this paper. The dynamic tuning of the RFQ during conditioning and operation are also described.
Paper: THP4031
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-THP4031
About: Received: 12 May 2026 — Revised: 19 May 2026 — Issue date: 22 May 2026
THP4037
FFA magnet prototype for high power pulsed proton driver
3944
The Fixed Field Alternating Gradient (FFA) accelerator is a natural candidate for a high-power pulsed proton driver, although no high-power FFA has yet been constructed. As a critical component of the accelerator, the main magnets have been the subject of particular study. Operational flexibility, in terms of machine optics, over a large range is an essential feature of such a machine. In order to explore this in more detail a dedicated FFA prototype magnet has been designed and manufactured. This magnet was manufactured and delivered to the Rutherford Appleton Laboratory (RAL) in the UK in April 2025, and field measurements are subsequently planned to establish its characteristics. This paper will discuss the design, manufacture, and measurement plans of the prototype magnet.
Paper: THP4037
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-THP4037
About: Received: 13 May 2026 — Revised: 19 May 2026 — Accepted: 21 May 2026 — Issue date: 22 May 2026
THP4048
Design and Optimization of a Fast Electrostatic Chopper for FLASH Proton Therapy Radiobiology Experiments.
3980
FLASH proton therapy has shown the potential to reduce normal-tissue toxicity while maintaining tumor control by delivering radiation in ultra-high dose-rate pulses (>40 Gy/s). However, more radiobiology experiments are needed to better understand the subjacent mechanism and optimize its application beam parameters. To explore this regime using the Cyclotron at Centro Nacionalicémoste de Aceleradores in Seville, we have developed a fast electrostatic chopper for length beam structure manipulation in order to be able to produce short (~1 um) and high intensity pulsed beams. In this paper, we present the design and optimization of this device, intended to generate well- defined beam pulses for radiobiology experiments in the FLASH regime. Electromagnetic simulations were performed with CST Particle Studio to define the electrode geometry, determine the required operating voltage, and carry out tolerance studies for the mechanical design. The designed chopper was integrated into a full TOPAS model of the external cyclotron beamline to evaluate the need of additional subsystems such as a collimator and to optimize the operational parameters. First studies carried out with this model are also presented.
Paper: THP4048
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-THP4048
About: Received: 13 May 2026 — Revised: 22 May 2026 — Issue date: 22 May 2026
THP4069
Super-FRS controls for commissioning
4032
The Super-FRS project is a state-of-the-art spectrometer for nuclear physics studies, currently being built at the Facility for Antiproton and Ion Research (FAIR). The Super-FRS will serve as the workhorse of nuclear physics research, using intense primary beam from the synchrotrons of FAIR to produce, select, and identify rare isotopes. In addition to its technical capabilities for the production and separation of nuclei, the Super-FRS will support a wide range of nuclear physics experiments through the integration of dedicated experimental equipment or adaptation of the ion-optical layout. To achieve this flexibility and enable commissioning in 2027, extensive work on controls, data acquisition, and modelling is underway. In order to preserve the versatility of the Super-FRS as a platform for diverse investigations while ensuring full interoperability between the control, experimental data acquisition, standard beam diagnostic components, and analysis systems, the software suite must allow the seamless combination of experimental data with beam-diagnostic information, enabling the use of standard operational tools (operator-driven and automated).
Paper: THP4069
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-THP4069
About: Received: 13 May 2026 — Revised: 21 May 2026 — Issue date: 22 May 2026
THP4094
Modifications of the high-energy beam transport at GSI and its subsystems for FAIR
4083
The High-Energy Beam Transport at GSI (GSI-HEBT) is a system of transfer lines which delivers heavy ion beams from the SIS18 synchrotron to various experiments, the fragment separator and the storage rings ESR and CRYRING@ESR. The High-Energy Beam Transport for FAIR (FAIR-HEBT) will also branch off from the GSI-HEBT. This connection is currently under construction and requires several modifications in the GSI-HEBT to accommodate FAIR beamline devices within tight space constraints. Furthermore, FAIR will be operated from a new, fully digital control room. Therefore, all remaining analog devices of GSI-HEBT had to be digitized, in particular the cameras of the scintillating screens and the fast current transformers. The power converters for the magnets in GSI-HEBT, which are needed for beam transport to FAIR, are currently being upgraded to FAIR standard. These modification of GSI-HEBT will be discussed in this paper in detail.
