proton
MOPM012
Parameter and luminosity scenarios for FCC-hh
294
In preparation for the 2026 Update of the European Strategy for Particle Physics, various options are being proposed for a future circular hadron collider, FCC-hh. Here, we discuss a few operational scenarios spanning c.m. energies from about 70-120 TeV, which correspond to the arc dipole field strengths ranging from 12 to 20 T. We present the respective integrated luminosity forecasts, considering a proton beam current similar to the one of the existing LHC (0.5 A) or the upcoming HL-LHC (1.1 A), and limiting the total synchrotron radiation power to at most 5 MW. Additional constraints are imposed on the beam-beam tune shift and the maximum event pile-up.on the maximum event pile up.
Paper: MOPM012
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPM012
About: Received: 28 May 2025 — Revised: 31 May 2025 — Accepted: 02 Jun 2025 — Issue date: 05 Nov 2025
MOPM016
Comparison of BCMS and standard beams at LHC injection energy
310
During the Large Hadron Collider (LHC) run in 2024 two beam types were used for physics production with protons. A key difference between the standard 25 ns and the batch compression merging and splitting (BCMS) beams at injection into the LHC, is the smaller transverse emittance achieved with the latter in the injector chain. Despite both beam types appearing indistinguishable in the longitudinal plane, the BCMS beam caused significantly higher beam losses at the start of the acceleration ramp. For the High-Luminosity LHC (HL-LHC) era, start-of-ramp losses could a limitation due to a lack of RF power. It is therefore important to understand the origin of the increase, as both beam types may be used for operational runs after the HL-LHC upgrade. Systematic analysis of the emittance evolution in all three planes have been conducted to investigate the contribution from loss mechanisms like intra-beam scattering (IBS) and RF background noise. Furthermore, estimates of the beam population outside the bunches and start-of-ramp losses are provided to understand the differences in the off-momentum population before the ramp.
Paper: MOPM016
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPM016
About: Received: 26 May 2025 — Revised: 05 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
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
MOPM023
Damage potential and machine protection criticality of the FCC-ee beams
338
The lepton beams of the Future Circular Collider FCC-ee will store 17.5 MJ of energy per beam during Z mode operation. The damage potential of these beams is an essential input for the design of the machine protection system. In this paper, first, the stored energy and energy density of the FCC-ee beams are reported and compared with the values for the Large Hadron Collider (LHC) and the High-Luminosity LHC (HL-LHC). Then, results of energy deposition studies using FLUKA for the generic scenario of a direct beam impact on graphite are presented. Due to the small beam sizes and the distinct shower development, the FCC-ee beams cause peak energy depositions that for Z mode intensities can be comparable to the LHC proton beams. In a last step, the initial hydrodynamic response of the material is simulated using ANSYS Autodyn for a round beam featuring an equivalent peak energy deposition. The calculated temperature rise and density depletion are presented and discussed.
Paper: MOPM023
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPM023
About: Received: 28 May 2025 — Revised: 30 May 2025 — Accepted: 30 May 2025 — Issue date: 05 Nov 2025
MOPM024
Operational experience with automated beam loss analysis in the LHC
342
Every high-energy beam dump event at the Large Hadron Collider (LHC) is analysed to assess the performance of the machine protection system and to identify anomalous behaviour. Analysing the loss pattern of nearly 4000 beam loss monitors, which depends on beam parameters and machine settings, can be time-consuming and requires expert knowledge. Therefore, an automated beam loss analysis tool was developed and deployed in operation in November 2023. It uses empirically derived beam loss thresholds that scale with relevant beam parameters to evaluate beam dumps for post-mortem analysis. The paper describes how the beam loss thresholds were derived and optimised and reviews their performance in proton and Pb-ion operation.
Paper: MOPM024
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPM024
About: Received: 28 May 2025 — Revised: 31 May 2025 — Accepted: 02 Jun 2025 — Issue date: 05 Nov 2025
MOPM091
The European Spallation Source neutrino Super Beam project and physics performance
535
The goal of the ESSnuSB project is to precisely measure neutrino Charge-Parity Violation (CPV). The construction of the European Spallation Source, ESS, represents an outstanding opportunity for such project to take place. ESSnuSB has been funded from EU in the framework of H2020 (2018-2022) and Horizon Europe (2023-2026) to make feasibility studies. The aim of the first phase was to demonstrate that the ESS linac can be used to generate an intense neutrino beam, which coupled with a megaton water Cherenkov detector placed in a mine 360 km from ESS, could allow the detection of neutrinos at the 2nd oscillation maximum. A CDR* has been published in which it is shown the unprecedented physics performance to precisely measure CPV. For this, the modification to compress the proton pulse length from 2.86 ms to 1.3 μs has been studied. The second, ongoing Design Study, ESSnuSB+, is devoted to neutrino cross-section measurements relevant to ESSnuSB. Two facilities are proposed, a low energy nuSTORM (muons decaying to neutrinos in a storage ring) and a low energy ENUBET (pions decaying to a muon and a neutrino and monitoring of the neutrino beam by detection of the decay muon).
Paper: MOPM091
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPM091
About: Received: 20 May 2025 — Revised: 01 Jun 2025 — Accepted: 03 Jun 2025 — Issue date: 05 Nov 2025
MOPM093
Positron contamination in the muon beam at the J-PARC's surface muon beamline (S-line)
542
The surface muon beamline at J-PARC provides high-intensity muon beams that are essential for advanced materials science research, particularly in techniques such as muon spin rotation/relaxation (μSR). However, positron contamination in the beam poses a significant challenge by introducing background noise that affects the measurement precision. Therefore, achieving high-purity muon beams is critical for improving experimental reliability and accuracy. In this study, the G4beamline Monte Carlo simulation toolkit was employed to model the transport of muons and positrons from the production target through the beamline. The system includes a momentum and charge-based separator followed by a collimating slit. While the current slit configuration effectively suppresses positrons, it also causes substantial muon loss of approximately 76%, which significantly reduces the usable muon flux for downstream applications. To address this issue, a detailed investigation into slit size was performed. The results indicate that modest adjustments to the slit aperture size can improve the muon-to-positron ratio while retaining a greater fraction of the muon beam. These results provide valuable guidance for optimizing beamline performance and improving the quality of muon-based experiments at J-PARC.
Paper: MOPM093
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPM093
About: Received: 28 May 2025 — Revised: 02 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
MOPS019
Simulated beam performance of the TWOCRYST proof of principle experiment at the LHC
631
TWOCRYST is a machine test designed to demonstrate the feasibility of an in-vacuum fixed-target experiment for the first direct measurement of the magnetic and electric dipole moments of short-lived charm baryons. This setup exploits crystal channeling using two bent crystals. The first one is similar to the existing crystals used in the LHC for beam collimation, deflecting the beam halo particles from the proton beam onto a target. The second one - a 7 cm silicon crystal - induces spin precession in the secondary particles produced in the target. 2D detectors in movable Roman pots will track the distribution of these channeled particles. A new silicon pixel detector and a fiber tracker (formerly used by the LHC ATLAS-ALFA experiment) are planned for installation in the LHC along with the two crystals in early 2025. Xsuite simulations have been performed to reproduce the multi-turn beam dynamics of the channeled beam halo and the particle distribution expected at the detectors. The LHC configurations required for the planned measurements have also been simulated, with the results used to specify the required detector performance in preparation for benchmarking against real data.
Paper: MOPS019
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPS019
About: Received: 20 May 2025 — Revised: 30 May 2025 — Accepted: 30 May 2025 — Issue date: 05 Nov 2025
MOPS023
Design of the front-end complex for a muon cooling demonstrator at CERN
643
The muon collider has great potential for enabling high-luminosity multi-TeV lepton-antilepton collisions provided low-emittance, high-intensity muon beams can be produced. Ionization cooling is the proposed technique to achieve the required muon beam emittance. The International Muon Collider Collaboration aims to demonstrate the integration and reliable operation of a 6D ionization cooling system, including RF acceleration in strong magnetic fields. This study focuses on the design of the muon production and transport systems for a Muon Cooling Demonstrator facility in the CERN TT7 tunnel. A new implementation based on the CTF3 building is also presented, offering improved layout flexibility and beam intensity. FLUKA simulations are used to optimize the target and magnetic horn geometries to maximize pion production and capture, assuming a 14 GeV proton beam from the Proton Synchrotron (PS). The transport line, designed to deliver 190 – 210 MeV/c muons into the cooling channel, consists of a short pion decay section, followed by a momentum-selecting chicane and a matching section. The chicane integrates collimation and phase-rotation systems for transverse and longitudinal tuning of the muon beam. Beam optics for the transport lattice are designed in MAD-X, with tracking studies performed using BDSIM.
