experiment
MOPM021
Proof-of-principle experiment to reconstruct the trajectory of dust grains interacting with the LHC beams
330
Interactions of dust grains with the LHC beams cause beam losses that can trigger premature beam aborts or even quenches of superconducting dipoles. While the simulated motion and ionisation of dust grains inside the proton beam are in good agreement with measured beam-loss data, a direct measurement of the dust movement is not available. A novel method was developed that reconstructs the trajectory of a dust grain based on the different beam loss profiles of transversely displaced bunches. A proof-of-principle experiment to validate the method using a thin wire to simulate the dust grain was performed in June 2024 at the LHC. This paper describes the beam experiment, compares the achieved displacements with simulations, and shows the reconstructed trajectories. Finally, it is discussed how the method can be applied for real dust events occurring during LHC operation.
Paper: MOPM021
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPM021
About: Received: 28 May 2025 — Revised: 01 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
MOPM025
Advancing the feasibility study of the ALICE fixed-target experiment using crystal-assisted halo splitting with HL-LHC lead ion beams
346
The Large Hadron Collider (LHC) at CERN is the world’s most powerful particle accelerator, capable of colliding proton and lead ion beams at energies up to 7 ZTeV. ALICE, one of the LHC’s key experiments, is designed for studying heavy-ion collisions. A proposed fixed-target experiment within ALICE involves directing a portion of the beam halo, extracted using a bent crystal, onto an internal target positioned a few meters upstream of the detector. For proton beams, this configuration has already demonstrated effective particle flux delivery to the target while operating safely alongside standard beam-beam collisions. However, with lead ion beams, the beam halo comprises nuclei of varying charge, mass, and magnetic rigidity, posing additional operational challenges. This paper presents an analysis of the expected performance, based on multi-turn particle tracking simulations using a detailed LHC model.
Paper: MOPM025
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPM025
About: Received: 28 May 2025 — Revised: 05 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
MOPM079
Automated conditioning utilizing machine-learning: first experimental results
506
The conditioning of room temperature cavities is a long process. Additionally, since the cavity or auxiliary equipment can be damaged, constant supervision or extensive safety precautions are required. To reduce the workload for everyone involved and to increase the efficiency of the conditioning process, it was decided to develop a machine learning algorithm with the goal of fully automated conditioning in mind. The initial model was trained on available data of the low energy-domain (up to 500 W). Since it was possible to expand the data to higher power levels during conditionings in 2024, the algorithm is now trained for power levels up to 30 kW. In this paper, the challenges of training with different power scales, as well as the first experimental results shall be discussed.
Paper: MOPM079
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPM079
About: Received: 28 May 2025 — Revised: 29 May 2025 — Accepted: 30 May 2025 — Issue date: 05 Nov 2025
MOPM114
Estimation of systematic errors in the experiment on precise mass measure of Y(1S)-meson on the VEPP-4M collider
579
Error analysis and estimation of accuracy in the experiment on precise mass measurement of Y(1S)-meson on the VEPP-4M with KEDR detector collider was presented. The resonant depolarization technique with laser polarimeter was used for beam energy calibration.
Paper: MOPM114
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPM114
About: Received: 28 May 2025 — Revised: 08 Oct 2025 — Accepted: 08 Oct 2025 — Issue date: 05 Nov 2025
MOPM115
Y(1S)-meson rest mass measurement on the VEPP-4M collider
582
A new high precision measurement of the Y(1S)-meson rest mass is being carried out at the VEPP-4M collider using the KEDR detector. The resonant depolarization method with the laser polarimeter has been employed for the absolute calibration of the beam energy. In the paper resent status of the experiment is discussed.
Paper: MOPM115
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPM115
About: Received: 28 May 2025 — Revised: 08 Oct 2025 — Accepted: 08 Oct 2025 — Issue date: 05 Nov 2025
MOPS003
Towards operational reality with laser assisted charge exchange
585
Laser-Assisted Charge Exchange (LACE) is being developed at the Spallation Neutron Source (SNS) as a potential replacement for injection foils, which are not expected to endure in the 10 MW beam power regime. Previous experimental demonstrations have achieved highly efficient charge exchange of H⁻ ions to protons for beam durations of up to microseconds. A refined method, capable of scaling to full millisecond duty cycles, has been experimentally validated and aligns with theoretical models. The current phase of development focuses on optimizing laser and beam parameters for LACE using a newly installed, flexible experimental setup in the High-Energy Beam Transport (HEBT) line at SNS. This setup takes advantage of the upgraded SNS beam energy of 1.3 GeV, offering greater flexibility in selecting laser wavelengths for the experiments. Simultaneously, efforts are underway to design a LACE ring injection system that fits within the spatial constraints of the existing SNS ring injection region. This presentation will provide an update on the progress of these developments.
Paper: MOPS003
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPS003
About: Received: 23 May 2025 — Revised: 31 May 2025 — Accepted: 31 May 2025 — Issue date: 05 Nov 2025
MOPS005
Adiabatic capture in high-intensity, high-power rings
592
Finding the optimal RF voltage ramp to capture coasting beams in high intensity rings has been the subject of ongoing study for many decades. We are motivated to revisit the topic with a view to capturing coasting, stacked beams in a future high intensity, high power FFA. However, the results have general applicability. We compare various voltage laws including linear, bi-linear and iso-adiabatic through simulation and experimentally, making use of the ISIS synchrotron. Making use of longitudinal tomography, we seek to establish the voltage program that minimises the captured beam emittance.
Paper: MOPS005
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPS005
About: Received: 28 May 2025 — Revised: 04 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
MOPS007
Characterisation and mitigation of RF knockout
600
Beam stacking is a key advantage of Fixed Field alternating gradient Accelerators (FFAs) for high-intensity applications. During stacking, one beam is stored as a coasting beam at the extraction energy while another, incoming beam is accelerated. However, the beam loss mechanism termed RF knockout can occur during stacking and undermine gains in extracted beam current. The accelerating RF program of the incoming beam can cause cumulative displacements in the stored coasting beam and result in significant beam loss. To ensure that beam stacking is a viable technique to extract highest intensities from an FFA, methods to avoid the loss from RF knockout must be established. This study presents results from a series of experiments at the ISIS proton accelerator to characterise and, crucially, to mitigate RF knockout and ensure successful beam stacking with no loss.
Paper: MOPS007
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPS007
About: Received: 27 May 2025 — Revised: 03 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
MOPS008
Introduction of key performance indicators for the GSI accelerator facility
604
The GSI Facility consists of several accelerators, offer-ing the distinctive capability to provide different ion beams with varying characteristics to a range of experi-ments simultaneously. In order to facilitate the monitor-ing of machine performance across diverse beam produc-tion chains and experiments, a Key Performance Indica-tor (KPI) metrics has been introduced. The CRYR-ING@ESR team has completed an initial KPI assessment of the ion storage ring and developed procedure to ana-lyse beam diagnostic data offline. Initial analysis has identified lacking information and features in the FAIR Archiving System (FAS) and data structures to support automated tracking of machine performance. This paper will present detailed definitions of KPIs to enable quanti-tative, beam-based accelerator performance measure-ment, an assessment of their implementation and an outline of future developments.
Paper: MOPS008
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPS008
About: Received: 27 May 2025 — Revised: 05 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
MOPS011
Improvement on beam-based alignment methods by reliability weighted average technique
607
Accurate determination of magnet centres seen by beams is the key to a successful commissioning of a particle accelerator storage ring. In this paper, several techniques to improve the beam-based alignment for a circular accelerator storage ring are introduced. Firstly, a formula to propagate the uncertainties from linear fitting is given. Secondly, a reliability weighted averaging technique based on uncertainties are applied to mitigate the impact of outliers. Thirdly, studies show that the accuracy and precision of quadrupole centre locations can be refined by using multiple corrector magnets in the process. Finally, to improve the efficiency when using multiple correctors, a monte-carlo technique is utilized. The resulting distributions of all BPM-to-Quad offset residuals derived from simulations are presented.
Paper: MOPS011
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPS011
About: Received: 27 May 2025 — Revised: 31 May 2025 — Accepted: 01 Jun 2025 — Issue date: 05 Nov 2025
MOPS018
Demonstrating the feasibility of a double-crystal fixed-target experimental physics setup through the TWOCRYST project in the LHC
627
The TWOCRYST proof-of-principle experiment at the LHC is an initiative to demonstrate the feasibility of a double-crystal setup for fixed-target physics experiments. Such a setup could enable spin precession studies of charmed baryons in the TeV energy range in the HL-LHC era. Major milestones in this project have recently been achieved, including the successful construction and testing of critical components such as the 4~mm and 7~cm long bent silicon crystals required, a new combined fixed-target and crystal goniometer for accurate angular positioning, and two Roman pot stations equipped with advanced tracking detectors. This contribution summarizes the status of the hardware, the results from the first machine development studies to prepare for the measurements with the crystals in 2025, and a detailed plan for the beam tests with the full TWOCRYST setup.
Paper: MOPS018
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPS018
About: Received: 19 May 2025 — Revised: 03 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
MOPS020
The TWOCRYST fibre tracker: A detector to characterize precession crystals at the LHC
635
A fixed-target experiment using two bent crystals is proposed to study the magnetic and electric dipole moments of short-lived charm baryons with unprecedented precision in the LHC. This will be achieved exploiting crystal channeling into a first crystal to extract the beam halo and then into a 7 cm long silicon crystal capable of inducing a measurable spin precession to the particles of interest. TWOCRYST is a proof-of-principle machine test scheduled for 2025, to test this setup and address the feasibility of the final experiment under LHC beam conditions. One main goal is the study of the channeling efficiency in this long crystal at TeV energies, requiring a 2D detector in movable Roman pots. The TWOCRYST Fibre Tracker, coming from the LHC's ATLAS-ALFA experiment, is a high-precision tracking detector with ten layers of crossing scintillating fibers coupled to multi-anode photomultipliers, and read out using compact front-end electronics. Intense refurbishment work was required on to adapt the detector to the purposes of TWOCRYST. This contribution summarizes the tracker specifications as derived from beam dynamics simulations and the results of tests prior to its installation.
