target
MOZD2
Status of the baseline design for a 10 TeV muon collider
36
The muon collider concept promises a unique opportunity to push the energy frontier in particle physics. The large muon mass suppresses synchrotron radiation and allows the acceleration and collision of the beams in rings and the use of technology more similar to hadron colliders. Muons are point-like, in contrast to protons, and thus can achieve a similar physics reach with less energy, allowing for a more compact machine. However muons have a lifetime of only 2.2 microseconds at rest. The muon beam thus needs to be cooled and accelerated rapidly to maximise the luminosity, which creates several technology challenges. The International Muon Collider Collaboration is implementing an intense R&D programme to address these challenges and to develop the concept maturity. The presentation will highlight the key challenges, summarise the progress of the work and the proposed R&D plan for the next decade. Also initial studies of possible sites are included.
Paper: MOZD2
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOZD2
About: Received: 28 May 2025 — Revised: 04 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
MOPM010
Emittance tuning of the FCC-ee high energy booster ring
286
The Future Circular Collider (FCC), in its leptonic configuration has been chosen by CERN as main proposition for the next high-energy collider. This project aims to achieve luminosities one to two orders of magnitude higher than ever. Feasibility studies have led to the definition of tolerances on magnet imperfections and correction strategies. This is crucial for ensuring the performance of one of the main elements of the acceleration chain, the High Energy Booster (HEB) ring. The efficiency and overall performance of these strategies greatly influence new magnet specifications and tolerances, affecting main optic functions. Horizontal and vertical orbit corrections use horizontal and vertical kickers, respectively. Skew quadrupoles address vertical dispersion and transverse coupling. Normal quadrupoles correct the horizontal and vertical phase advances. This study simulates the distribution of these four corrector types to minimize the equilibrium emittance at the extraction energy of 45.6 GeV. The calculated strengths of these correctors and the associated misalignments are presented. The study also discusses the limitations and drawbacks of the proposed correction strategy.
Paper: MOPM010
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPM010
About: Received: 29 May 2025 — Revised: 02 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
MOPM025
Advancing the feasibility study of the ALICE fixed-target experiment using crystal-assisted halo splitting with HL-LHC lead ion beams
346
The Large Hadron Collider (LHC) at CERN is the world’s most powerful particle accelerator, capable of colliding proton and lead ion beams at energies up to 7 ZTeV. ALICE, one of the LHC’s key experiments, is designed for studying heavy-ion collisions. A proposed fixed-target experiment within ALICE involves directing a portion of the beam halo, extracted using a bent crystal, onto an internal target positioned a few meters upstream of the detector. For proton beams, this configuration has already demonstrated effective particle flux delivery to the target while operating safely alongside standard beam-beam collisions. However, with lead ion beams, the beam halo comprises nuclei of varying charge, mass, and magnetic rigidity, posing additional operational challenges. This paper presents an analysis of the expected performance, based on multi-turn particle tracking simulations using a detailed LHC model.
Paper: MOPM025
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPM025
About: Received: 28 May 2025 — Revised: 05 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
MOPM052
Bayesian methods and differentiable models for optics studies at the ISOLDE facility
449
The Isotope mass Separator On-Line facility (ISOLDE) delivers a wide range of low-energy radioactive ion beams to its experimental users. To meet varying demands, the facility uses different target materials, ionization methods, and cooling/bunching techniques, with beam configurations potentially changing weekly. To model particle transport through the transfer lines, it is essential to reconstruct the beam's initial transverse phase space for each setup, achieved via quadrupole scan measurements. This work explores the application of Bayesian techniques and differentiable models to reduce the time required to perform the beam setup.
Paper: MOPM052
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPM052
About: Received: 26 May 2025 — Revised: 02 Jun 2025 — Accepted: 03 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
MOPS011
Improvement on beam-based alignment methods by reliability weighted average technique
607
Accurate determination of magnet centres seen by beams is the key to a successful commissioning of a particle accelerator storage ring. In this paper, several techniques to improve the beam-based alignment for a circular accelerator storage ring are introduced. Firstly, a formula to propagate the uncertainties from linear fitting is given. Secondly, a reliability weighted averaging technique based on uncertainties are applied to mitigate the impact of outliers. Thirdly, studies show that the accuracy and precision of quadrupole centre locations can be refined by using multiple corrector magnets in the process. Finally, to improve the efficiency when using multiple correctors, a monte-carlo technique is utilized. The resulting distributions of all BPM-to-Quad offset residuals derived from simulations are presented.