Paper: MOPS023
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPS023
About: Received: 28 May 2025 — Revised: 04 Jun 2025 — Accepted: 05 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
MOPS028
Preparing the future SPS fixed target beams for the SHiP experiment
659
A new high-intensity Beam Dump Facility (BDF), hosting the SHiP (Search of Hidden Particles) experiment, is set to begin operation in CERN’s North Area (NA) in Run 4. To meet its physics goals, SHiP aims at accumulating 4$\times$10$^{19}$ protons on target per year, which will require approximately 10$^6$ high intensity cycles from the SPS with $4.2\times10^{13}$ p$^+$ per cycle (as operationally used during the CNGS era) over a $1$ s spill length. To reduce the future supercycle load and thus minimize the impact on the other physics facilities (especially at the CERN PS complex delivering the beam to the SPS), a strategy involving higher intensity per spill but a smaller number of spills for SHiP was proposed. In this context, a series of studies have been initiated to explore the intensity limits of the North Area beams in the SPS. This contribution presents the initial results on the correction of the intensity dependent tune shift induced by the beam coupling impedance and the transverse optimizations required for operating at higher intensities.
Paper: MOPS028
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPS028
About: Received: 26 May 2025 — Revised: 30 May 2025 — Accepted: 31 May 2025 — Issue date: 05 Nov 2025
MOPS029
High Luminosity LHC collimation system performance for different optics configurations
663
The High Luminosity Large Hadron Collider (HL-LHC) presents significant collimation challenges due to its high stored beam energy. An effective collimation system is critical for ensuring stable operation, protecting the superconducting magnets and minimizing background to the experiments. This paper examines the current baseline collimation configuration and potential changes to the collimation insertion optics to improve the performance in various areas, for both proton and heavy ion beam operation. The study encompasses on- and off-momentum beam loss simulations across various stages of the operational cycle. Collimation performance is assessed based on leakage to superconducting magnets, as well as losses on the tertiary collimators, to probe this source of induced background to the experimental detectors.
Paper: MOPS029
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPS029
About: Received: 28 May 2025 — Revised: 14 Jun 2025 — Accepted: 14 Jun 2025 — Issue date: 05 Nov 2025
MOPS079
Operational deployment of high brightness LHC beams in the SPS
778
Following the LHC Injector Upgrade programme (LIU) there has been a gradual ramp-up of the intensity of LHC beams in the CERN Super Proton Synchrotron (SPS). This was initially hampered by vacuum issues in several critical components, such as RF cavities and kicker magnets, requiring extensive scrubbing campaigns to condition these components. This paper reviews the current status of the high brightness LHC beams in the SPS, including commissioning evolution, aspects related to beam stability and beam optimization and the current brightness reach. An assessment of the operational readiness of these beams for the High Luminosity LHC era is also given.
Paper: MOPS079
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPS079
About: Received: 26 May 2025 — Revised: 04 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
MOPS095
Plan for the KOMAC proton linac upgrade to 200 MeV
797
A 100-MeV proton linac has been operated for over 10 years at KOMAC and used for proton beam services. We are planning to upgrade the linac energy to 200-MeV. By increasing the linac beam energy, we expect the machine to be capable of serving wider application fields including space radiation tests of semiconductor devices and material tests by using high-energy neutrons generated by bombarding a proton beam to a solid target. For the energy upgrade, we consider the SDTL structure for the 200-MeV section. The structure of SDTL is relatively simple so we may reduce the risk and time of development. In addition, we can avoid complex cryogenic systems by choosing a normal conducting approach. For the beamline, two separate target rooms (one for proton, and the other for proton and neutron irradiation) are under design. Details of the planning activity for the KOMAC linac upgrade will be reported in this presentation.
Paper: MOPS095
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPS095
About: Received: 28 May 2025 — Revised: 05 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
MOPS115
A muon beam facility at CERN to demonstrate muon ionisation cooling
803
The International Muon Collider Collaboration (IMCC) has been formed following the 2020 European Strategy for Particle Physics Update, with the goal of studying the feasibility of a muon collider at a centre of mass energy of around 10 TeV. One of the most challenging sections of a muon collider is the initial cooling before acceleration, due to the necessity to apply intense magnetic and electric fields to reduce the 6D emittance of the muon beam by 5 orders of magnitude in a very short time, to cope with the limited lifetime of muons (2.2 μs at rest). The IMCC proposes to build a Demonstrator to prove that all the involved technologies (RF, magnets, absorbers, beam instrumentation) can be built at the required specifications, and integrated in order to limit the length of the cooling sections to an acceptable value. Several options are being considered in different laboratories within the collaboration. This paper describes a possible implementation at CERN, in the existing TT7 tunnel.
Paper: MOPS115
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPS115
About: Received: 28 May 2025 — Revised: 04 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
MOPS143
Feasibility studies for a new transfer line to a muon cooling demonstrator at CERN
840
In the context of ongoing research for a future muon collider, one of the primary challenges is the efficient production and cooling of muons. To address this, a proposal is being explored to construct a demonstrator at CERN for testing a cooling cell. This demonstrator would include a target and focusing system, a chicane around a dump, and a cooling channel. A potential site for this facility is the end of the existing TT7 tunnel, which was used as a neutrino facility in the early 1980s and is presently used for storage of radioactive waste. This paper outlines the initial design studies for the transfer line that will deliver 14 GeV protons from the Proton Synchrotron to the target. The design aims to minimize costs while meeting all geometric and optical requirements. The possibility of operating the line up to 20 GeV is also explored.
Paper: MOPS143
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPS143
About: Received: 26 May 2025 — Revised: 02 Jun 2025 — Accepted: 03 Jun 2025 — Issue date: 05 Nov 2025
TUYN1
Electron-Ion Collider status
878
The Electron-Ion Collider (EIC), which is being designed by BNL, JLab and other partners, will be a particle accelerator that collides electrons with protons and nuclei to produce snapshots of those particles' internal structure. It will collide polarized high-energy electron beams with hadron beams in the center-of-mass energy range of 20-140 GeV. The electron beam, employed as a probe, will reveal the arrangement of the quarks and gluons that make up the protons and neutrons of nuclei. The EIC will allow us to study the "strong nuclear force", the role of gluons in the matter within and all around us, and the nature of particle spin. This talk will describe the Electron-Ion Collider design and construction at Brookhaven National Lab.
Paper: TUYN1
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUYN1
About: Received: 28 May 2025 — Revised: 29 May 2025 — Accepted: 01 Jun 2025 — Issue date: 05 Nov 2025
TUBN2
RHIC polarized proton operation in Run24
895
The Relativistic Heavy Ion Collider (RHIC) Run 24 was 27 cryo weeks, operating with collisions at the STAR and sPHENIX detectors. The primary mode was polarized protons at 100 GeV, where there was 22 weeks of physics production. sPHENIX continued commissioning, becoming fully operational after 13 weeks and the addition of isobutane to their TPC gas mixture. STAR had a low luminosity run followed by twenty weeks of high luminosity and radially polarized beams. To reduce the beam-beam parameter and maximize the number of collisions within a small vertex region at sPHENIX, sPHENIX planned to operate with a crossing angle. For 8 weeks, collisions were only at sPHENIX until the beam-beam parameter was sufficiently low to support the additional collisions at STAR. A significant number of power dips earlier in the run greatly affected machine performance and reliability. At the maximum achieved performance, the luminosity was limited by four factors simultaneously: accelerating RF cavity intensity limit, intensity from the injectors, losses at rebucketing, and dynamic aperture. Despite these difficulties, sPHENIX and STAR were able to collect sufficient data commensurate with their goals.
Paper: TUBN2
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUBN2
About: Received: 29 May 2025 — Revised: 31 May 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
TUZN2
Compact hadron sources and linacs for societal applications
909
CERN Linac4 was formally approved in 2007 in the framework of the LHC Injector Upgrade Project with the purpose of removing the first intensity bottleneck in the chain of CERN LHC injectors. Linac4 was inaugurated in 2017 and became the sole proton injector at CERN in 2020. The experience and know-how built over a decade through the Linac4 project has subsequently been applied to accelerators for societal applications via the Medical Application Office and the Knowledge Transfer Group at CERN. In this paper, we discuss the specific needs of accelerators for societal applications in terms of compactness, portability, and operability. We describe the specific beam dynamics that allow meeting those challenges and illustrate a few examples realized for medical applications and the analysis of fine art.
Paper: TUZN2
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUZN2
About: Received: 25 May 2025 — Revised: 02 Jun 2025 — Accepted: 03 Jun 2025 — Issue date: 05 Nov 2025
TUPB003
Beyond 1 MW operation of the J-PARC RCS
936
Beyond 1 MW operation of the J-PARC RCS The 3-GeV Rapid Cycling Synchrotron (RCS) of the Japan Proton Accelerator Research Complex (J-PARC) has already been achieved the designed 1 MW operation to the Material and Life Science Experimental Facility (MLF). However, to cope with the gradually getting faster operation cycle of the main ring synchrotron sharing more beam requires RCS to accelerate more than 1 MW beam per pulse for the MLF to ensure net 1 MW beam power at the MLF. Moreover, the beam sharing to the under designed 2nd MLF target facility has also to be considered. As a result, the next goal is to realize 1.5 MW beam power first and continue for 2 MW or even more. This will be done by injecting more particles in the RCS by increasing both peak current and pulse duration of the injection beam. Beam dynamics issues and possible scenarios to realize far beyond 1 MW in the RCS are presented.