Paper: MOPS020
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPS020
About: Received: 20 May 2025 — Revised: 30 May 2025 — Accepted: 30 May 2025 — Issue date: 05 Nov 2025
MOPS022
Investigation on injection-related beam loss at SuperKEKB
639
The current achieved highest luminosity at SuperKEKB is only one-tenth of the design value, and beam injection is one of the most serious issues in achieving the target luminosity. Recent operations in both the HER and LER rings have shown insufficient injection efficiencies and detector backgrounds. The achieved injection efficiency falls short of the required level, sometimes leading to difficulties in injecting the beam at high current values. Following each injection, significant signals from particle losses are detected in several Belle II detector components, particularly the vertex detector, resulting in saturating the data acquisition with a dead time exceeding 10ms. The complexity of the injection, and critical factors like injected beam quality, beam lifetime, dynamic aperture, machine errors, nonlinearity, as well as the collimation system, makes the optimization challenging. Detailed injection simulations are essential to understand the issues of the injection and guide adjustments to maximize the injection efficiency and mitigate the injection background. This paper presents the findings of HER injection simulations and their experimental validation.
Paper: MOPS022
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPS022
About: Received: 28 May 2025 — Revised: 02 Jun 2025 — Accepted: 06 Jun 2025 — Issue date: 05 Nov 2025
MOPS025
Simulation studies and design updates for the nuSTORM facility
651
The neutrinos from Stored Muons (nuSTORM) experiment aims to create neutrino beams through muon decay in a storage ring, targeting %-level precision in flux determination. With access to two neutrino flavors, it enables precise measurement of $\nu$-A cross sections and exhibits sensitivity to Beyond Standard Model (BSM) physics. With muons in the 1-6 GeV/c momentum range, it covers neutrino energy regimes relevant to experiments like DUNE and T2HK. Additionally, nuSTORM serves as a step towards a muon collider, a proof of concept for storage rings, and a testbed for beam monitoring and magnet technologies. The lattice structure consists of a pion transport line and a racetrack storage ring based on a hybrid FFA design, with conventional FODO cells in the production straight combined with FFA cells in the return straight and arcs. This paper provides an update on the nuSTORM design and simulation efforts. It covers horn and lattice optimizations for producing and storing low-energy muons, describes tracking studies of the lattice to guide event normalization and presents the latest simulated neutrino fluxes.
Paper: MOPS025
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPS025
About: Received: 28 May 2025 — Revised: 03 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
MOPS041
Status of the beam dynamics studies for the PERLE Energy Recovery Linac
702
PERLE (Powerful Energy Recovery Linac for Experiments) is a three-turn, high power Energy Recovery Linac under construction at IJCLab, France. It emerged from the design of the LHEC and FCC-eh and will serve as a hub for the validation of several technical choices and exploration of a broad range of accelerator phenomena in an unexplored operational power regime (up to 10 MW in its final version). Up to now, the final lattice design and phasing has been finalised. Current studies focus on non-linear effects and longitudinal dynamics. Also, the commissioning scheme is under developpement. We will present the status of the beam dynamics studies of the project, and highligth some of the ongoing studies
Paper: MOPS041
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPS041
About: Received: 28 May 2025 — Revised: 03 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
MOPS047
Development of new ion beams at the CERN ion injector complex for future physics programmes
718
In an effort driven by the requests from different physics experiments at CERN, the CERN ion injector complex is looking to expand its capabilities by providing lighter-than-lead ion beams. Argon and xenon were delivered for NA61/SHINE physics in 2015 and 2017, with xenon also reaching the LHC in 2017. Oxygen is foreseen to be collided in the LHC in 2025, with magnesium, boron and krypton beams also being prepared. Before new ion species can be considered operational for experiments, the feasibility of producing and accelerating these beams throughout the accelerator complex has to be assessed. This contribution presents an overview of the performance of the ion complex with recently tested magnesium ion beams, the latest results of the ongoing oxygen beam commissioning, and future plans concerning ion species that still need to be developed.
Paper: MOPS047
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPS047
About: Received: 02 Apr 2025 — Revised: 03 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
MOPS098
Statistical uncertainty studies on various data analysis methods for Stretched Wire Alignment Technology used for the Scorpius Injector
800
This paper presents statistical uncertainty studies on data analysis methods employed for the alignment of induction voltage adder (IVA) cell magnets in the Scorpius Injector. The Stretched Wire Alignment Technique (SWAT) was utilized to precisely locate and align the magnetic axis of beamline solenoid magnets. A current pulse with duration of approximately 100 µs was propagated through a stretched wire, generating a traveling wave due to the transverse magnetic force acting on the wire. The resulting transverse displacements in both horizontal and vertical directions were measured as a function of time using laser micrometers. By systematically repositioning the wire relative to the mechanical center of the magnet, the true magnetic axis and its offsets from the mechanical center were determined based on the displacement amplitudes or the magnetic field magnitudes inferred from the wire’s motion. Statistical uncertainty analysis of various data analysis methods was conducted to evaluate the reliability of the estimated magnetic axis offsets. The results provide a robust range of offset estimates, ensuring accurate alignment of the IVA cell magnets within the injector system.
Paper: MOPS098
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPS098
About: Received: 30 May 2025 — Revised: 20 Jun 2025 — Accepted: 20 Jun 2025 — Issue date: 05 Nov 2025
TUAD3
Injection into Resonance Islands
862
An Accelerator Physics Experiment (APEX) was conducted in the Relativistic Heavy Ion Collider (RHIC) to verify the formation, rotation, and size of resonance islands.The experiment provides lattice parameters to be used to facilitate an alternative method of transition crossing in the Hadron Storage Ring (HSR) of the Electron Ion Collider (EIC) project by producing a non-adiabatic kick to the off-axis beam within the island to displace the beam to the central closed orbit across transition. Proton beam was injected directly into an octupolar field driven stable resonance island in RHIC. This paper describes the procedures used to perform this Resonance Island Injection (RII) and discusses the experimental results.
Paper: TUAD3
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUAD3
About: Received: 28 May 2025 — Revised: 04 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
TUAN2
No parametric instabilities in actual linear accelerators except the envelope instability
870
Our studies indicate that parametric instabilities except the envelope instability are unlikely to be observed in actual linear accelerators unless waterbag or KV distributions are generated. Furthermore our studies and previous literatures indicate the dominance of particle resonances over parametric instabilities in high-intensity linear accelerators. Any counter evidence has not been found yet. We propose a way to overcome the previous design rule to avoid the zero-current phase advance > 90° for the high-intensity linac.
Paper: TUAN2
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUAN2
About: Received: 15 May 2025 — Revised: 05 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
TUBN1
The third long shutdown (LS3) of the CERN accelerator complex
891
TThe Large Hadron Collider (LHC) operation began in 2008. Its superconducting equipment requires a cool-down/warm-up cycle lasting several months to access some key elements such as superconducting magnets, making annual shutdowns impractical and obliged for a change in programmed stops paradigm. A new lifecycle management approach for programmed stops was therefore necessary. The large interventions were grouped and performed during long shutdowns (LSs). They include maintenance, consolidation and upgrades. LSs last about three years and are scheduled typically every six years. Since the LHC depends on its chain of preceding injectors, this approach was extended to the entire CERN accelerator complex. This paper briefly outlines the methodology used to plan, prepare and coordinate these LSs and presents the interventions and main upgrades planned for the upcoming LS3, scheduled to start mid-2026 for the LHC. The paper highlights various projects, aimed at improving safety, performance, and operational availability as well as implementing new technologies and providing new facilities for the particle physics community.
Paper: TUBN1
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUBN1
About: Received: 27 May 2025 — Revised: 02 Jun 2025 — Accepted: 13 Oct 2025 — Issue date: 05 Nov 2025
TUPB009
The latest design for a future short-baseline neutrino beamline
960
The ENUBET and NuTAG projects propose the measurements of the $\nu_e$ and the $\nu_\mu$ cross sections at the relevant energies of Hyper-Kamiokande and DUNE. While ENUBET focuses on a fully instrumented decay tunnel to achieve a precise flux measurement, NuTAG proposes the use of silicon-pixel detectors to achieve the \textit{full tagging} of the parent meson and the daughter lepton. Both ideas have merged into the Physics Beyond Colliders (PBC) Short-Baseline Neutrino (SBN) beamline study, supported through the PBC initiative at CERN. If deployed at CERN, the SBN beamline would need to be compatible with the operation of the current injector complex including the new SHiP experiment, in particular with respect to the number of protons required. The beamline's intensity requirement must therefore be kept at a minimum. With that in mind, a full optimization of the beamline was conducted to maximize the production of hadrons while fulfilling pile-up and background constraints. This contribution presents the optimized beamline design, elaborating on the techniques used and challenges faced during the design process.
Paper: TUPB009
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB009
About: Received: 23 May 2025 — Revised: 02 Jun 2025 — Accepted: 02 Jun 2025 — Issue date: 05 Nov 2025
TUPB012
Bunch filamentation within resonance islands
968
This paper presents turn-by-turn observations of internal and external filamentation within the Poincare contours of a fourth order resonance during an Accelerator Physics Experiment (APEX) in the Relativistic Heavy Ion Collider (RHIC). Beam position monitors measured the turn-by-turn evolution of the center-of-charge of the captured beam. The fraction of beam outside the island soon comes to contribute marginally to the center-of-charge signal. Simulation results are compared with experimental data.