Paper: MOPS011
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPS011
About: Received: 27 May 2025 — Revised: 31 May 2025 — Accepted: 01 Jun 2025 — Issue date: 05 Nov 2025
MOPS018
Demonstrating the feasibility of a double-crystal fixed-target experimental physics setup through the TWOCRYST project in the LHC
627
The TWOCRYST proof-of-principle experiment at the LHC is an initiative to demonstrate the feasibility of a double-crystal setup for fixed-target physics experiments. Such a setup could enable spin precession studies of charmed baryons in the TeV energy range in the HL-LHC era. Major milestones in this project have recently been achieved, including the successful construction and testing of critical components such as the 4~mm and 7~cm long bent silicon crystals required, a new combined fixed-target and crystal goniometer for accurate angular positioning, and two Roman pot stations equipped with advanced tracking detectors. This contribution summarizes the status of the hardware, the results from the first machine development studies to prepare for the measurements with the crystals in 2025, and a detailed plan for the beam tests with the full TWOCRYST setup.
Paper: MOPS018
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPS018
About: Received: 19 May 2025 — Revised: 03 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
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
MOPS020
The TWOCRYST fibre tracker: A detector to characterize precession crystals at the LHC
635
A fixed-target experiment using two bent crystals is proposed to study the magnetic and electric dipole moments of short-lived charm baryons with unprecedented precision in the LHC. This will be achieved exploiting crystal channeling into a first crystal to extract the beam halo and then into a 7 cm long silicon crystal capable of inducing a measurable spin precession to the particles of interest. TWOCRYST is a proof-of-principle machine test scheduled for 2025, to test this setup and address the feasibility of the final experiment under LHC beam conditions. One main goal is the study of the channeling efficiency in this long crystal at TeV energies, requiring a 2D detector in movable Roman pots. The TWOCRYST Fibre Tracker, coming from the LHC's ATLAS-ALFA experiment, is a high-precision tracking detector with ten layers of crossing scintillating fibers coupled to multi-anode photomultipliers, and read out using compact front-end electronics. Intense refurbishment work was required on to adapt the detector to the purposes of TWOCRYST. This contribution summarizes the tracker specifications as derived from beam dynamics simulations and the results of tests prior to its installation.
Paper: MOPS020
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-MOPS020
About: Received: 20 May 2025 — Revised: 30 May 2025 — Accepted: 30 May 2025 — Issue date: 05 Nov 2025
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
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
TUBN3
Exceeding high-luminosity LHC performance targets during the 2024 Pb-Pb ion run
899
We review the 2024 Pb-Pb ion run at the Large Hadron Collider (LHC), in terms of the operational experience, the problems encountered and the main results. This run was the second heavy-ion physics period of LHC Run 3 at 6.8 Z TeV. With only 18 days scheduled for physics data-taking, the key objective was to address the problems encountered in the 2023 Pb-Pb run and establish stable and efficient operation. Thanks to several mitigation measures, the 2023 limitations were overcome, significantly improving the machine availability. Together with substantially higher intensity, thanks to the excellent performance of the Pb ion injectors, this paved the way for a record-high performance in terms of average daily integrated luminosity with ion beams at the LHC.
Paper: TUBN3
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUBN3
About: Received: 15 May 2025 — Revised: 01 Jun 2025 — Accepted: 02 Jun 2025 — Issue date: 05 Nov 2025
TUCN2
Engineering magnetic carbon nanotubes via swift heavy ion irradiation for spintronics and quantum technologies: XAS and RAMAN study
925
Carbon nanotubes (CNTs), known for their versatility as 2D materials, are key to advancing quantum technologies such as qubit fabrication and magnetic data storage. In this study, multi-walled carbon nanotubes (MWCNTs) doped with magnetic impurities (Fe and Co) were exposed to swift heavy ion (SHI) irradiation to explore induced structural modifications. SHI beams transfer energy to the carbon matrix via electronic energy loss and thermal spikes, causing Fe and Co ions to agglomerate within interstitial regions and defect sites of the CNT matrix. Structural changes were analyzed using high-resolution X-ray diffraction (HRXRD), Raman spectroscopy, and near-edge X-ray absorption fine structure (NEXAFS). HRXRD revealed peak dissolution, reduced crystallinity, and increased lattice strain, while Raman spectra showed partial annealing of damaged CNTs with disorder parameter reduction (FeCNT: 0.65→0.57; CoCNT: 0.55→0.52). NEXAFS confirmed non-destructive processing. These findings link ion fluence with defect engineering, paving the way for magnetic CNTs in spintronics and data storage.