Paper: TUPB003
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB003
About: Received: 29 May 2025 — Revised: 02 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
TUPB006
Readiness of the HEARTS@CERN facility for space electronics high-energy heavy-ion testing
948
The HEARTS@CERN activity in the framework of the HEARTS (High-Energy Accelerators for Radiation Testing and Shielding) EU project is targeted at enhancing Europe’s high-energy (>100 MeV/n) heavy ion electronics irradiation capability through the development of an irradiation beam combining unique penetration and ionization characteristics. These types of tests are essential for exploiting commercial electronics in space. Throughout 2024, the HEARTS@CERN efforts have focused on achieving and demonstrating compliance with the space user radiation effects testing requirements. This includes being able to offer a wide range of energies (and Linear Energy Transfer values) and fluxes, with a high level of accuracy and a rapid change between parameters. Moreover, large homogeneous beams are necessary for enabling the test of multiple electronic components in parallel, and for performing board level testing. This work will present requirements for high-energy heavy ion testing along with the level of compliance achieved, as demonstrated during the November 2024 HEARTS@CERN user run, with a focus on the beam related parameters, but including also facility and procedural considerations.
Paper: TUPB006
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB006
About: Received: 27 May 2025 — Revised: 03 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
TUPB007
Radiation levels from a Beam Gas Curtain instrument at the LHC at CERN during ion operation
952
A prototype Beam Gas Curtain (BGC) monitor was installed on beam 1 at the Large Hadron Collider (LHC) at CERN to provide 2D images of the transverse beam profile during the ongoing Run 3 (2022 - to date) and in view of the High Luminosity LHC upgrade (HL-LHC). By design, the BGC operation generates collisions between the beam particles and an injected gas jet proportionally to the beam intensity and the gas density, possibly causing radiation-induced issues to the downstream LHC equipment. This operation has been studied for the proton run, and now the scenario for lead (Pb) ion beam is scrutinized. The radiation showers from the BGC are characterized using measured data from different LHC radiation monitors during the Run 3 BGC operation, along with Monte Carlo simulations with the FLUKA code. Finally, predictions of the expected radiation showers during operation of the BGC in the HL-LHC era are discussed.
Paper: TUPB007
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB007
About: Received: 28 May 2025 — Revised: 29 May 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
TUPB020
Injection simulations of space charge dominated proton beams in IOTA
995
A 2.5 MeV proton injector is being constructed for the IOTA ring at Fermilab to study the interaction of nonlinear integrable optics (NIO) with high space charge beams. Space charge in the transport line from the RFQ to the injection location has a significant current dependent effect on the phase space. Simulation studies to support efficient injection of intense bunches into IOTA are presented, included schemes to inject directly into NIO lattices.
Paper: TUPB020
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB020
About: Received: 28 May 2025 — Revised: 30 May 2025 — Accepted: 30 May 2025 — Issue date: 05 Nov 2025
TUPB023
Simulation studies on bent silicon crystals for loss reduction in slow extraction operation at J-PARC Main Ring
1006
Reducing beam loss during slow extraction remains a critical challenge for the J-PARC Main Ring, which aims to enhance beam power for its 30 GeV proton beam. Since beam loss during slow extraction mainly occurs at the electrostatic septum, it is important to reduce beam loss at this location. Researchers at CERN SPS have recently reported that beam loss can be reduced by installing bent silicon crystals in the accelerator ring and utilizing their charged particle deflection effect. In this paper, we report the results of a simulation study on the expected beam loss reduction effect when the bent silicon crystal is installed upstream of the electrostatic septum of the J-PARC Main Ring and the beam deflection effects of the bent silicon crystal, called channeling or volume reflection, are utilized. The required size and installation position of the silicon crystal, and the required accuracy for adjusting the position and angle will also be reported.
Paper: TUPB023
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB023
About: Received: 28 May 2025 — Revised: 03 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
TUPB024
Simulations of magnetic field effects on 3-GeV proton beam brought by magnets for muon beam in future proton beam transport line of J-PARC
1010
A high-power 3-GeV proton beam from a rapid cycling synchrotron (RCS) is transported to targets for muon and neutron production at Materials and Life Science Experimental Facility (MLF) by a 3-GeV RCS to Neutron facility Beam Transport (3NBT) line in J-PARC. Recently, the design power of 1 MW has been achieved, which has initiated a future plan of MLF second target station (TS2). For the future plan, design studies have been started for a new beam transport line to the TS2 target, which works as a source for both muon and neutron. In this study, 3-GeV proton beam transport is simulated in the vicinity of the TS2 target, where a bending magnet for muon separation and a capture solenoid are aligned. In this presentation, we report magnetic field effects on the proton beam brought by those magnets and correction of the effects.
Paper: TUPB024
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB024
About: Received: 07 Apr 2025 — Revised: 02 Jun 2025 — Accepted: 03 Jun 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
TUPB030
Characterisation of transverse proton beam losses at the CERN Super Proton Synchrotron
1033
The High-Luminosity LHC (HL-LHC) project foresees nearly doubling the design beam intensity of CERN's Large Hadron Collider (LHC). A particularly pressing issue is the observation of significant beam losses at the flat bottom in the Super Proton Synchrotron (SPS) that delivers these beams to the LHC. These losses arise from multiple factors: uncaptured beam losses that are generated during the bunch rotation in the Proton Synchrotron (PS) before the transfer to the SPS; large transient beam loading effects in the RF system during multi-turn SPS injections; and the diffusion of over-populated transverse tails, which reach aperture limitations. Dedicated beam measurements were carried out in the SPS as a first step towards untangling these losses. These studies aimed to disentangle the various loss mechanisms, with a focus on the halo population and potential correlations between transverse and off-momentum tails.
Paper: TUPB030
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB030
About: Received: 25 May 2025 — Revised: 04 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
TUPB032
Application of bayesian optimization in magnetic horn design
1040
Bayesian optimization is an effective method for designing complex systems with costly, non-analytic black box objective functions. It enables efficient exploration of the parameter space, making it well-suited for challenging problems in accelerator design which involve computationally intensive simulations such as FLUKA. This study presents a framework to apply Bayesian optimization techniques to design the magnetic horn of Neutrinos from Stored Muons (nuSTORM) experiment for increased pion capture. The optimization process spans a wide range of operational energies, from 1 to 7 GeV, to address the physics reach of nuSTORM. Batch sampling is enabled through specialized acquisition functions, allowing simulations to run in parallel across a computational cluster and significantly reducing the time needed to identify optimal target and horn configurations for the muon source. By leveraging the surrogate models generated through Bayesian optimization, horn configurations at different energies are systematically compared. This facilitates sensitivity studies to determine a minimal set of horn designs that efficiently cover the nuSTORM kinematic range.
Paper: TUPB032
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB032
About: Received: 28 May 2025 — Revised: 01 Jun 2025 — Accepted: 02 Jun 2025 — Issue date: 05 Nov 2025
TUPB042
Optimising focusing parameters of very high energy electron beams for radiotherapy using Monte Carlo simulation
1063
Very high energy electron (VHEE) beams, with energies of 100 MeV and above, offer favourable properties for radiotherapy, such as deep penetration depth and reduced sensitivity to tissue heterogeneity. Numerous simulation and experimental studies have investigated these properties for clinical application. In this study, we use Monte Carlo simulation using TOPAS to obtain the depth-dose profiles of VHEE beams with varying energy and focusing parameters. An empirical model is fitted to the central axis dose, yielding parameters that characterise the depth-dose profile. A linear interpolator then maps these fitting parameters to the focusing parameters, allowing us to identify the optimal focusing parameters. The results presented here are independent of the beamline and can therefore guide the design of a final focusing systems for VHEE beams.
Paper: TUPB042
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB042
About: Received: 27 May 2025 — Revised: 30 May 2025 — Accepted: 31 May 2025 — Issue date: 05 Nov 2025
TUPB048
Installation, operations, and upgrade of a CS-30 cyclotron for the production of alpha emitters At-211 and Ac-225 at the Ionetix TAT facility
1075
Ionetix Corporation has been conducting research and development on compact superconducting cyclotrons for medical isotope production, with multiple Ion-12SC units installed and operated at customer sites in USA. Since 2021, we have also focused on the production of alpha-emitting medical isotopes for cancer therapy, specifically At-211 and Ac-225. As a first step, Ionetix acquired an existing, partial CS-30 Cyclotron system decommissioned and stored in a warehouse. We refurbished and upgraded the CS-30 cyclotron, replacing components as needed. The installation of the CS-30 was completed in 2022, and it has been operational, accelerating alpha and proton beams since 2023. The refurbished cyclotron features new main and trim coils, a new internal bismuth target and drive, and a new central region to enhance the beam-on-target performance. All power supplies, controls, and instrumentation were replaced with commercially available components. The first production of At-211 at Ionetix was achieved in April 2023, followed by the first production of Ac-225 in June 2024. This paper analyzes and describes the CS-30 cyclotron, and the upgrades and enhancements developed at Ionetix.