Paper: THP4094
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-THP4094
About: Received: 16 Apr 2026 — Revised: 16 May 2026 — Accepted: 16 May 2026 — Issue date: 22 May 2026
THP4097
Robust real-time optimization of SIS18 injection using Gaussian Process MPC
4095
We present advancements in the data-driven Model Predictive Control (MPC) framework for optimizing multi-turn injection (MTI) into the SIS18 synchrotron. Building on our prior work on safe, sample-efficient optimization, we systematically investigate the impact of current noise and transverse emittance fluctuations. By incorporating realistic error models derived from dedicated measurements of fluctuations on injected current and emittance into simulations, we demonstrate that the Gaussian Process model effectively filters random uncertainty, maintaining robust operation where standard numerical optimizers degrade. Furthermore, we report on the successful deployment of the framework during live SIS18 tuning. The controller autonomously adjusted injection parameters, demonstrating reliable convergence, enhanced efficiency, and a substantial reduction in tuning iterations compared to model-free RL methods, which often face challenges in real-world applications. These results establish data-driven MPC as a powerful tool for real-time optimization in noisy, high-stakes accelerator environments, setting the stage for safe learning-based control across FAIR facilities.
Paper: THP4097
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-THP4097
About: Received: 15 Apr 2026 — Revised: 20 May 2026 — Issue date: 22 May 2026
THP4115
Alternative fabrication process for carbon stripper foils used in particle accelerators
4142
CCarbon foils are widely used in particle accelerators to produce ion beams with high charge states. These strip-per foils are primarily deposited on a soluble substrate, (e.g. NaCl or betaine-sucrose) that is subsequently dis-solved to provide a free-standing foil. For use in acceler-ators, the free-standing foils need then to be mounted on a metallic frame, a delicate and time consuming opera-tion. In this paper, we propose an alternative fabrication process, where the foils are deposited directly onto a metallic supporting frame. The process involves the surface preparation of plain copper plates, in-situ Ar-H2 plasma treatment to enhance adhesion, deposition of the carbon film by magnetron sputtering, and removal of the copper from the central part of the supporting plate by chemical etching, to create an aperture for the passing ion beam. We describe the different fabrication steps, the quality control approach used to assess the carbon areal density, the thermal outgassing rate, and the porosity of the foils. The first beam test results using CERN-produced carbon stripper foils, obtained with Pb54+ ion beams at 4.2 MeV/u at LINAC 3, are presented.
Paper: THP4115
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-THP4115
About: Received: 13 May 2026 — Revised: 19 May 2026 — Issue date: 22 May 2026
THP4310
Slow extraction beam commissioning for the Mu2e experiment at Fermilab
4164
Following the successful completion of the Muon g-2 experiment run at Fermilab, the Muon Campus facili-ty has been reconfigured from delivering 3 GeV muon beams to the g-2 storage ring to providing slow-extracted 8 GeV proton beam spills for the Mu2e ex-periment. The first full-scale commissioning run with slow extraction was conducted during the 2025 run, followed by the second run in early 2026. We present the results and current status of this commissioning campaign.
Paper: THP4310
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-THP4310
About: Received: 12 May 2026 — Revised: 18 May 2026 — Issue date: 22 May 2026
THP4311
Second generation Fermilab Main Injector 8 GeV beamline collimation final design, installation and commissioning
4168
A novel transverse beam collimation system has been installed and commissioned in the Fermilab Main Injector 8 GeV beamline. The new collimation system compliments existing collimators and helps ensure the Fermilab Main Injector and Recycler accelerators are capable of handling the increased beam power promised from the Fermilab PIP-II upgrade, currently underway. This paper will present the final design and installation of the collimation system as well as initial results from its commissioning.