Paper: TUPB012
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB012
About: Received: 28 May 2025 — Revised: 01 Jun 2025 — Accepted: 02 Jun 2025 — Issue date: 05 Nov 2025
TUPB013
Towards axion searches with polarized hadron beams at GSI/FAIR
972
Axions, originally introduced to solve the strong CP problem, are leading dark matter candidates appearing in various Standard Model extensions. At low masses, axion-like particle (ALP) dark matter behaves as a classical field, potentially detectable when its frequency resonates with a beam's spin-precession frequency. The JEDI collaboration's proof-of-principle experiment at COSY set upper limits on oscillating EDMs caused by ALPs, though no signals were observed. This presentation discusses COSY results and recent efforts to explore the feasibility of conducting axion search experiments using existing accelerators at GSI/FAIR with polarized hadron beams.
Paper: TUPB013
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB013
About: Received: 27 May 2025 — Revised: 30 May 2025 — Accepted: 31 May 2025 — Issue date: 05 Nov 2025
TUPB018
Towards tailored beam distributions for fixed target experiments at CERN
987
The time-of-flight (nTOF) facility at CERN uses neutrons produced by a proton beam interacting with a fixed target. To prevent target damage, an upper bound on the peak energy density has been imposed. Adhering to this constraint requires a large beam size. Similarly, at CERN’s North Area, a large beam size is required at the septa splitting the beam towards different experiments. However, both cases suffer from limitations associated to losses of the primary beam, leading to poor transmission efficiency and high radioactive activation. This paper proposes an alternative approach by manipulating the beam distribution. Given the absence of strong nonlinear elements in both transfer lines, the focus shifts to tailoring the distribution before extraction. Particle tracking simulations are presented alongside experimental results, characterizing the phase space distribution as a function of machine parameters. Advanced deep learning methods that enable efficient exploration of the parameter space are also discussed.
Paper: TUPB018
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB018
About: Received: 27 May 2025 — Revised: 30 May 2025 — Accepted: 30 May 2025 — Issue date: 05 Nov 2025
TUPB029
Simulations of beam halo distributions for a feasibility study of in-vacuum gravitational experiments at the LHC
1029
Within the realm of general relativity, the measurement of signals coming from relativistic celestial bodies have offered great insights. However, the relatively low frequency of these signals and the lack of control over their source may make the creation of well-controlled laboratory environments desirable. One possibility is to measure the relativistic beams in the Large Hadron Collider (LHC) at CERN using a milligram-scale monolithic pendulum. This would offer the possibility to test general relativity and alternative theories of gravity in an entirely new parameter regime, where the source of gravity is the almost pure kinetic energy of the ultra-relativistic particles. The low-bandwidth of the source, combined with the controllability of the setup, may offer new opportunities and insights in gravity-related research. To design the experiment, it is necessary to analyze the factors that contribute to the deterioration of the signal-to-noise ratio. One of the contributors is the impact on the pendulum of beam halo particles. This paper presents an initial assessment of the impact of beam halo on the detection of gravitational signal.
Paper: TUPB029
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB029
About: Received: 26 May 2025 — Revised: 04 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
TUPB040
Development of a comprehensive Biosafety Management System for external user experiments at NSRRC
1056
The National Synchrotron Radiation Research Cen-ter (NSRRC) operates the Taiwan Light Source (TLS) and Taiwan Photon Source (TPS) accelerators and approximately 40 end stations, about 10 of which are dedicated to biological research. Biologists from around the world utilize these facilities to investigate the structures and functions of biomolecules and cells, advancing the life sciences. Given the potential risks associated with biological experiments, particularly those involving biohazards, ongoing risk management is essential to ensure biosafety, as protocol failures often caused by human error or inadequate technique can increase the likelihood of exposure. This paper outlines the biosafety management framework at NSRRC, which supports users in sample classification, document submission, and risk identification to facili-tate a safe and efficient experimental review process.
Paper: TUPB040
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB040
About: Received: 22 May 2025 — Revised: 02 Jun 2025 — Accepted: 13 Oct 2025 — Issue date: 05 Nov 2025
TUPB055
Exploring the potential of accelerator-based neutron generators in modern research
1088
The Institute for Plasma Research in India set up an accelerator-based 14 MeV neutron generator utilizing Electron Cyclotron Resonance Ion Source technology. This advanced generator can produce 1012 neutrons per second in continuous and pulse modes. By directing deuterons at a TiT target, it generates fast neutrons that are essential for various applications such as fusion experiments, electronics testing, feasibility studies of medical isotope production, neutron radiography, etc. Various independent neutron diagnostics such as diamond detectors, proportional counters, and foil activation have been installed in the Neutron Generator. These techniques provide precise measurements of neutron flux, which are cross-checked with the associated alpha diagnostic technique to ensure accuracy. Additionally, lab-scale experiments at IPR have explored neutron irradiation for medical radioisotope production and radiation-induced damage in electronic components. This paper highlights the significance of precise measurement techniques and demonstrates the critical role of neutron generators in advancing research and practical applications, from medical isotopes to fusion neutronics studies.
Paper: TUPB055
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB055
About: Received: 26 May 2025 — Revised: 02 Jun 2025 — Accepted: 02 Jun 2025 — Issue date: 05 Nov 2025
TUPB057
Ultra-high spatial resolution in micron scale achieved by a practical cascade high energy electron radiography in HERPL
1095
As a new scheme, High Energy Electron Radiography (HEER) was considered as one of the novel mesoscale diagnostic methods for high energy density matter (HEDM) because of powerful penetration, high space-time resolution and large density dynamic diagnosis range. In this work, we R&D a practicle cascade HEER composed of a electromagnetic beamline and a permanent magnet HEER in High Energy Electron Radiography Research Platform in Lanzhou (HERPL). The field of view of the cascade HEER is about Φ3mm, and its total length is half that of the electromagnetic HEER with the same magnification. 50 MeV electron beams with picosecond pulse width bunch were used to image a TEM grid to study the spatial resolution. The excellent result was obtained with spatial resolution about 0.6 μm. In addition, electron bunch train and ultra-fast imaging acquisition system prepared for dynamic HEER were studied in this paper.
Paper: TUPB057
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB057
About: Received: 27 May 2025 — Revised: 01 Jun 2025 — Accepted: 03 Jun 2025 — Issue date: 05 Nov 2025
TUPB068
Density measurements and simulations on confined electron column in GL2000 Gabor-lens device
1120
GL2000 Gabor-lens (GL) is a 2m long device built mainly for focusing and space charge compensation of hadron beams in energy ranges up to GeV. The electron cloud is initially produced by cold-cathode method with gradually ionisation of residual gas and is confined in a cylindrical trap much longer compared to previous constructed lenses. Density measurements were carried out at the test-stand in Goethe University in 2024. Outgoing stream of residual gas ions was detected within cylindrical spectrometer mounted on axis outside of the lens. Due to the dependency of the kinetic energy on starting potential, the on-axis potential and therefore confined average charge density can be derived. Measured densities were evaluated in a range of $10^{14}$-$10^{15} m^{-3}$. A large scale multi-particles Monte-Carlo-PIC (particle-in-cell) simulations with electrons and ions were carried out to understand collective phenomena in non-neutral plasma and to use the latter for linear and non-linear beam manipulation. Measurements and simulation results will be presented.
Paper: TUPB068
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB068
About: Received: 28 May 2025 — Revised: 13 Oct 2025 — Accepted: 13 Oct 2025 — Issue date: 05 Nov 2025
TUPB074
Status of J-PARC accelerator chain
1128
The Japan Proton Accelerator Research Complex supplies a high-intensity proton beams for the physics experimental programs in the Material and Life Science Facility (MLF), the Hadron experimental facility and the neutrino target. In such a high-intensity hadron accelerator, losing less than 0.1% of the beam can cause several problems. Such lost protons can cause serious radioactivation and accelerator component malfunctions. Therefore, we have been continuing a beam study to achieve high-power operation with enough smaller loss condition. In addition, we have also improved and maintained the accelerator components, enabling a stable operation. Through these efforts, we established a beam power of 1-MW operation for the MLF users and a beam power of 800-kW operation for the neutrino users. In this paper, Recent achievement is summarized.
Paper: TUPB074
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB074
About: Received: 29 May 2025 — Revised: 13 Oct 2025 — Accepted: 13 Oct 2025 — Issue date: 05 Nov 2025
TUPM027
The future of the CLEAR facility: consolidation, ongoing upgrades and its evolution towards future electron facilities at CERN
1220
The CERN Linear Accelerator for Research (CLEAR) is a versatile 200 MeV electron linac followed by an experimental beam-line, operated at CERN as a user facility. Its user community includes research groups working on beam instrumentation R&D, advanced acceleration techniques and irradiation studies, including medical applications. A recent internal review has confirmed the excellence of its scientific output and its strategic interest for the laboratory, extending the facility operation until at least 2030. In this paper we discuss the consolidation actions needed for continued operation together with the ongoing hardware improvements and their impact on the future experimental program. These upgrades include a new front-end for the laser system allowing for a highly flexible time structure, better stability and higher repetition rates, plus the implementation of a second beam line whose optics has been designed to match user requirements and will provide additional testing capability. Finally, we discuss the potential role of CLEAR in the path towards future high-energy electron facilities at CERN.