Paper: TUPB048
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB048
About: Received: 28 May 2025 — Revised: 04 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
TUPB049
Development and Future Applications of the NARI 70 MeV Cyclotron
1079
The National Atomic Research Institute (NARI) is developing a 70 MeV proton cyclotron, with construction set from 2023 to 2027. The cyclotron is designed to operate at proton energies from 28 to 70 MeV and a maximum current of 1000 micro-amperes. It will serve three main purposes: (1) medical isotope production, (2) proton irradiation testing, and (3) cyclotron-based neutron source development. NARI aims to ensure a stable supply of radioisotopes for nuclear medicine, such as Tl-201, I-123, and Ga-67, while advancing the development of isotopes like Cu-67 and Mo-99. In addition to medical uses, the cyclotron will simulate space radiation environments for aerospace materials testing and radiation measurement standards. The cyclotron will also support neutron-based technologies, benefiting nuclear physics, new materials, and industrial applications. Neutron research will occur in two phases: Phase I (2023–2026) will establish a thermal neutron target station for neutron diffraction studies, and Phase II (2027–2030) will develop a quasi-monoenergetic neutron (QMN) source for soft error rate testing in electronics and a high-resolution neutron imaging station. Expected to be fully operational by 2028, the facility will include seven beamlines, two solid target stations, one gas target station, and specialized laboratories for proton, fast neutron, and thermal neutron research. The NARI 70 MeV cyclotron will support both routine isotope production and advanced scientific research.
Paper: TUPB049
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB049
About: Received: 29 May 2025 — Revised: 13 Oct 2025 — Accepted: 13 Oct 2025 — Issue date: 05 Nov 2025
TUPB067
Development of a new cyclotron concept for medical application
1116
Further development of a cyclotron design concept with advantages, such as energy efficiency and cost-effectiveness, is presented. The concept is optimized for non-superconducting cyclotrons. The main feature of the concept is the operation at high frequency (145 MHz) of the accelerating system.
Paper: TUPB067
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB067
About: Received: 28 May 2025 — Revised: 01 Jun 2025 — Accepted: 05 Jun 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
TUPB082
Development of an optical diagnostics system for ion sources
1136
At iThemba LABS proton beams, extracted from an ion source, are pre-accelerated in an injector cyclotron and further accelerated in a K200 cyclotron and transported to various target stations used for radionuclide production. To gain a deeper understanding of the various processes occurring inside the plasma reservoir of the ion source and to support operational adjustments of the ion source, a novel optical emission diagnostics system is being developed in collaboration with the ISIS Facility of the Rutherford Appleton Laboratory. The proposed work builds on pioneering development of optical diagnostics of ion source plasmas and high-current beam-induced light emission at ISIS. The optical signals generated in the plasma and extraction region are collected and transported via an optical fibre to a diagnostics unit with multiple detectors suited for varying intensities and required temporal resolutions. Wavelengths of various emission lines are selected using bandpass filters. From this unit the signals are sent to a data acquisition system for processing. This contribution will present a preliminary design of the optical diagnostics system and the status of prototyping activities.
Paper: TUPB082
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB082
About: Received: 26 May 2025 — Revised: 03 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
TUPB091
Dose calculations for warm quadrupoles in the LHC off-momentum cleaning insertion
1143
Interaction Region 3 (IR3) of the Large Hadron Collider (LHC) houses the off-momentum collimation system, designed to remove particles with significant energy deviations. The interaction of the beam with this multi-stage collimation system generates particle showers that impact various elements, including quadrupole magnets in the straight section. Radiation exposure to magnet coils and spacers raises concerns about potential damage. The upcoming High-Luminosity (HL) LHC upgrade will significantly increase radiation doses, necessitating further assessments. While shielding inserts were added to the quadrupoles during a previous shutdown, further shielding may be required, prompting dose predictions through the HL-LHC era in the 2040s. This paper presents FLUKA simulations where the off-momentum proton and heavy ion losses in LHC Run 2 (2014-2018) and Run 3 (2022-2026) is estimated from Beam Loss Monitors. These estimates serve as normalization factor for calculating the dose deposited in the quadrupoles. These results are then extrapolated to HL-LHC operational parameters, offering unprecedented insight into the future IR3 radiation environment
Paper: TUPB091
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB091
About: Received: 26 May 2025 — Revised: 22 Oct 2025 — Accepted: 22 Oct 2025 — Issue date: 05 Nov 2025
TUPB103
Status update of the laser-hybrid accelerator for radiobiological applications
1155
The Laser-hybrid Accelerator for Radiobiological Applications (LhARA) is a transformative approach to ion-beam therapy and radiobiological research. Serving the Ion Therapy Research Facility (ITRF), LhARA proposes to use a laser-driven proton and ion source, combined with advanced beam delivery systems, to provide highly flexible, high-repetition-rate, and ultra-short ion bunches suitable for groundbreaking studies in radiobiology. Following the recent publication of the LhARA Conceptual Design Report, the LhARA/ITRF project has entered a new phase of research and development. Here, we present a status update on recent LhARA progress. Highlights include improved understanding of the simulated beam generated at the source as well as subsequent impact on beam dynamics with co-propagating electrons, the latest descriptions of the FFA magnets including simulated fields and tune calculations in particle tracking and updated to beam delivery schemes in LhARA’s end stations for generating flexible beam conditions.
Paper: TUPB103
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB103
About: Received: 28 May 2025 — Revised: 02 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
TUPB105
A compact synchrotron for cancer therapy with helium ions
1159
In the frame of the Next Ion Medical Machine Study (NIMMS) collaboration based at CERN, a compact synchrotron for radiotherapy with high-intensity helium beams is designed. Interest in helium ions is growing in the major treatment centers, since they provide superior accuracy compared to protons, thanks to their sharper lateral penumbra, and higher linear energy transfer. Their properties lie in-between protons and carbon ions, without the fragmentation problems of the latter. Moreover, their lower magnetic rigidity allows helium-ion accelerators to be more compact than the large carbon-ion machines. The synchrotron design presented in this paper is based on normal-conducting dipole magnets at 1.65 Tesla and has a circumference of 35 meters. Optimized for helium ions, it can also accelerate protons, for treatment and particle radiography, and other species to smaller penetration depths. The design choices for the different systems are described taking into consideration the mechanical integration in a compact layout and operational flexibility. The technology readiness level is evaluated and R&D options to achieve higher performances and reduce energy consumption are identified.
Paper: TUPB105
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB105
About: Received: 28 May 2025 — Revised: 02 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
TUPM025
Conceptual design of a compact synchrotron for proton-and-helium therapy facility
1212
In recent years, proton and heavy-ion therapy has become increasingly widespread in clinical applications, and has emerged as one of the important means for cancer treatment. The commonly used particle types for this therapy are protons and carbon ions. However, further research into the biological effect has found that helium ions have both high biological effectiveness and small penumbra characteristics, which enable more precise locate of the tumor while also effectively killing tumor cells. And the highest energy of the helium ions used in therapy is 235MeV/u. Therefore, the equipment size and cost required for helium ions therapy will be significantly less than that for carbon ions therapy. To this end, this paper proposes a design for a helium-ion therapy synchrotron that also possesses the capability for proton therapy. The design employs eight ultra-high field dipole magnets to achieve a compact envelope function. Additionally, the design incorporates both multi-turn painting injection and mismatched injection methods in two directions, significantly minimizing the use of bump magnets. This results in a highly compact accelerator structure.
Paper: TUPM025
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPM025
About: Received: 03 Apr 2025 — Revised: 30 May 2025 — Accepted: 03 Jun 2025 — Issue date: 05 Nov 2025
TUPM077
New developments in the design of the muon production target area of a multi-TeV muon collider
1333
As the International Muon Collider Collaboration advances the conceptual design for a multi-TeV muon collider facility, new technical constraints continue to arise in the muon production stage, where a high-power proton beam interacts with a target. Achieving the required muon bunch intensity may necessitate increasing the primary beam power up to 4 MW. Consequently, the shielding design must address sustained radiation exposure, particularly on critical components such as superconducting solenoids, which generate strong magnetic fields essential for capturing both pions and decay muons. Additionally, the portion of the proton beam that passes through the target without undergoing inelastic interaction leads to a very high power density in the chicane area and an intense ionising dose on the insulation material of the normal-conducting chicane magnets, which are used to separate the muon component. A robust method to safely extract these spent protons is crucial. This study presents the latest results from FLUKA Monte Carlo simulations, modelling the radiation load on solenoids and the extraction channel across varying beam power and target designs.