Paper: THP4311
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-THP4311
About: Received: 13 May 2026 — Revised: 20 May 2026 — Accepted: 21 May 2026 — Issue date: 22 May 2026
THP5303
Application of the nonlinear optics from off-energy orbits method at the SIRIUS Storage Ring
4188
The applicability of the Nonlinear Optics from Off-Energy Closed Orbits (NOECO) method to the SIRIUS storage ring is investigated. Off-energy orbit response matrices (OEORMs) were measured and used for sextupole strength calibration through a Levenberg-Marquardt (LM) fitting procedure with Tikhonov regularization. The fitted strengths reproduced the measured chromaticities with reasonable accuracy and were consistent with control system estimates. Analysis of the OEORM Jacobian revealed strong correlations among sextupole family signatures, indicating significant quasi-degeneracies in the inverse problem. Machine experiments and model-based simulations showed that localized perturbations are redistributed across correlated families, especially in the presence of small optics mismatches. The results indicate that OEORM-based calibration is feasible at SIRIUS, although its resolving power is fundamentally limited by parameter correlations and model imperfections.
Paper: THP5303
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-THP5303
About: Received: 13 May 2026 — Revised: 20 May 2026 — Issue date: 22 May 2026
THP5614
Nonlinear optimization of the HALF storage ring lattice
4300
The Hefei Advanced Light Facility (HALF) is a 4th-generation storage ring light source currently under construction in Hefei, China. Its storage ring utilizes a modified hybrid 6BA lattice. The HALF storage ring employs off-axis injection and is planned to operate in a full-coupling mode, which requires a large dynamic aperture and control of amplitude-dependent tune shifts. This paper presents the optimization of the nonlinear dynamics for the HALF storage ring, introducing a new version of the lattice and an alternative lattice solution featuring a larger dynamic aperture.
Paper: THP5614
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-THP5614
About: Received: 11 May 2026 — Revised: 21 May 2026 — Issue date: 22 May 2026
THP5671
Simulink analysis with new coupling beta measurement for vertical test at IRIS
4409
There have been concerns regarding the uncertainties of Q-factor measurements in vertical test system when the coupling beta is too low or too high. Forward and reverse power readings can be affected by cross-contamination in the bidirectional coupler and by re-reflection from the circulator, resulting in increased measurement uncertainty. This uncertainty becomes more significant when the cavity is far from critical coupling, because the dissipated power is determined from the difference between the forward, reverse, and transmitted powers. To address this issue, we are recently developing a new method for measuring the coupling factor, β, based on the emitted power ratio between the input coupler and the pickup coupler. When the coupler geometry is mechanically fixed, the external quality factors (Q_e,Q_t) of each coupler remains constant. During cavity field decay, the emitted power ratio of the reverse power, P_r, and the pickup power, P_t, remains constant. this emitted power ratio makes it possible to calculate the coupling factors of both couplers with the transfer function. This method reduces the sensitivity of coupling-factor measurements to RF power measurement errors. Simulink simulations were performed to evaluate the validity and accuracy of the proposed method. The Simulink model provides improved understanding and quantitative evaluation of measurement uncertainties in the vertical test system.
Paper: THP5671
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-THP5671
About: Received: 13 May 2026 — Revised: 18 May 2026 — Accepted: 21 May 2026 — Issue date: 22 May 2026
FRI6M01
From femtosecond to attosecond RF field control
4464
In the past two decades, RF controls have improved by two orders in magnitude achieving meanwhile sub-10 fs phase stabilities and 10e-4 amplitude precision. Analog-to-digital-converters (ADCs) are the main limitation for further increase in detector resolution. Alternative architectures are therefore needed to overcome this limitation. The presented work covers a novel application of the suppressed-carrier detector, which extends conventional heterodyne receivers and improves the residual time jitter of the regulated RF-field in the cavity far below 1 fs. A practical implementation of the proposed principle is presented. The setup was used to drive a superconducting RF cavity at 1.3 GHz frequency at a Cryo Module Test Bench (CMTB) at a gradient of 8MV/m. The measured out-of-loop residual time jitter of the RF field was 189 as (10Hz to 1MHz). The limiting factors of the setup have been identified by feeding the measurements to a system model. In conclusion, a general discussion about future steps is presented.
Paper: FRI6M01
DOI: reference for this paper: 10.18429/JACoW-IPAC2026-FRI6M01
About: Received: 12 May 2026 — Revised: 20 May 2026 — Accepted: 20 May 2026 — Issue date: 22 May 2026