Paper: TUPM027
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPM027
About: Received: 28 May 2025 — Revised: 04 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
TUPM036
Feasibility study of a THz beamline design for the THz user facility at NSRRC
1243
Feasibility design of THz beamlines for the use of the superradiant THz free electron laser driven by the NSRRC high brightness photo-injector has been studied. The Accelerator Test Area (ATA) building, where the photo-injector installed, will be transformed into a THz user facility that meets radiation safety regulations. Narrow-band intense superradiant THz radiations with pulse energy as high as 20 μJ and tunable central frequency from 0.6 to 1.4 THz, generated by injecting an ultrashort electron beam into a U100 planar undulator, can be a useful tool for nonlinear and time-resolved pump-probe experiments. There will be two stages for user experiments. Phase I will be opened for users with the experimental station installed right after the THz sources in the accelerator tunnel. Another THz beamline, which is currently being designed to maintain the quality of THz radiations after propagation over longer distances, will be built for user experiments in Phase II. This report briefly describes the beamline design and the operation of user experiments in Phase I.
Paper: TUPM036
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPM036
About: Received: 27 May 2025 — Revised: 29 May 2025 — Accepted: 01 Jun 2025 — Issue date: 05 Nov 2025
TUPM040
Molecular beam epitaxial growth of Sodium Antimonide photocathodes
1246
Cornell University has been working on developing techniques to grow single crystal photocathodes for electron sources using the Molecular Beam Epitaxy (MBE) technique. As a result, the first single crystal Cs3Sb photocathode was produced, which has shown high quantum efficiency and is expected to have a low Mean Transverse Energy (MTE). Now, other alkali materials are being explored. In this work, we report the epitaxial growth of Na-Sb photocathodes at the PHOtocathode Epitaxy Beam Experiments (PHOEBE) laboratory at Cornell University, employing a sequence of shuttered growth steps to form distinct unit cells. The photocathodes were characterized by Quantum Efficiency (QE) measurements and Reflection High-Energy Electron Diffraction (RHEED) patterns collected during growth. The RHEED streaky pattern shows angle dependence, confirming their single crystal structure. Notably, these Na-Sb photocathodes exhibited a QE exceeding 1% at 400 nm, which is much higher than previous reports on this compound. The possible reasons for this discrepancy are discussed.
Paper: TUPM040
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPM040
About: Received: 29 May 2025 — Revised: 03 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
TUPM070
Progress of SUNDAE2 magnetic measurement setup for superconducting undulators at European XFEL
1319
At European XFEL up to six superconducting undulators with 18 mm period and 1.83 T magnetic field are planned to enlarge the hard X-ray photon range above 30 keV. Currently, S-PRESSO, a prototype with 2x 2m long undulator sections plus phase shifter in a 5m long cryostat is being produced. The SUNDAE2 (Superconducting UNDulAtor Experiment 2) magnetic field test facility aims to perform in-vacuum magnetic field measurements of superconducting undulators (SCUs). This work provides an update on the progress of SUNDAE2, which employs Hall probe, moving wire, and pulsed wire techniques for precise magnetic field characterization to meet the specifications for the FEL operation.
Paper: TUPM070
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPM070
About: Received: 28 May 2025 — Revised: 04 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
TUPM079
A report from ISBA24 (The 7th international school on beam dynamics and accelerator technology) in Chiang Mai, Thailand
1341
ISBA24 (The 7th International School of Beam Dynamics and Accelerator Technology) was held in Chiang Mai, Thailand, jointly hosted by Chiang Mai University, Hub of Talents in Particle Accelerators (operated by the Thailand Center of Excellence in Physics), Synchrotron Light Research Institute (Public Organization) and Hiroshima University. ISBA is a series of international accelerator schools initiated in 2018 at Hiroshima, Japan promoted by IINAS(IINAS-NX). ISBA24 was held from November 1 to 9, 2024. The school brought together over 80 participants, including 18 professors and experts, and 64 students from ASEAN countries and beyond. All participants enjoyed intense lectures, practical exercises, student presentations, and social events such as excursions and Thai northern style banquet. An overview of ISBA24 will be presented and human resource development in accelerator science will be discussed.
Paper: TUPM079
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPM079
About: Received: 28 May 2025 — Revised: 29 May 2025 — Accepted: 30 May 2025 — Issue date: 05 Nov 2025
TUPM086
Simulation study of beam-driven plasma wakefield experiments on CLARA
1353
The Compact Linear Accelerator for Research and Applications (CLARA) is an electron test facility capable of delivering tunable 250 MeV electron beams with up to 250 pC charge to the Full Energy Beam Exploitation (FEBE) experimental area . In this study, we investigate the feasibility of conducting beam-driven plasma wakefield acceleration (PWFA) experiments using the CLARA beam and experimental area. We present simulations of various potential experiments, considering the baseline and R&D beam parameters expected to be delivered to the FEBE experimental chambers*. Our findings highlight the potential for CLARA to support advanced PWFA research, with detailed analysis of beam dynamics and experimental configurations.
Paper: TUPM086
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPM086
About: Received: 28 May 2025 — Revised: 04 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
TUPS017
Study on Ion Bunch Generation Using a Laser Plasma RF Ion Source
1446
The development of high-intensity, high-quality ion sources is essential for advanced applications such as particle beam therapy and nuclear physics experiments. The aim of this study is to integrate the Laser Plasma RF Ion Source (LaPRIS), currently under development, into the cyclotron at the Research Centre for Nuclear Physics (RCNP) in order to accelerate ion bunches with high precision and intensity for advanced applications. LaPRIS can generate laser-plasma in an RF field at the laser focus spot and produce bunches at arbitrary timings. Previous research* has achieved a proton beam with a peak current of 1.2 mA and a bunch width of 5 ns. This allows the charge per bunch to be increased by a factor of 100 compared to conventional systems. This makes it possible to track the beam behavior for each bunch, which has potential applications in high-intensity cyclotron research. The injection into the cyclotron must be matched to the acceptance, so the emittance of the beam bunches is measured under different laser characteristics and target conditions to investigate the beam properties.
Paper: TUPS017
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPS017
About: Received: 02 Jun 2025 — Revised: 04 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
TUPS020
Hands on training with ASTRA at ISBA'24
1458
As part of the program of the seventh International School on Beam Dynamics and Accelerators (ISBA'24), we carried out hands-on training with the accelerator simulation code ASTRA. A selection of students used the intensive two-hour daily course to go from learning the basics of ASTRA to designing and optimizing their own accelerators. Here we report the details of training, the student projects and their presentations to their instructors and peers, and plans for future hands-on training programs.
Paper: TUPS020
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPS020
About: Received: 27 May 2025 — Revised: 30 May 2025 — Accepted: 30 May 2025 — Issue date: 05 Nov 2025
TUPS031
Electrostatic deflector Nuclotron modernization for EDM experiment
1487
Considered the current Nuclotron structure for precision EDM-experiments as an independent synchrotron storage ring equipped with electrostatic deflectors. In this regard, the design must ensure the preservation and precise regulation of spin dynamics stability. Moreover, the initial purpose of the structure as a booster of polarized beams in the collider has been preserved.
Paper: TUPS031
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPS031
About: Received: 28 May 2025 — Revised: 05 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
TUPS033
Quasi-frozen spin concept to search for the electric dipole moment of the proton and deuteron
1494
One of the possible proofs of CP violation beyond the Standard Model may be the discovery of permanent Electric Dipole Moments (EDM) of elementary particles. To search for the EDM of charged particles, the Frozen Spin (FS) concept was first proposed at BNL. The implementation of the latter involves the creation of a special storage ring in which the spin vector is preserved along the momentum and precesses due to the EDM only. In a magnetic storage ring initially not dedicated to measure the EDM, it is also possible to study the EDM by inserting electrostatic or E+B elements that compensate for the spin rotation in the bending magnets in a so-called Quasi-Frozen Spin (QFS) mode. Magneto-optical structures fulfilling the QFS condition can be used in application to study the proton and deuteron EDM and for axion search at the NICA accelerator complex. The main features of the implementation of the QFS concept are discussed, the method of measuring the EDM in the frequency domain, as well as the main spin dynamics properties of the lattice are covered.
Paper: TUPS033
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPS033
About: Received: 07 May 2025 — Revised: 30 May 2025 — Accepted: 31 May 2025 — Issue date: 05 Nov 2025
TUPS035
TURBO – Enabling fast energy switching for hadron therapy with constant magnetic fields
1498
The energy layer switching time is a limiting factor for hadron therapy, precluding fast beam delivery and reducing treatment efficacy. For rapid energy switching the beam delivery system must be achromatic with zero dispersion over a large energy range. At the University of Melbourne, the TURBO project will utilise Fixed Field Accelerator techniques to demonstrate transport of a ±42% momentum spread beam around a 30° bend, with constant magnetic fields to eliminate the energy switching bottleneck. This will be demonstrated with an electrostatic Pelletron accelerator. A fast-switching energy degrader with thin diamond films has been designed to quickly change proton beam energies in the range 0.5-3.0MeV, covering the full clinical range when scaled up. A new design technique using nonlinear magnetic fields for energy-dependent focusing has been developed to minimise delivered beam variations. A novel method has been found to produce nonlinear permanent magnet arrays without custom magnets, enabling fast prototyping and reuse of magnets. With these innovations, the TURBO project will demonstrate rapid energy switching for hadron therapy to enable improvements in patient outcomes.
Paper: TUPS035
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPS035
About: Received: 28 May 2025 — Revised: 03 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
TUPS063
NLCTA and the X-band Test Area at SLAC
1574
The Next Linear Collider Test Accelerator (NLCTA) facility at SLAC National Accelerator Laboratory provides unique capabilities for conducting accelerator research and testing technology with accelerator applications, as well as beam time for experiments using the X-band Test Accelerator (XTA). Test areas in the facility support high power RF testing over a range of frequencies and operating temperatures, allowing for a broad range of ongoing research programs. Experiments include irradiation studies, high gradient accelerator testing, superconducting materials testing, detector testing, prototype development for medical applications like proton therapy for cancer treatment, and electron beam diagnostics using THz streaking. This variety in research topics takes advantage of the NLCTA's flexible infrastructure and wide range of in-house expertise. Facility capabilities and highlights from the active experimental program are presented here.