Paper: TUPM077
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPM077
About: Received: 27 May 2025 — Revised: 01 Jun 2025 — Accepted: 01 Jun 2025 — Issue date: 05 Nov 2025
TUPM090
An energy recovery proton linear accelerator for muon production
1365
Muons have important applications in both scientific research and industry. In order to produce muons, an effective way is to use a high-power proton beam interacting with a targeting material. After the interaction, the proton beam is disposed of for other purposes. In this paper, we propose a new type of proton accelerator, an energy recovery proton linear accelerator, so that the high-energy proton beam can be reused to give its energy back to the accelerator. This substantially saves the operational cost of the accelerator and also avoids the burden of high-power beam dumps.
Paper: TUPM090
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPM090
About: Received: 20 May 2025 — Revised: 31 May 2025 — Accepted: 31 May 2025 — Issue date: 05 Nov 2025
TUPS006
Proton-driven plasma wakefield acceleration for high-energy lepton beams
1422
Future colliders with discovery potential for particle physics rely on increasing the parton centre of mass (pCM) energy, with the recent P5 report calling for a 10 TeV pCM collider. However, the development of such schemes using conventional accelerator technology would result in ever-larger facilities. High-gradient plasma wakefields driven by proton beams allow the transfer of energy to a witness bunch over a short length scale, and so offer a potential method to transform high-energy proton beams into high-energy lepton beams while requiring relatively little additional civil engineering. The application of this concept to a Higgs factory driven by 400 GeV protons was recently proposed*. In the present work, we discuss the ongoing efforts to address the challenges to realising such a scheme**, and possible upgrade paths to particle physics applications beyond a Higgs factory.
Paper: TUPS006
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPS006
About: Received: 28 May 2025 — Revised: 04 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
TUPS029
Present status of RF system upgrade in the J-PARC MR
1479
J-PARC MR delivers 30 GeV proton beams to the neutrino facility and the hadron experimental facility, and an upgrade plan is underway to increase beam power by shortening the MR cycle time and increasing the number of particles per bunch. As a result, the beam power for neutrino experiments has achieved its original design value of 750 kW in 2023 and reached 800 kW in 2024. The target beam power of this upgrade plan is 1.3 MW for the Hyper-Kamiokande experiment.The current RF system consists of 9 fundamental cavities and 2 second harmonic cavities for a total of 11 RF systems, but it is necessary to add two more fundamental cavities to further shorten the MR cycle time. Preparations are underway to begin operation of the 10th RF system in 2025 and the 11th in 2027. In addition, as the number of particles increases, further beam loading compensation will be required, so we are also working on upgrading the RF source. We present the progress of the MR RF system upgrade.
Paper: TUPS029
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPS029
About: Received: 28 May 2025 — Revised: 05 Jun 2025 — Accepted: 05 Jun 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
TUPS032
Wien filter method for the "Quasi-frozen" spin lattice
1491
To study the electric dipole moment of light nuclei, it is necessary to maintain the direction of the spin along the particle's motion along the ring. The first obvious solution to this problem is to use elements with an electric field that rotates the spin in the direction opposite to the spin rotation in a magnetic field. The most successful solution in this case is the Wien filter, which ensures spin rotation while maintaining the co-direction of the spin and momentum. In this case, the ring structure consists of arcs with bending magnets and straight sections on which Wien filters with crossed electric and magnetic fields are installed. The paper considers various versions of a magneto-optical structure that implements the "Quasi-frozen" spin method for studying the electric dipole moment of deuterons and protons. This approach can be used in developing an upgraded Nuclotron structure.
Paper: TUPS032
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPS032
About: Received: 25 Apr 2025 — Revised: 13 Oct 2025 — Accepted: 13 Oct 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
TUPS038
Low energy beam transport line design for the Sarajevo ion accelerator
1510
The University of Sarajevo Physics Department, in collaboration with CERN’s Accelerator Beam Physics group, proposes a compact linear accelerator design for applied physics research spanning from beam dynamics studies to material surface analysis. The Sarajevo Ion Accelerator (SARAI) consists of an electron cyclotron resonance ion source, a low energy beam transport line (LEBT) and a radiofrequency quadrupole (RFQ). The ion source can produce an array of ions extracted with 30 kV. This study presents an iterative parameter optimization method that suggests two LEBT optics: one for beam diagnostics and another for compact beam matching to the RFQ acceptance. The RFQ discussed here is a 750 MHz, 2.5 MeV/u RFQ, used for medical applications. SARAI RFQ aims at 0.5 - 2 MeV/u. A novel RFQ technology allows a significant reduction in footprint. This paper further discusses plans for source commissioning and potential research applications.
Paper: TUPS038
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPS038
About: Received: 27 May 2025 — Revised: 02 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
TUPS056
First beam through the superconducting linac of European Spallation Source
1560
The European Spallation Source (ESS), currently under construction in Lund, Sweden, is designed to be the brightest neutron source in the world. It will be driven by a superconducting proton linac with a design beam power of 5 MW and energy of 2 GeV. The construction and installation of the linac are completed for the initial user operation envisaged in 2026 with capability of 2 MW beam power and 800 MeV energy. Beam commissioning of the full linac up to the dump in the line of eyesight is planned in early 2025. At this stage, the main focus will be on establishing optimal transport of 800 MeV beam as well as validating the critical components such as the RF system, diagnostics devices and machine protection systems. This contribution presents the highlights from this commissioning phase that will send the beam through the superconducting linac of ESS for the first time.
Paper: TUPS056
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPS056
About: Received: 27 May 2025 — Revised: 02 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
TUPS136
Characterization of the energy spectrum of a 30-MeV cyclotron-based quasi-monoenergetic neutron beam using a time-of-flight spectrometer
1633
We conducted time-of-flight (TOF) measurements to characterize the spectrum of a quasi-monoenergetic neutron beam driven by a 30-MeV proton cyclotron at the National Atomic Research Institute in Taiwan*. Neutrons were produced by irradiating 30-MeV protons onto a 1-mm-thick beryllium target. The developed TOF spectrometer comprised two 2-inch EJ-309 organic scintillators positioned 200 mm from the neutron beam port to detect gamma rays emitted from the target, and a 3-inch EJ-309 scintillator placed at a flight distance of 2940 mm to measure neutrons. As the signals of gamma-ray bursts triggered TOF measurements at an RF frequency of 73.13 MHz, repetitive distributions of coincidence events between gamma-ray and neutron-related signals were observed, resulting in an effective time window of 13.67 ns for measuring neutrons in the energy range of 16.19–30 MeV. The measured neutron spectrum exhibited a peak at 26 MeV, verifying the simulated spectrum obtained from an MCNP Monte Carlo model. Additionally, we developed a fast-timing scintillator module that measured the proton bunch duration as 0.97 ns, enabling accurate estimation of the energy resolution of the neutron spectrum.
Paper: TUPS136
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPS136
About: Received: 24 May 2025 — Revised: 31 May 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
TUPS140
Design of Pelletron accelerator using novel accelerating tube without gap insulators
1637
A novel modular electrostatic accelerating tube*, free from gap insulators, is designed that addresses the limitations of traditional metal-insulator bonded accelerating tubes**, which are costly and prone to damage from high-voltage discharges and beam impacts. This design uses ultra-high vacuum (UHV) as the insulator, with electrodes placed in series under vacuum. High voltage is coupled longitudinally to the first cylindrical electrode via a ceramic-bonded stainless steel flange, with homogeneous electric field flatness of 0.001. Electrostatic analysis using COMSOL Multiphysics and TRAVEL code confirms the field homogeneity and smooth beam acceleration, respectively. Designed for 75 kV operation, extendable to q×100keV energy gains, it leverages vacuum-compatible resistors for inter-electrode HV coupling. Field flatness is extendable to few meters of length and thus enabling megavolts. Beam optics and electrical specifications for Pelletron accelerators using these tubes supports practical feasibility. The grounded cylindrical structure ensures safety and offers an economical, scalable design for small low-energy implanters, Pelletron accelerators, and mass spectrometers.
Paper: TUPS140
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPS140
About: Received: 29 May 2025 — Revised: 01 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
TUPS151
Preliminary study of beam dynamics for SDTL-Based 200 MeV energy upgrade of KOMAC proton linac
1640
Korea Multipurpose Accelerator Complex (KOMAC) proposes an energy upgrade of the 100 MeV proton linac. The design of the extended linac is based on a normal-conducting separated-DTL (SDTL) structure which has several advantages over other accelerating structures. The SDTL structure is the same as the DTL, however, unlike the general DTL, the quadrupole magnet is not placed inside the DT but is placed outside. This adds more flexibility to optimize the DT structure for better accelerating efficiency. In addition, since only 4 DTs are placed in the SDTL tank, a separated field gradient stabilization device is not needed, so it is known to be easier to manufacture and align than the general DTL. Our upgrade design consists of a beam matching section between the SDTL and the existing DTL, and 20 SDTL tanks each containing four drift tubes (DTs) with a doublet focusing lattice structure. Beam dynamics simulations were performed using an optimized DT structure to accelerate proton beams from 100 to 200 MeV. We report the preliminary beam dynamics study of the 200 MeV SDTL linac carried out at KOMAC.
Paper: TUPS151
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPS151
About: Received: 28 May 2025 — Revised: 02 Jun 2025 — Accepted: 06 Jun 2025 — Issue date: 05 Nov 2025
WEAN1
Measurement techniques using the electron beam profile scanner at the Fermilab Main Injector
1670
This work presents techniques for non-invasive transverse profile measurements of high-intensity proton beams using an Electron Beam Profile Scanner (EBPS). The EBPS utilizes low-energy electrons as a probe to analyze the transverse size of proton beams, allowing for potential analysis on a single-bunch basis. Recent upgrades to the Fermilab Main Injector have enhanced beam power on target to 1 MW, with future developments targeting 2 MW. The higher beam power has increased the demand for non-invasive diagnostics, as invasive methods can disrupt operations. The techniques presented include 1) the slow scan technique, which serves as a proof of concept for the probe beam, 2) the one-shot scan technique for measuring horizontal beam profiles, and 3) the raster scan technique for analyzing horizontal beam profiles as a function of the longitudinal distribution of the beam. The profiles obtained will be crucial for studying and understanding instabilities in high-power, high-intensity proton beams. This will contribute to optimizing the operation of high-power proton accelerators by minimizing beam loss, activation, and damage to both the diagnostics and the accelerator components.
Paper: WEAN1
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEAN1
About: Received: 01 Jun 2025 — Revised: 05 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
WEAN3
Supersonic gas curtain-based in-vivo transverse beam profile monitoring for medical accelerators
1678
To ensure patient safety, treatment effectiveness, and facility efficiency, each ion beam therapy facility requires a complete online characterization of the charged particle beam. Existing dosimetry methods are either limited in the information they provide or invasive to the beam, highlighting the need for new in-vivo dosimetry solutions. Since 2015, the QUASAR Group at the Cockcroft Institute, UK has been developing non-invasive beam monitors for medical accelerators. Accurate monitoring of the transverse beam profile is the first step toward achieving in-vivo dosimetry. The monitor, under development, utilizes a supersonic gas curtain that interacts with the charged particle beam, using the resulting impact ionization to measure the transverse beam profile. A prototype monitor was successfully tested for proof-of-concept measurements at the Dalton Cumbrian Facility’s pelletron accelerator (UK). Measurements were conducted using various beam parameters with both proton and carbon ion beams. This contribution presents the monitor's design and operating principle, experimental results from the measurements, and additional planned improvements aimed at achieving in-vivo dosimetry.
Paper: WEAN3
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEAN3
About: Received: 21 May 2025 — Revised: 02 Jun 2025 — Accepted: 02 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
WEPB085
Design and development of an extraction septum for the MYRRHA 100 MeV proton target facility
1918
SCK CEN is developing MYRRHA, a large-scale Accelerator Driven System. MYRRHA shall be a subcritical nuclear reactor driven by a high-power linear proton accelerator, which sustains the nuclear reaction. In the initial phase, known as the MINERVA project, the goal is to demonstrate the high reliability requirements on the accelerator. The two primary end users of the MINERVA project are the Full Power Facility and the Proton Target Facility. In collaboration with SCK CEN, CERN studied and designed an extraction septum for the 100 MeV Proton Target Facility. Two distinct topologies have been evaluated magnetically and tracked particle simulations have been executed to validate the designs. A preferred low-power solution has been retained for a subsequent detailed design. A final magnetic verification to confirm the mechanical design requirements has been carried out. This has allowed to develop a detailed 3D mechanical design including all manufacturing tolerances required for subcontracting the magnet fabrication to the industry. This article covers the 2- and 3-dimensional magnetic modelling, the tracked particle simulations and the mechanical design of the septum magnet.
Paper: WEPB085
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPB085
About: Received: 28 May 2025 — Revised: 13 Oct 2025 — Accepted: 13 Oct 2025 — Issue date: 05 Nov 2025
WEPB086
Design of prototype magnets for FETS-FFA
1921
Fixed Field Alternating gradient accelerators (FFA) hold promise for pulsed high intensity applications. No such FFA has been constructed to date; therefore a prototype - the Front End Test Stand-FFA (FETS-FFA) has been pro- posed to explore the feasibility of using FFA technology for the next generation spallation neutron source, ISIS-II. A key component of this prototype is its main magnets, which must meet several critical requirements: maintaining zero chro- maticity during acceleration, offering tune point flexibility, and providing a large dynamic aperture. The selected lattice incorporates a doublet spiral magnet design for more flexi- ble operations in the tune space. The magnetic field profile is generated by distributed conductors wound over the pole face; a 3D analysis using OPERA software was conducted to evaluate the settings necessary to produce the desired field. The cell tune variation was found to be within ±0.0015 hor- izontally and ±0.002 vertically, for four different working tune points.
Paper: WEPB086
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPB086
About: Received: 28 May 2025 — Revised: 30 May 2025 — Accepted: 31 May 2025 — Issue date: 05 Nov 2025
WEPB087
Design of FFA magnet for the laser-hybrid accelerator for radiobiological applications (LhARA)
1925
LhARA, which stands for “Laser-hybrid Accelerator for Radiobiological Applications”, is a novel and flexible facil- ity dedicated to research in radiobiology. A proton beam of energy up to 15 MeV can be produced by a laser driven source, the beam then enters a Fixed Field Alternating (FFA) gradient accelerator for acceleration to produce a variable ex- traction energy between 15-127 MeV. To avoid uncontrolled beam loss, the operational tune was picked carefully to avoid resonances. The magnetic field must be adjusted to ensure that the tune stays at the same working point for different energy ranges. The FFA ring uses combined-function spiral magnets, which create a radial magnetic gradient through distributed conductors wrapped around the pole, each car- rying a different current. A three-dimensional study was carried out in OPERA 3D and the parameters of the magnet were optimized. The results showed that resonances up to fourth order were avoided for the entire range of acceleration for different operational energies entire range of acceleration and different operational energies.
Paper: WEPB087
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPB087
About: Received: 28 May 2025 — Revised: 02 Jun 2025 — Accepted: 03 Jun 2025 — Issue date: 05 Nov 2025
WEPM040
Improving the beam extraction efficiency from SPS to the North Area at CERN using octupole phase space folding technique
2058
The High Intensity ECN3 (HI-ECN3) project aims to increase the number of protons per pulse delivered to a new experimental facility in CERN’s North Area up to $\sim 4 \cdot 10^{19}$ per year. Such an upgrade requires the reduction of the beam loss at SPS electrostatic septum (ZS) by at least a factor of four, since the activation of this device is the main factor constraining transition to the higher beam intensity. In this work we demonstrate one of the possible solutions to this problem that relies on octupole assisted folding of the beam in phase space. Implementation of this technique allowed to significantly reduce the losses at the ZS whilst transferring the beam through the LSS2 line, which connects the SPS and the transfer lines in the North Area, without deteriorating the transmission.
Paper: WEPM040
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPM040
About: Received: 28 May 2025 — Revised: 04 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
WEPM044
Analysis of losses and emittance growth in the 2024 LHC run and correlation with Dynamic Aperture
2069
This paper presents observations collected during the LHC operation with proton beams in 2024. In particular, a systematic analysis of the beam and machine parameters along the run reveals that the emittance evolution at the LHC injection plateau and during collisions cannot be fully explained by Intra-Beam scattering, synchrotron radiation and electron cloud effects, thus indicating that some beam dynamics effects are missing in the models. During the collapse of the separation bumps, a significant drop in beam lifetime is observed due to the reduction of Dynamic Aperture as the separation reduces and the machine enters into a beam-beam dominated regime. The correlation of beam lifetime in operation and Dynamic Aperture in simulations is demonstrated. Furthermore, a strong correlation is identified between this lifetime reduction and the population of non-Gaussian tails in the transverse beam profiles. The paper also includes the observation of high-frequency power supply ripple in the beam spectrum.
Paper: WEPM044
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPM044
About: Received: 29 May 2025 — Revised: 02 Jun 2025 — Accepted: 02 Jun 2025 — Issue date: 05 Nov 2025
WEPM045
Luminosity modeling of the LHC operation and performance projections for HL-LHC
2073
The LHC luminosity model is a powerful tool for studying the evolution of beam and machine parameters during the LHC operation. The model includes important effects that are present in LHC operation such as Intra-Beam Scattering, synchrotron radiation and burn-off. By comparing model predictions with experimental data, the presence of additional emittance blow-up and intensity loss mechanisms can be identified and then further studied. Using this model for comparing different configurations such as optics, filling schemes and beam types, allows identifying the best strategy to be adopted in operation to maximize integrated luminosity. In this contribution, we show the benchmarking of this model with data from the presently ongoing LHC Run 3, and its application to predicting the integrated luminosity for its future High-Luminosity LHC upgrade.