Paper: TUPS063
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPS063
About: Received: 28 May 2025 — Revised: 02 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
WEPB034
Beam impact experiment to qualify the damage limits of Nb3Sn sample coils pre-irradiated to 30 MGy
1807
A series of experiments has been carried out at CERN to derive the damage limits of superconductor strands and sample coils. The latest experiment was designed to characterize the limits of Nb3Sn racetrack sample coils impacted by a 440 GeV/c proton beam at cryogenic temperature. The effect of a beam impact on superconducting coils aged by long-term radiation exposure, however, is currently unknown. This paper outlines the preparation of an experiment to be performed at the HiRadMat facility to investigate the damage on coils which have been aged with X-rays to simulate the anticipated integral dose levels reached by the HL-LHC final focusing magnets during their operational lifetime, of 25 to 30 MGy. The damage limits for these coils will be derived and compared with the results previously obtained for non-aged coils. The design and fabrication of these sample coils, the details of the X-ray irradiation and the results from their qualification tests before beam impact is discussed. The results of energy deposition simulations that define the optimal parameters for the proton beam to be used are presented. The experimental setup and procedure are discussed.
Paper: WEPB034
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPB034
About: Received: 28 May 2025 — Revised: 03 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
WEPB037
Faint magnetic field shield using the Meissner effect
1818
Magnetic fields play an important role in many physics studies, and many measurement items in physics experiments require control of micro magnetic fields. Although superconducting accelerating cavities can generate high electric fields at low power, the material niobium is a type-II superconductor, and trapping the ambient magnetic flux during the superconducting transition increases the operational losses. For this reason, micro magnetic shielding is important, and strengthening micro magnetic shielding is essential when aiming for further power saving. Therefore, we have begun to study the shielding effect of micro magnetic fields based on the Meissner effect of superconductors, which are perfectly antimagnetic. We have selected AMR (Anisotropic-Magneto-Resistive) type 3-axis sensors, drive five 3-axis sensors under cryogenic temperature, and bring their signals to the room temperature side with nine cables, including the power supply, by multiplexing. The signals were calibrated with the output of the FluxGate under cryogenic conditions. Preliminary results show that the amount of flux rejection is generally monotonically increasing with temperature gradient.
Paper: WEPB037
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPB037
About: Received: 02 Jun 2025 — Revised: 03 Jun 2025 — Accepted: 03 Jun 2025 — Issue date: 05 Nov 2025
WEPB042
Third order resonance correction using new Trim-S system in J-PARC MR
1826
In the Japan Proton Accelerator Research Complex (J-PARC) Main Ring (MR), to address the issue of resonance correction for third-order resonances in both on- and off-momentum particles, an upgrade project utilizing 24 Trim-S units has been proposed based on numerical simulations. As a first step in verifying its effectiveness, four additional Trim-S (new Trim-S) power supplies, configured with a System-on-Chip (SoC) Field Programmable Gate Array (FPGA) controller, have been installed. The performance of the new system was experimentally verified by correcting the resonance using these 4 new Trim-S units. Beam loss was successfully reduced compared to that with the original Trim-S system, demonstrating the effectiveness of the new system.
Paper: WEPB042
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPB042
About: Received: 14 Apr 2025 — Revised: 31 May 2025 — Accepted: 02 Jun 2025 — Issue date: 05 Nov 2025
WEPB043
A study on the pattern waveform high-voltage power supply for the rapid cycling induction synchrotron
1830
The application of a 10 Hz repetitive induction synchrotron (IS) to the next generation of heavy ion therapy drivers is under investigation* **. The IS is characterized by the use of a pulse voltage to accelerate the beam, but until now, due to technical limitations, the magnitude of the pulse voltage could not be perfectly matched to the acceleration conditions. Instead, a pulse density modulation method has been adopted. However, this method inevitably induces synchro-beta coupling, which increases beam emittance. To overcome this problem, we develop a pattern-voltage dc power supply in which the output voltage waveform has a sinusoidal half-wave shape that matches the acceleration conditions. First, a mini-model was fabricated, and comparative experiments were conducted with three different circuit schemes: (A) a bipolar-controlled full-bridge circuit, (B) a unipolar-controlled full-bridge circuit, and (C) a series connected half-bridge circuit. This paper describes the results of these tests and issues for future study.
Paper: WEPB043
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPB043
About: Received: 28 May 2025 — Revised: 02 Jun 2025 — Accepted: 02 Jun 2025 — Issue date: 05 Nov 2025
WEPB062
Development of a compact high voltage pulse power supply of MARX-type for muon linac klystron
1884
We have been developing a compact pulse power supply with output pulse waveform specifications of 75kV/40A/50us/25Hz. This power supply is used to drive klystron for muon linac, which requires high stability and reliability. Next-generation power semiconductor SiC-MOSFETs with excellent characteristics of ultra-high breakdown voltage and low loss at 13kV, which were realized through the technological development of wide bandgap semiconductor devices, are used. Combining this SiC-MOSFET with the MARX circuit will realize a more compact pulse power supply with lower loss than conventional ones. In addition, it can be applied to portable accelerators in the future. In this presentation, the circuit design of the MARX power supply will be reported.
Paper: WEPB062
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPB062
About: Received: 28 May 2025 — Revised: 02 Jun 2025 — Accepted: 03 Jun 2025 — Issue date: 05 Nov 2025
WEPB083
The cavity combiner development for TPS SSPA tower at NSRRC
1912
NSRRC builds four home-made solid state power amplifier towers to provide 300 kW for one superconducting RF cavity at TPS. The power combining tree of one tower is two-stages structure with a complex wire connection. In order to simplify the wire connection and increase the power combining efficiency, we devote resources to develop the cavity combiner. In this study, a 21-ports cavity combiner is designed and manufactured. The RF properties, S11 and S21, of output port were simulated and measured to evaluate the combining efficiency.
Paper: WEPB083
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPB083
About: Received: 29 May 2025 — Revised: 02 Jun 2025 — Accepted: 02 Jun 2025 — Issue date: 05 Nov 2025
WEPM018
Optimizing beam-beam beta-beating for luminosity enhancement at the LHC
1992
The optimization of LHC operation is focused on achieving the highest possible integrated luminosity to maximize experimental data collection. Given the limitations of current detector systems, maintaining a constant level of integrated luminosity has become more critical than achieving a high peak luminosity. Techniques such as beta-leveling and separation levelling have already been implemented to adjust luminosity and enhance operational efficiency. This study describes how the beam-beam beta-beating effects propagating between the multiple experimental interaction points can serve as an additional mechanism to further increase the total integrated luminosity. The operational solutions and impact on performance will be shown for both the current LHC and its future High Luminosity upgrade.
Paper: WEPM018
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPM018
About: Received: 23 May 2025 — Revised: 05 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
WEPM020
Towards Improving luminosity using optics tuning and data-driven methods
2000
The results of Run 24 experiments at Relativistic Heavy Ion Collider (RHIC) for improving luminosity using optics tuning are presented in this study. In the first experiment, MADx matching was used to output magnet strengths corresponding to specific s star movements around Interaction Region 8 (IR8). The corresponding Zero Degree Calorimeter (ZDC) signal was measured in place of luminosity, and Bayesian Optimization aids search of optimal movements. It was found that values retrieved from matching were inaccurate, resulting in negative feedback loops. The second experiment focused on calculating accurate s star movements. The matching method was replaced with a linear sensitivity matrix, directly relating optics to power supply, and its null space was used to fit constraints such as hysteresis effects. At the experiment, beam losses were observed at collimators around boundary of IR8, which were fixed for the third experiment. Dynamic mode decomposition was also introduced to improve quality of turn-by-turn (TBT) data as well as accuracy and consistency of optics measurements at IR8. These improvements will be tested in the experiment of next RHIC run for luminosity optimization.
Paper: WEPM020
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPM020
About: Received: 28 May 2025 — Revised: 01 Jun 2025 — Accepted: 02 Jun 2025 — Issue date: 05 Nov 2025
WEPM029
Trajectory design for passing through solenoid magnet fringe field and method for adjusting its strongly X-Y coupled phase space for three-dimensional spiral beam injection
2020
A three-dimensional spiral beam injection scheme* has been developed to realize very precise measurement of the muon spin precession frequency in the level of sub-ppm. A 300MeV/c muon beam is injected into a precisely adjusted storage magnet of sub-ppm uniformity by applying medical MRI magnet technologies for J-PARC muon g-2/EDM experiment. A strongly X-Y coupled beam is required to deliver beam into the storage volume via strong radial fringe field volume of solenoid magnet followed by beam injection channel through iron yoke**. A dedicated design work of reference trajectory and beam phase space has been made in this injection section. In this presentation, we show evaluated the tolerance for the accuracy of the reference trajectory and the orbital position dependence of the required X-Y coupling parameters and discuss the required accuracy of the transport line placed upstream of the beam-line which includes eight rotating quadrupoles on the 10m of beam transport line**. Additionally, a pair of dedicated magnets called active shield steering magnet will be set at the entrance and the exit of the beam channel to perform orbital correction of the reference trajectory.