Paper: WEPM045
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPM045
About: Received: 29 May 2025 — Revised: 01 Jun 2025 — Accepted: 02 Jun 2025 — Issue date: 05 Nov 2025
WEPM048
Demonstrating beam splitting through stable islands formed by the third-order resonance at the CERN Super Proton Synchrotron
2085
In recent years, several new beam manipulation techniques have been proposed that exploit the crossing of nonlinear resonances and the use of stable islands of the transverse phase space. One such manipulation is a novel approach to slow extraction, which combines particle trapping in stable islands with the use of bent crystals to reduce losses on the extraction septum. As a first step towards testing this approach, measurements were performed at the CERN Super Proton Synchrotron (SPS) to demonstrate beam splitting using stable islands of the third-order resonance generated and controlled by sextupole and octupole magnets. The phase-space topology was reconstructed by displacing the beam and observing the turn-by-turn evolution of the signal of the beam position monitors. The beam splitting was achieved by varying both the machine tune and the radial steering of the beam. The measurement results were found to be in excellent agreement with the tracking simulations.
Paper: WEPM048
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPM048
About: Received: 19 May 2025 — Revised: 31 May 2025 — Accepted: 01 Jun 2025 — Issue date: 05 Nov 2025
WEPM095
Transverse coherent direct space charge: comparison between several approaches
2199
The proton driver of a future Muon Collider complex is designed to deliver a multi-GeV, short and high-intensity proton bunch to a target in order to maximize the muon yield. In the International Muon Collider Collaboration (IMCC), two high power H- Linac configurations are studied: a 2 MW with a beam energy of 5 GeV, and a 4 MW with a beam energy of 10 GeV. The Linac is followed by an accumulator ring and a compressor ring. With a single bunch intensity of 5.0e14 protons within a transverse emittance of ~15 mm mrad, strong space-charge effects can be expected in these rings. In this framework, different simulation codes used to estimate the transverse coherent space-charge mode frequency shifts in synchrotrons have been compared: BimBim, based on the Circulant Matrix Model (CMM); the Effective impedance method for space-charge; GALACTIC based on the Vlasov equation; the boxcar model for space-charge only; and the ABS model which assumes an Air-Bag bunch distribution in a Square well.
Paper: WEPM095
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPM095
About: Received: 29 May 2025 — Revised: 02 Jun 2025 — Accepted: 02 Jun 2025 — Issue date: 05 Nov 2025
WEPM108
Towards operational optics measurements with AC Dipole excitations in the CERN SPS
2225
In the CERN Super Proton Synchrotron (SPS), a new AC dipole excitation functionality has been implemented with the aid of the Beam-Based Feedback and Diagnostic Systems. This feature facilitates precise and systematic optics measurements, presenting a robust alternative to the conventional single-kick excitation method. Comparative studies of AC dipole and single-kick excitations have been performed, employing linear and nonlinear optics measurements. Experimental results highlight the reliability and accuracy of the AC dipole implementation, underscoring its potential for integration in standard SPS operations for routine optics measurements.
Paper: WEPM108
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPM108
About: Received: 26 May 2025 — Revised: 02 Jun 2025 — Accepted: 02 Jun 2025 — Issue date: 05 Nov 2025
WEPS015
Simulation of electron beam transport through the coherent electron cooling amplification section using real number of electrons
2271
Coherent electron cooling plays an important role in the Electron Ion Collider (EIC) by providing a fast cooling rate at collision energy to counter the emittance growth driven by intrabeam scattering effects. In this paper, we report on the high-fidelity simulation of the electron beam transport through the amplification section of the cooling channel. We will show the amplification of the initial modulation in the electron beam from the protons and present the study of collective effects such as the space-charge and CSR effects on the process of modulation amplification.
Paper: WEPS015
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPS015
About: Received: 20 May 2025 — Revised: 31 May 2025 — Accepted: 31 May 2025 — Issue date: 05 Nov 2025
WEPS028
Quadrupole pumping for bunch shortening in the Proton Synchrotron and Super Proton Synchrotron at CERN
2302
Quadrupole pumping is a longitudinal manipulation technique for bunch shortening, which works by modulating the RF voltage at twice the synchrotron frequency to excite bunch length oscillations. These controlled oscillations rotate the bunch in longitudinal phase space, with extraction set for when the bunch is shortest. Higher RF harmonics can also be used to linearise the synchrotron frequency distribution, reducing the formation of tails. Recently, quadrupole pumping has been proposed as a method for achieving ultra short bunches for proton-driven plasma wakefield accelerators such as the AWAKE experiment. In this contribution, we assess the performance of quadrupole pumping for the first time in the Proton Synchrotron (PS) and Super Proton Synchrotron (SPS) at CERN. Using simulations and beam measurements, we compare the effectiveness of this technique (without linearisation) against other bunch-shortening methods, including the unstable phase jump and the non-adiabatic voltage jump.
Paper: WEPS028
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPS028
About: Received: 27 May 2025 — Revised: 03 Jun 2025 — Accepted: 03 Jun 2025 — Issue date: 05 Nov 2025
WEPS035
Characterizing proton beam properties for cell irradiation study using GEANT4 simulation
2314
The purpose of this research is to characterize proton beam properties - beam energy, energy spread, beam size, and transverse emittance - to establish the initial setup for simulation in planning cancer cell culture experiments at the Cyclotron Medical Accelerator at King Chulalongkorn Memorial Hospital in Bangkok, Thailand. The characterization was performed using GEANT4 Monte Carlo (MC) simulations. Proton energies of 70 MeV, 100 MeV, 150 MeV, and 220 MeV were selected, and the 80%-20% distal fall-off of the depth profile was utilized to determine the energy spread. The simulated results were then verified against experimental data and compared with the Treatment Planning System (TPS). The details of the validating procedure, as well as results on the optimized energy spread, beam size, and emittance, and the irradiated setup for cell irradiation, will be discussed in this contribution.
Paper: WEPS035
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPS035
About: Received: 26 May 2025 — Revised: 30 May 2025 — Accepted: 30 May 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
THPB017
Magnetohydrodynamic effects in liquid lead target concept for Muon Colliders
2536
The use of liquid lead as a target material in particle accelerators is of significant interest due to its high density, high thermal power absorption capacity, and resistance to radiation damage. This makes it particularly well-suited for the high-intensity proton beams being studied for CERN’s Muon Collider proposal, with powers ranging up to 4 MW. To minimize shock propagation and manage the intense thermal and mechanical stresses induced by the high-power proton beam, a free-falling liquid lead curtain is explored as a promising concept. However, the target region requires strong magnetic fields, around 20 T, to re-focus the secondary particles generated at the target, introducing complex magnetohydrodynamic (MHD) effects in the liquid metal flow. These effects, particularly caused by Lorentz forces and MHD losses, present challenges to achieving stable and efficient high-power target systems. This work presents multiphase MHD simulations that reveal flow instabilities and highlight potential concerns within the free-falling curtain concept. The findings provide critical insights into the feasibility of liquid lead targets for high-intensity beams.
Paper: THPB017
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPB017
About: Received: 26 May 2025 — Revised: 31 May 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
THPB028
Non-destructive & destructive testing on accelerator’s components and materials at the European Spallation Source
2568
The European Spallation Source - ESS, has achieved its major construction in Lund, Sweden and is currently continuing in parallel the commissioning of its first systems. ESS aims to install and commission the most powerful proton LINear ACcelerator (LINAC) designed for neutron production and a 5MW Target system for the production of pulsed neutrons from spallation. In support of this ambitious goal, the Mechanical Measurements Lab (MML) at ESS provides an array of investigative solutions such as Resonant Ultrasound Spectroscopy (RUS), Transient Grating Spectroscopy (TGS), Modal Analysis, Structural Health Monitoring (SHM), Strain and Stress Analysis and Destructive Testing, guaranteeing full support to all the groups that have the mandate to install all the different components of the machine. The scope of this contribution is to describe the current status of the undergoing studies, together with the applied methodology and the definition of the testing apparatuses.
Paper: THPB028
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPB028
About: Received: 28 May 2025 — Revised: 04 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
THPB053
Compiling a life cycle inventory of a large accelerator facility: The ISIS-II neutron and muon source life cycle assessment
2620
The ISIS-II Neutron and Muon Source, the proposed successor to the ISIS Neutron and Muon Source at the Rutherford Appleton Laboratory, UK, presents a unique opportunity to integrate environmental sustainability practises from its inception. A Life Cycle Assessment (LCA) was performed during the early feasibility and design stage to evaluate the potential environmental impacts across construction, operation, and decommissioning phases, and to identify opportunities for impact reduction. With many accelerator components, elements and systems still in early optioneering stages, numerous assumptions were required to model the facility. This work explores these assumptions and the use of a simplified LCA framework, focusing on bulk material selection, future operational resource management, and strategies for managing non-radioactive and radioactive materials at decommissioning. Updated results of the LCA and identified strategies to minimize and mitigate negative environmental impacts are presented, emphasizing the role of LCAs in embedding sustainability into decision-making for large-scale scientific facilities.
Paper: THPB053
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPB053
About: Received: 28 May 2025 — Revised: 31 May 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
THPM007
Time-varying Bayesian optimisation for continual optimal injection in the CERN PS Booster
2695
The Proton Synchrotron Booster (PSB) receives 160 MeV H- ions, which are converted to protons at injection via a charge exchange mechanism, an upgrade that allows the production of low-loss high-intensity beams (> 10^13 per ring). To mitigate losses due to space charge, horizontal phase-space painting is performed with a system of fours kickers whose pulse is customisable via time and amplitude parameters. Recent work has shown that classical optimisation algorithms can find the optimal parameter values on both a digital twin and the real machine. However, these techniques: do not handle system-state time variations, do not continually update the parameters during operation, require non-negligible dedicated beam time and are usually not robust to observation noise. We suggest time-varying Bayesian optimisation and show that it addresses each of the previous issues at low development and deployment cost. This work improves the operation of the PSB and contributes towards the goal of automating the operation of particle accelerators.
Paper: THPM007
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPM007
About: Received: 19 May 2025 — Revised: 02 Jun 2025 — Accepted: 03 Jun 2025 — Issue date: 05 Nov 2025
THPM009
Model-based optimisation for automated multi-turn extraction tuning at the CERN Proton Synchrotron
2703
Multi-Turn Extraction (MTE) is a resonance-based technique employed in the CERN Proton Synchrotron (PS) to split the beam in horizontal phase space before extraction to the Super Proton Synchrotron (SPS). The splitting efficiency is evaluated based on the uniformity of intensities across the beamlets, requiring fine-tuning of multiple parameters. In this paper, we investigate the influence of key parameters on MTE efficiency to improve the understanding of their impact on the process. Using a Gaussian Process model and various visualization techniques, we assess the sensitivity of the MTE efficiency to horizontal tune, transverse feedback gain, excitation frequency, beam intensity and magnetic hysteresis. Results from experiments and simulations indicate a complex, non-convex relationship between MTE performance and the parameters listed above. Additionally, external factors such as thermal fluctuations may contribute to performance variability. Our findings highlight the need for a model-based controller to counteract parameter drift, thereby ensuring consistent MTE beam quality during operation. We propose a solution supported by experimental results.
Paper: THPM009
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPM009
About: Received: 26 May 2025 — Revised: 30 May 2025 — Accepted: 01 Jun 2025 — Issue date: 05 Nov 2025
THPM012
Optimizing collimator positions using bayesian optimization in the Fermilab MI-8 transfer line
2711
Collimators are used to minimize losses and to remove particles that would otherwise get lost downstream and irradiate the machine. Finding the optimal jaw positions is time consuming and with the upstream beam properties changing, the collimation settings would need to be readjusted each time. Therefore, a method to optimize collimator positions and to operate them at full capacity in a short time is required for loss control downstream. A study of collimator positions was conducted and a machine learning (ML) model was developed to predict optimal collimator positions. Bayesian Optimization (BO) was used to calculate new jaw positions from the ML model. The results of BO and usage of ML for better performance of the collimation system are presented in this paper.
Paper: THPM012
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPM012
About: Received: 29 May 2025 — Revised: 01 Jun 2025 — Accepted: 01 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
THPM101
Unified differentiable digital twin for the IOTA/FAST facility
2901
As the design complexity of modern accelerators grows, there is more interest in using advanced simulations that have fast execution time or produce insights about accelerator state. One notable example of additional information are gradients of physical observables with respect to design parameters produced by differentiable simulations. The IOTA/FAST facility has recently begun a program to implement and experimentally validate a unified start-to-end differentiable digital twin to serve as a virtual accelerator test stand, allowing for rapid prototyping of new software and experiments with minimal beam time costs. In this contribution we will discuss our plans and progress. Specifically, we will cover the selection and benchmarking of both physics and ML codes, the development of generic interfaces between device models and surrogate or physics-based sections, and the export of the parameters through either a deterministic event loop or a fully asynchronous EPICS soft input/output controller. We will also discuss challenges in model calibration and uncertainty quantification, as well as future plans to support larger proton accelerators like PIPII and Booster.
Paper: THPM101
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPM101
About: Received: 29 May 2025 — Revised: 04 Jun 2025 — Accepted: 04 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
THPM120
Application of large language models for the extraction of information from particle accelerator technical documentation
2935
The large set of technical documentation of legacy accelerator systems, coupled with the retirement of experienced personnel, underscores the urgent need for efficient methods to preserve and transfer specialized knowledge. This paper explores the application of large language models (LLMs), to automate and enhance the extraction of information from particle accelerator technical documents. By exploiting LLMs, we aim to address the challenges of knowledge retention, enabling the retrieval of domain expertise embedded in legacy documentation. We present initial results of adapting LLMs to this specialized domain. Our evaluation demonstrates the effectiveness of LLMs in extracting, summarizing, and organizing knowledge, significantly reducing the risk of losing valuable insights as personnel retire. Furthermore, we discuss the limitations of current LLMs, such as interpretability and handling of rare domain-specific terms, and propose strategies for improvement. This work highlights the potential of LLMs to play a pivotal role in preserving institutional knowledge and ensuring continuity in highly specialized fields.
Paper: THPM120
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPM120
About: Received: 21 May 2025 — Revised: 04 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
THPS024
Radiation monitoring and R2E performance in the LHC during the 2024 proton run
3006
The integrated luminosities in each of the ATLAS and CMS experiments at the Large Hadron Collider (LHC) have reached above 120 fb-1 during the proton run of 2024, the highest annual values since the beginning of the LHC operation. The same is true for LHCb, with over 10 fb-1 of integrated luminosity reached during proton operation in 2024. Such high levels of integrated luminosity are associated with high levels of radiation around the experiment locations, including hundreds of meters of tunnel on both sides of the interaction point, where beam losses driven by the luminosity production still occur. The ability of the LHC systems to operate in the radiation environment of the machine is analyzed in this contribution. Each year, radiation effects on electronic components installed around the LHC lead to premature beam dumps, causing accelerator down-time and loss of physics production. The number of radiation-induced beam dumps of the proton run 2024 per integrated luminosity has been comparable to previous years in LHC Run 3, and improved compared to LHC Run 2. However, due to the large integrated luminosity of LHCb, a large part of the events have been observed there, and some mitigation strategies to minimize such events are discussed.
Paper: THPS024
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPS024
About: Received: 27 May 2025 — Revised: 02 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
THPS083
Investigating beam-induced electron emission from thin wires in PSI proton beams
3133
The emission of electrons induced by beam interaction with thin targets is a phenomenon used to measure various properties of particle beams. The main processes of electron emission are: secondary emission, delta electron production and thermionic emission. The last one is not desired, because the intensity of thermionic electrons is not directly related to beam density profile. A common technique to suppress thermionic emission employs bias potential on the wire, which allows for recapturing of low energy electrons. This study investigates the effectiveness of the bias voltage method for high-brightness proton beams of the HIPA accelerator. Through experiments and simulations, the study aims to better understand the emission spectra, the suppression of thermionic emission, and the effects of beam fields on electron dynamics.
Paper: THPS083
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPS083
About: Received: 28 May 2025 — Revised: 04 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
THPS084
LHC BLM-based beam loss pattern recognition algorithm for off-momentum losses
3137
The Beam Loss Monitoring System (BLM) of the Large Hadron Collider (LHC) protects the accelerator against energy deposition from beam losses. One of the most critical moments regarding beam losses is the start of the beam acceleration. During this process, particles outside the bucket will not be captured in the first seconds of the start of ramp thus being lost at the machine aperture. This is expected to be the moment of minimum beam lifetime in the LHC cycle. During Run 3, losses from these off-momentum particles triggered some beam dumps. Several studies are on-going to assess a possible limitation from this loss scenario. This contribution quantifies the beam power lost at that moment and how the losses are distributed along the accelerator by the use of a dedicated BLM loss pattern recognition algorithm.
Paper: THPS084
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPS084
About: Received: 28 May 2025 — Revised: 31 May 2025 — Accepted: 01 Jun 2025 — Issue date: 05 Nov 2025
THPS087
Raspberry Pi cameras for beam diagnostics at the Frankfurt Neutron Source
3141
The application of Raspberry Pi cameras as cost-effective, versatile beam diagnostic tools is currently being explored at the Frankfurt Neutron Source (FRANZ). These compact imaging systems have been deployed to investigate proton beams at energies of 60 keV and 700 keV, including configurations where cameras are installed both externally and directly inside the accelerator’s RF resonator. Such setups provide opportunities to visualize beam profiles and related phenomena, potentially offering new insights into beam dynamics and cavity conditioning. This contribution will present the latest developments in camera integration, image acquisition, and preliminary image analysis techniques. By showcasing ongoing work and recent findings, we aim to highlight the potential of this approach for enhancing beam diagnostics in future accelerator environments.
Paper: THPS087
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPS087
About: Received: 28 May 2025 — Revised: 01 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
FRXD1
Neutron target for high-intensity operation at J-PARC MLF
3245
Neutron target for high-intensity operation at J-PARC MLF
Paper: FRXD1
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-FRXD1
About: Received: 31 May 2025 — Revised: 03 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025