Paper: WEPM029
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPM029
About: Received: 28 May 2025 — Revised: 04 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
WEPM034
Beam optics model and characterization for CERN's low-energy ISOLDE transfer lines
2040
The PUMA (antiProton Unstable Matter Annihilation) experiment at CERN aims to explore the interaction of antimatter with exotic isotopes, utilizing the unique capabilities of CERN’s ISOLDE facility and Antiproton Decelerator. This contribution presents recent advancements in the beam transfer lines optics studies relevant to the success of the experiment, and to ISOLDE’s operation in general. A detailed beamline model has been developed using MAD-X and XSUITE, including the consideration of apertures and alignment errors. Quadrupole scans and kick response measurements have been employed to build and benchmark the model. In addition, tomographic reconstruction was tested, aiming to obtain a detailed characterisation of the beam's transverse phase space. A distinctive feature of ISOLDE’s beamlines is the use of electrostatic, rather than magnetic, quadrupoles. To address this, an electrostatic quadrupole model was developed and benchmarked using CST. These promising results validate the optics model, demonstrating its potential to improve beam delivery across the Low-Energy ISOLDE facility and contributing towards the PUMA experiment's operational readiness.
Paper: WEPM034
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPM034
About: Received: 26 May 2025 — Revised: 31 May 2025 — Accepted: 02 Jun 2025 — Issue date: 05 Nov 2025
WEPM055
Design of beam phase space distribution to realize precise three-dimensional beam injection at J-PARC muon g-2/EDM experiment
2101
In the J-PARC muon g-2/EDM experiment, a three-dimensional beam injection scheme will be adopted to inject a 300 MeV/c muon beam into a compact storage orbit. In this scheme, a low-emittance muon beam with X-Y coupling is injected from the edge of a solenoidal magnet and guided to a compact beam storage region where the magnetic field is precisely tunned for a muon g-2 measurement with a good systematic uncertainty. The method to design the injected beam phase space distribution was previously unclear, as muons pass through an area with a largely position-dependent, non-linear, and time-dependent magnetic field created by the solenoidal fringe field and kicker field during the injection process. This presentation introduces a new design method. By utilizing a linear approximation of beam transportation, an acceptance is defined for the injected beam distribution. This acceptance is represented as a three-dimensional hyperplane, allowing for a search of an optimal beam distribution by comparing it to beam phase space distribution candidates. The presentation reports the procedure and results of this method, as well as its limitations due to the assumed linear approximation.
Paper: WEPM055
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPM055
About: Received: 28 May 2025 — Revised: 02 Jun 2025 — Accepted: 03 Jun 2025 — Issue date: 05 Nov 2025
WEPS022
Progress on experimental efforts to investigate CSR shielding effects
2290
A collaboration is underway to investigate the impact of CSR and shielding on the beam of various shapes as it passes through a chicane. Experimental efforts are being made at the Argonne Wakefield Accelerator (AWA) facility. Currently, the facility is equipped with two identical doglegs with reversing quadrupoles that allow doglegs to function as a chicane, and manually adjustable shielding gaps in dipole magnet chambers. A 6.4-ps-long flattop laser pulse is generated using alpha-BBO crystals, and linac phase is adjusted to either preserve the bunch length or slightly compress it through the chicane. While the expected beam behavior was observed during the initial experiment, the current chicane’s exceptionally large R56 (=0.45 m) rendered it sensitive to modulations from the alpha-BBO configuration. We have confirmed a new beam-based tuning procedure for BBO crystals at the AWA facility and its effect on modulations. We present the summary of experimental efforts to date and outline future plans.
Paper: WEPS022
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPS022
About: Received: 28 May 2025 — Revised: 30 May 2025 — Accepted: 31 May 2025 — Issue date: 05 Nov 2025
WEPS036
First proton crabbing at the LHC via head-on beam-beam interaction
2317
The first experimental observation of a 10 $\mu$m crabbing orbit at 1~$\sigma_z$ induced by head-on collisions with a non-zero crossing angle ($\theta_c$) in a high-energy proton beam at the LHC is presented. This challenging measurement required both the design of a dedicated experiment and a careful calibration and optimization of the beam instrumentation to produce and detect such a subtle effect. By varying the crossing angle from positive to negative values the reversibility of the effect and its dependence on the crossing angle were also demonstrated. Lattice simulations were performed to corroborate the experimental results, showing excellent agreement with the measured crabbing amplitudes. This experiment highlights the potential of the existing wideband beam-position monitors to diagnose crabbing effects, which will be crucial in the HL-LHC upgrade.
Paper: WEPS036
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPS036
About: Received: 19 May 2025 — Revised: 02 Jun 2025 — Accepted: 03 Jun 2025 — Issue date: 05 Nov 2025
WEPS039
Progress & developments of beam delivery simulation (BDSIM)
2325
BDSIM (Beam Delivery Simulation) is a Monte Carlo particle tracking tool for accelerator beamline modelling. It integrates particle transport with detailed geometry and physics using Geant4 for precise modelling of particle-matter interactions in 3D models of particle accelerators. Primarily for energy deposition studies and beam loss simulations, BDSIM allows a high degree of control and customisation, and is ideal for understanding and enhancing the performance of beamline designs. BDSIM has numerous modelling applications, including high-energy physics facilities, particle detection experiments, synchrotron light sources, medical accelerators, and novel acceleration experiments. Here, we present recent developments of BDSIM. This includes improved custom inverse-Compton scattering processes for laserwire and polarimeter simulations and extending the process to model polarization & electron spin; improved acceleration including transverse focussing in RF elements with implementation of 3D transverse magnetic and electric modes; custom elements for modelling muon cooling channels; and updates to interfacing with Xsuite via improved code couplings and BDSIM distribution methods.
Paper: WEPS039
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPS039
About: Received: 28 May 2025 — Revised: 01 Jun 2025 — Accepted: 02 Jun 2025 — Issue date: 05 Nov 2025
WEPS045
Investigating the Impact of alternative LHC optics on accelerator backgrounds at FASER using BDSIM
2341
Alternative configurations around the ATLAS experiment are investigated aiming to reduce muon rates at forward physics experiments such as FASER and SND@LHC. The Geant4 toolkit BDSIM is used to propagate muons through a model of a section of the LHC and the TI12 tunnel, where the FASER experiment is located. We compare the muon rates in BDSIM with FASER data collected during dedicated tests in the LHC. Results show a significant worsening of the background with the non-nominal polarity configuration of the triplet quadrupoles, used in 2024. The horizontal crossing angle further increased the background, however a partial mitigation of approximately 10% was found using a set of orbit corrector magnets. Additionally, nominal triplet polarity was favorable for both vertical and horizontal crossing angles. This work served as benchmark of simulations that will be used to validate future configurations.
Paper: WEPS045
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPS045
About: Received: 28 May 2025 — Revised: 05 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
WEPS132
Estimation of the required current on the anode power supply for high power operation in the J-PARC Main Ring
2443
The J-PARC Main Ring (MR) RF system has been undergoing upgrades in preparation for the Hyper-Kamiokande (Hyper-K) neutrino experiment, which is scheduled to begin receiving a 1.3 MW proton beam in 2028. The beam will be accelerated from 3 GeV to 30 GeV within the MR over a reduced cycle time of 0.58 seconds, down from the current 0.65 seconds. Additionally, the number of protons will be increased from $2.3 \times 10^{14}$ to $3.1 \times 10^{14}$to support high power operation. To accommodate these enhancements, additional RF cavities equipped with 600 kW vacuum tubes will be installed, and the anode current will be increased accordingly. Maintaining a constant RF voltage under these conditions requires more anode current to supply the necessary voltage and to compensate for beam loading effects. This paper presents an estimation of the anode current required for high-power beam operation.
Paper: WEPS132
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPS132
About: Received: 28 May 2025 — Revised: 01 Jun 2025 — Accepted: 02 Jun 2025 — Issue date: 05 Nov 2025
THYD1
Reinforcement learning in particle accelerators
2481
Reinforcement learning (RL) is a unique learning paradigm inspired by the behaviour of animals and humans to learn to solve tasks autonomously. Learning occurs through interactions with an environment, exploring, and evaluating strategies under various conditions. RL excels in complex environments, can handle delayed consequences, and is able to learn solely from experience without access to an explicit model of the system. This makes RL particularly promising for particle accelerators, where the dynamic conditions of particle beams and accelerator systems require continuous adaptation, and modelling is challenging. Although RL applications are emerging in accelerator physics and showing promising results, their widespread introduction faces critical challenges. Among the main obstacles are the effective formulation of control problems, training, and the deployment of solutions in real systems. This paper provides an overview of the potential of RL in accelerator applications, highlighting current challenges and future research directions.
Paper: THYD1
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THYD1
About: Received: 27 May 2025 — Revised: 30 May 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
THYN1
Deceleration of ion beams - Related challenges and opportunities
2487
The GSI facilities of CRYRING and HiTRAP are used for decelerating ion beams to low energies. This deceleration phase is preceded by the generation and acceleration of those ions. CRYRING and HiTRAP operate at the junction between accelerator science and atomic physics. The scientfic motivation, the operation principle, the state of the art and future outlooks are presented.
Paper: THYN1
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THYN1
About: Received: 30 May 2025 — Revised: 03 Jun 2025 — Accepted: 03 Jun 2025 — Issue date: 05 Nov 2025
THBN2
FAIR commissioning - Towards first science
2495
The international Facility for Antiproton and Ion Research (FAIR) is under construction at the GSI Helmholtz Centre in Darmstadt. The first project stage includes the superconducting 100 Tm heavy-ion synchrotron SIS100, the Super Fragment Separator, and associated beam transport lines. Part of GSI’s existing accelerator chain, comprising UNILAC and SIS18, will serve as injector. Installation work in the FAIR accelerator tunnels and supply buildings has been ongoing since early 2024. As progress continues, special attention is now on the start of commissioning, beginning in 2025 with the cryogenic plant. Commissioning of the transport line will follow at the end of 2025, and beam commissioning is scheduled for the second half of 2027. This paper outlines the current status of the project, commissioning strategy and timeline.
Paper: THBN2
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THBN2
About: Received: 24 May 2025 — Revised: 30 May 2025 — Accepted: 02 Jun 2025 — Issue date: 05 Nov 2025
THPB013
The wire alignment method in a magnetic field measurement system
2526
In the magnetic field measurement system, a single-core CuZr wire is used in both the stretched-wire (SW) and pulsed wire measurement (PWM) systems. Before measuring the magnetic field of the undulators, the CuZr wire must be aligned with the center of the undulator mechanism. The SW system is then employed to locate the magnetic field center of the undulator. The traditional method involves using a theodolite and level to align the CuZr wire with the center of the undulator mechanism. However, for cryogenic permanent magnet undulators (CPMUs), superconducting magnets, or any magnets installed in a vacuum chamber, aligning the CuZr wire with the center of the mechanism using traditional methods presents challenges. In this paper, we propose a method that utilizes the wire's contact with the magnet to observe changes in resistance for positioning purposes, thereby overcoming the limitations of center alignment in chamber-surrounded undulator mechanisms.
Paper: THPB013
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPB013
About: Received: 22 May 2025 — Revised: 02 Jun 2025 — Accepted: 13 Oct 2025 — Issue date: 05 Nov 2025
THPB014
A vibrating wire system for multipole magnets alignment in TPS
2529
An auto-scanning vibrating wire system for magnets centering alignment was developed at NSRRC. It is prepared for the replacement of magnets on the girder of TPS storage ring in case of malfunction and also as a pre-study topic of the TPS upgrade. With this system, both quadrupole and sextupole magnets were tested in the laboratory. This paper presents the system configuration and testing results.
Paper: THPB014
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPB014
About: Received: 29 May 2025 — Revised: 03 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
THPB023
Numerical simulation of a modified air conditioning system of the experimental hall at TPS
2552
Taiwan Photon Source (TPS) has been committed to serve users for eight years. In the first and second phases of TPS beamline project, there were 16 beamlines had been in operation. The third phase project had been launched in 2021. Facing the more persons and equip-ment in the experimental hall as well as power saving issue, we applied the computational fluid dynamic (CFD) scheme to simulate the air conditioning system to obtain better cooling efficiency. We modelled one twelfth of the TPS experimental hall and two beamlines.
Paper: THPB023
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPB023
About: Received: 28 May 2025 — Revised: 30 May 2025 — Accepted: 13 Oct 2025 — Issue date: 05 Nov 2025
THPB031
Experimental studies of thermal contact conductance between copper, stainless steel and aluminum samples using a setup developed at ALBA Synchrotron Light Source
2580
Accurate knowledge of the Thermal Contact Conductance (TCC) between surfaces is of great importance for the design of components in particle accelerators, such as mirrors, monochromators, filters, detectors, among others. The TCC depends on many variables such as surface finish, type of material, pressure between samples, temperature and interface materials. The TCC can be found in specialized literature, but it is not always possible to find this information for all applications. This forces the design engineer to assume conservative or optimistic values that can result in over or under sized designs. In this context, an experimental setup has been developed in the Engineering Division of ALBA to evaluate thermal contacts under ambient and cryogenics conditions, in vacuum and for different pressure ranges between samples. This work presents the latest experimental results obtained for sample combinations of Copper, Stainless Steel and Aluminium materials.
Paper: THPB031
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPB031
About: Received: 23 May 2025 — Revised: 14 Oct 2025 — Accepted: 14 Oct 2025 — Issue date: 05 Nov 2025
THPB035
Upgrading the IMPACT application for enhanced risk declaration and approval processes at CERN
2587
The declaration and approval of activities related to CERN's accelerator complex are critical for ensuring safety and compliance. For the past 12 years, the Intervention Management Planning And Coordination Tool (IMPACT) has been the primary system facilitating these processes, enabling approvals by domain and location experts. However, evolving requirements and advancements in technology have necessitated a significant upgrade. This paper introduces the new system, which represents a migration from the legacy IMPACT application. It preserves historical data while offering key improvements in usability, especially for mobile platforms. The updated system simplifies user interactions with clearer workflows and interfaces, reducing complexity for those declaring or approving activities. The development process prioritized a user-centric approach, incorporating iterative testing with stakeholders to ensure the system meets the operational needs of CERN's diverse activities. This paper outlines the technical architecture of the new system, strategies for data migration, and mechanisms designed to improve safety communication. This initiative aligns IMPACT with the integrated engineering platform developed by the Engineering department and contributes to CERN’s overarching goal of advancing safety standards through robust digital solutions.
Paper: THPB035
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPB035
About: Received: 19 May 2025 — Revised: 04 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
THPB059
A helium-cooled target design for the SPS Beam Dump Facility (BDF) at CERN
2634
CERN’s upcoming SPS Beam Dump Facility (BDF) will host a production target designed to manage challenging thermal and mechanical conditions while providing the physics output required by the Search for Hidden Particles (SHiP) experiment. It must fully absorb 400 GeV/c protons and dissipate up to 305 kW. The baseline design consists of water-cooled tantalum-alloy clad TZM and tungsten (W) blocks. Challenges for the maintenance and reliability of the baseline design led to the development of alternative concepts. The leading design—a helium-cooled W target—optimizes thermal management and structural integrity while simplifying the manufacturing and improving its physics performance for the SHiP experiment. The experimental validation of this concept will be via testing multiple prototypes in an existing slow beam extraction test bench at CERN’s North Area. In parallel, extensive R&D is being pursued on: properties of pure W products including hot-rolled plates; manufacturing of seamless blocks; W-W diffusion bonding techniques. This contribution includes an overview of the helium-cooled target design and a summary of the ongoing material characterization, prototyping and beam-tests.
Paper: THPB059
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPB059
About: Received: 28 May 2025 — Revised: 05 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
THPB079
Investigation of properties of CuZr alloy for vacuum chamber structural materials
2644
CuZr alloy is considered for the structural material of the vacuum chamber of the Hefei Advanced Light Facility (HALF) storage ring. We tested the outgassing rate of CuZr material. The outgassing rate of CuZr alloy can reach 4.93×10^-11 Pa·L/s·cm² after baking at 180°C for 48h, which is more than one order of magnitude lower than that of SS. These results indicate that CuZr alloy is easier to degas by baking at lower temperatures and is a material with very low outgassing rates. At the same time, it is a highly competitive structural material for future accelerator vacuum chamber based on its good electrical conductivity, high strength and hardness.
Paper: THPB079
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPB079
About: Received: 17 May 2025 — Revised: 14 Oct 2025 — Accepted: 14 Oct 2025 — Issue date: 05 Nov 2025
THPM031
Beam Energy Forecasting using Machine Learning at the CLEAR accelerator
2747
In particle accelerators, accurate and stable beam parameters are crucial for experimental success. Traditional methods for measuring parameters like beam energy often rely on invasive techniques that disrupt experiments. This paper presents a novel, non-invasive machine learning-based approach to predict beam energy using parasitic measurements, enabling real-time estimation without interference. The method employs a predictive model optimized for one-step-ahead forecasting and uses time-series data decomposition to handle complex beam energy dynamics. Recursive prediction strategies allow the model to anticipate future variations autonomously. Preliminary results from experiments at the CLEAR accelerator demonstrate the model’s ability to capture both slow trends and rapid energy shifts, adapting to diverse experimental needs. These findings showcase the potential of machine learning to measure beam energy, offering a real-time, non-destructive alternative to conventional methods. This approach promises significant advancements in accelerator-based applications, especially where destructive techniques are impractical.
Paper: THPM031
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPM031
About: Received: 28 May 2025 — Revised: 03 Jun 2025 — Accepted: 06 Jun 2025 — Issue date: 05 Nov 2025
THPM064
Terahertz streaking detection for longitudinal bunch diagnostics at FLUTE
2822
The Karlsruhe Institute of Technology is currently exploring a compact method of longitudinal electron bunch diagnostics with femtosecond resolution that has recently been demonstrated for other parameter ranges. The experimental setup utilizes a THz-based streaking approach with resonator structures, achieving both high compactness and efficiency. In this paper, we report on the experimental observation of streaking signals with our Compact Transverse Deflecting System, which has been successfully tested using two different resonators, an Inverse Split-Ring Resonator and a Tilted-Slit-Resonator.
Paper: THPM064
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPM064
About: Received: 28 May 2025 — Revised: 01 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
THPM091
Extinction Monitoring of Pulsed Proton Beams Using FPGA-Based Peak Detection
2878
The Mu2e experiment at Fermilab imposes stringent requirements on the elimination of out-of-time beam in its pulsed proton beam - a requirement known as "extinction". We present a method to measure the out-of-time particle rates to calculate the level of extinction in the inter-pulse gaps. The proposed method utilizes an array of quartz Cherenkov radiators and photomultiplier tubes to detect particles scattered from a vacuum chamber in the M4 transfer beamline at Fermilab. The measurement will employ a new μTCA-based FPGA system for data acquisition and signal processing, utilizing real-time peak detection algorithms to count scattered beam particles. By integrating data over many transfers, the time profile of the out-of-time beam will be resolved to fractional levels relative to that of the in-time beam. These results are compared with G4beamline simulations to validate models of beam transport, dynamics, and extinction, providing critical input for optimizing beam delivery to Mu2e.
Paper: THPM091
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPM091
About: Received: 28 May 2025 — Revised: 02 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
THPM095
Benchmarking of new approach for analyzing transverse beam emittance measurement
2882
A recent analysis of emittance measurements highlighted the limited reliability of tools for precise method evaluation and error calculations. In this paper, a new analysis method is presented with its associated errors calculations. It is evaluated using realistic beam simulations and compared to the linear regression method commonly referenced in the literature. This new analysis method is shown to be easier to implement and provides results with a good confidence interval.
Paper: THPM095
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPM095
About: Received: 22 May 2025 — Revised: 02 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
THPM099
Results from validation experiment for three-dimensional spiral beam injection scheme
2894
A three-dimensional spiral beam injection scheme\* has been developed since 2014. This scheme is for accumulating a charged particle beam with relativistic energy in a sub-meter storage ring to realize for the J-PARC Muon g-2/EDM experiment (E34). Prior to the E34 experiment, we conducted a demonstration experiment utilizing 80 keV pulsed electron beam generated by an electron gun\**. The beam passed through a transport line of three rotating quadrupoles and was accumulated in an 80gauss solenoid magnet at the center fiducial volume with a diameter of storage orbit only 24cm. Now we have successfully accomplished (1) a strongly X-Y coupled beam phase space to inject into the axisymmetric solenoid magnetic field, (2) a weak focusing magnetic field potential within the storage region at the center of the solenoid magnet, (3) a pulsed magnetic field kick to guide the beam trajectory into the storage region, and (4) beam diagnosis in the storage area. In this presentation, we will report the experimental results of successful storage in an ultra-compact ring, and improvements for the actual storage ring for E34 based on this knowledge gained from 10 years of demonstration experiments.
Paper: THPM099
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPM099
About: Received: 04 Jun 2025 — Revised: 05 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
THPM106
Multimethod signal processing for comprehensive tune coupling characterization at Canadian Light Source
2909
This study compares Fast Fourier Transform (FFT), Power Spectral Density (PSD), and Wavelet Analysis for detecting tune coupling at the Canadian Light Source (CLS). Data were analyzed for low coupling, 1.4%, and 2.5% high coupling regimes, focusing on frequency identification and amplitude stability in X and Y directions. FFT revealed ~15% amplitude fluctuations, complicating tune identification. PSD provided better stability, with only 4% amplitude variations. Both methods were computationally efficient, with FFT taking, 0.0103 seconds and PSD, 0.0108 seconds per calculation. Wavelet analysis preserved temporal-frequency relationships, revealing delays between X and Y frequencies of 2.38 to 4.77 microseconds in the 1.4% regime and peak periods around 18 microseconds. In high coupling, X frequencies preceded Y frequencies, with dominant frequencies showing higher amplitudes than perturbed ones. These findings demonstrate PSD's stability for tune measurements and Wavelet Analysis's ability to capture temporal dynamics, providing insights to enhance beam stability in accelerator systems.
Paper: THPM106
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPM106
About: Received: 23 May 2025 — Revised: 02 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
THPM110
Machine learning for the anomaly detection and characterization of the 24 GeV/c proton beam at CERN IRRAD Facility
2917
The accurate assessment of beam quality is the most important aspect in the irradiation facilities operation such as IRRAD at CERN. The Beam Profile Monitor (BPM) sensor system developed for the high-intensity proton beam at IRRAD features minimal particle interaction, improved radiation hardness and higher sensitivity and sampling rate than previous systems. It provides a wealth of high-quality BPM data not available earlier, enabling the development of data processing more advanced than before. To take advantage already today of this upgraded BPM system’s features, we propose innovative Machine Learning (ML) techniques to adapt and improve upon existing DAQ technology. This paper details the application study of (1) autoencoder architectures to perform the automatic pattern recognition and anomaly detection of proton beam profiles, and (2) deep learning techniques to predict relevant beam parameters. We applied this approach to a new dataset (made publicly available) of BPM data taken during the recent runs of IRRAD; our preliminary results demonstrate good performance in comparison to existing methods. This work is a first step towards the "intelligent" irradiation facilities.
Paper: THPM110
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPM110
About: Received: 28 May 2025 — Revised: 03 Jun 2025 — Accepted: 03 Jun 2025 — Issue date: 05 Nov 2025
THPM111
Characterization of an IRRAD beam profile monitor at the CERN T8 beamline and possible improvements via cross-analysis with multiwire proportional chamber
2921
A new Beam Profile Monitor (BPM) system has been recently developed at the IRRAD Proton Facility to monitor the high-intensity 24 GeV/c proton beam from the CERN Proton Synchrotron accelerator. Thanks to the use of a new sensor manufacturing technology based on the microfabrication of metal nano-layers and updated readout electronics based on a Charge-Sensitive Amplifier with integrated 20-bit ADC and ARM controller, this system features minimal particle interaction, improved radiation hardness and higher sensitivity than earlier solutions. The growing users’ demand for precise irradiation of modern electronics, requiring ever more detailed beam information, is driving the introduction of future IRRAD upgrades, by leveraging on the presence of additional detector, a Multiwire Proportional Chamber, a detailed comparison-based analysis was performed to better characterize the IRRAD BPM system. It allowed us to introduce improvements in beam monitoring via advanced software and data processing. These results are crucial for future improvements at IRRAD by formulating requirements for the profile monitoring of new types of beams in IRRAD, e.g. heavy-ion and low-intensity proton beams.
Paper: THPM111
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPM111
About: Received: 28 May 2025 — Revised: 03 Jun 2025 — Accepted: 03 Jun 2025 — Issue date: 05 Nov 2025
THPS038
Study on a novel laser fast abort system for SuperKEKB
3048
To ensure stable and continuous commissioning of SuperKEKB, the machine protection system (MPS) plays a crucial role in safeguarding the accelerator's hardware from damage caused by beam loss. The response time of the MPS is a critical factor in mitigating hardware damage caused by the radiation of abnormal beams. In this study, we investigate a novel laser fast abort system for the SuperKEKB accelerator to reduce the response time of the beam abort trigger. The laser, serving as the trigger signal, is transmitted through free space. Compared to the traditional method, the transmission speed is 1.5 times faster than that in optical fiber. This faster signal transmission can shorten the abort time, enabling the realization of effective MPS. The optical design for long-distance laser beam propagation and measurement of coupled laser power have been studied. Investigation will be conducted regarding the long-term stability of the laser beam inside the accelerator tunnel.
Paper: THPS038
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPS038
About: Received: 27 May 2025 — Revised: 31 May 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
THPS047
Fully experiment request driven beta* and separation luminosity levelling at the LHC
3072
During the third run period (2022-2026) of the CERN Large Hadron Collider (LHC), as well as for the future High-Luminosity LHC era, luminosity levelling is key to control the event pile-up in the experiments as well as the heat load to the cryogenic system of the superconducting magnets close to the interaction points. During 2024 proton physics operation, a new luminosity levelling scheme was introduced for the high-luminosity experiments, ATLAS and CMS. Combining levelling by optical squeeze (beta*) with small transverse separation changes gives the beam stability benefits of beta* levelling (head-on tune spread and landau damping) while keeping the flexibility of separation levelling (independent levelling for each experiment in arbitrary steps of luminosity). This not only allowed each experiment to set their luminosity target independently, but also reduced the luminosity spread during levelling from 5%, when using just beta* levelling, to less than 3%, resulting in a more homogeneous data set.
Paper: THPS047
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPS047
About: Received: 22 May 2025 — Revised: 30 May 2025 — Accepted: 30 May 2025 — Issue date: 05 Nov 2025
THPS060
Photon stimulated desorption from cryogenic surfaces of high temperature superconductor and amorphous carbon thin films
3101
High Temperature Superconductor (HTS) and amorphous Carbon (a-C) thin films, and their combination, are being considered as possible surface coatings for the FCC-hh beam screen (BS) with the aims of reduction of the resistive wall impedance and mitigation of the electron cloud. Along with these required properties, i.e., the high electron conductivity and low secondary electron yield, the Photon Stimulated Desorption (PSD) yield is one of the most essential characteristics in the design and operation of the FCC-hh vacuum systems. For this purpose, a series of the PSD measurements is currently conducted at a dedicated beamline in the KEK Photon Factory, where similar conditions to FCC-hh in terms of the Synchrotron Radiation energies and power density are available. In order to realize a similar cryogenic condition of the BS (40-60 K), the sample container is equipped with a LN2 jacket (77 K) and installed in an insulation vacuum chamber. The conditioning behaviors of the PSD yields as a function of the photon dose are being obtained for uncoated copper and HTS, and a-C coated copper and HTS, and each sample is examined at cryogenic and room temperatures for comparative analysis.
Paper: THPS060
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPS060
About: Received: 31 May 2025 — Revised: 02 Jun 2025 — Accepted: 03 Jun 2025 — Issue date: 05 Nov 2025
FRZD1
Latest achievements in femtosecond synchronization of large scale facilities
3256
The laser-based synchronisation systems for the European XFEL and FLASH provide femtosecond-stable timing references for tens of clients along the accelerator and the experiment halls over many kilometres of optical fibre. Recently, benchmarking experiments revealed a point-to-point timing stability with sub-femtosecond rms timing jitter. At the same time geophysical effects like ocean waves and earthquakes do not only affect the performance of the system, but their impact can clearly be identified. To improve the temporal resolution in X-ray/optical pump-probe experiments, additional arrival time monitors for both the electrons and the optical laser pulses are currently being installed, allowing for a posteriori data sorting and eventually active feedbacks. Further, the optical reference oscillators and advanced synchronisation schemes are being developed, resulting in timing jitter on the sub-hundred attoseconds level.
Paper: FRZD1
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-FRZD1
About: Received: 30 May 2025 — Revised: 31 May 2025 — Accepted: 01 Jun 2025 — Issue date: 05 Nov 2025