Paper: TUCN2
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUCN2
About: Received: 11 Jun 2025 — Revised: 12 Jun 2025 — Accepted: 14 Jun 2025 — Issue date: 05 Nov 2025
TUCN3
Commissioning of the South African Isotope Facility
928
The South African Isotope Facility (SAIF) is a radioisotope production facility based around a 70 MeV Cyclotron from IBA. SAIF was commissioned at the end of 2023 and commenced commercial isotope production in 2024. The facility is located in three vaults at iThemba LABS in Cape Town. The vault design, radiation modelling, and an overview of construction are presented. The designs and commissioning of the cyclotron, beam lines, wobbler magnet, dedicated target stations and target transport system are described and discussed, along with their current performance.
Paper: TUCN3
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUCN3
About: Received: 28 May 2025 — Revised: 31 May 2025 — Accepted: 31 May 2025 — Issue date: 05 Nov 2025
TUPB009
The latest design for a future short-baseline neutrino beamline
960
The ENUBET and NuTAG projects propose the measurements of the $\nu_e$ and the $\nu_\mu$ cross sections at the relevant energies of Hyper-Kamiokande and DUNE. While ENUBET focuses on a fully instrumented decay tunnel to achieve a precise flux measurement, NuTAG proposes the use of silicon-pixel detectors to achieve the \textit{full tagging} of the parent meson and the daughter lepton. Both ideas have merged into the Physics Beyond Colliders (PBC) Short-Baseline Neutrino (SBN) beamline study, supported through the PBC initiative at CERN. If deployed at CERN, the SBN beamline would need to be compatible with the operation of the current injector complex including the new SHiP experiment, in particular with respect to the number of protons required. The beamline's intensity requirement must therefore be kept at a minimum. With that in mind, a full optimization of the beamline was conducted to maximize the production of hadrons while fulfilling pile-up and background constraints. This contribution presents the optimized beamline design, elaborating on the techniques used and challenges faced during the design process.
Paper: TUPB009
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB009
About: Received: 23 May 2025 — Revised: 02 Jun 2025 — Accepted: 02 Jun 2025 — Issue date: 05 Nov 2025
TUPB018
Towards tailored beam distributions for fixed target experiments at CERN
987
The time-of-flight (nTOF) facility at CERN uses neutrons produced by a proton beam interacting with a fixed target. To prevent target damage, an upper bound on the peak energy density has been imposed. Adhering to this constraint requires a large beam size. Similarly, at CERN’s North Area, a large beam size is required at the septa splitting the beam towards different experiments. However, both cases suffer from limitations associated to losses of the primary beam, leading to poor transmission efficiency and high radioactive activation. This paper proposes an alternative approach by manipulating the beam distribution. Given the absence of strong nonlinear elements in both transfer lines, the focus shifts to tailoring the distribution before extraction. Particle tracking simulations are presented alongside experimental results, characterizing the phase space distribution as a function of machine parameters. Advanced deep learning methods that enable efficient exploration of the parameter space are also discussed.
Paper: TUPB018
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB018
About: Received: 27 May 2025 — Revised: 30 May 2025 — Accepted: 30 May 2025 — Issue date: 05 Nov 2025
TUPB022
Reduction of beam loss at the fast extraction section in J-PARC MR
1002
At J-PARC MR, proton beams are supplied to the neutrino facility via fast extraction (FX). The beam power, which was 500 kW in 2021, reached 800 kW by June 2024, with further upgrades planned. This increase in power has led to a rise in beam loss in the FX section, necessitating countermeasures. Residual doses are high at positions where the FX beam orbit closely approaches the aperture, and the effectiveness of beam loss countermeasures is evaluated by changes in residual dose. By June 2024, residual doses were successfully reduced through adjustments to the beam optics. For further reduction of beam loss, in July 2024, the aperture was expanded at the most upstream position where the beam orbit is in close proximity to the aperture. This report discusses the achievements during subsequent FX operations and outlines plans for further improvements.
Paper: TUPB022
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB022
About: Received: 28 May 2025 — Revised: 03 Jun 2025 — Accepted: 04 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
TUPB026
Research and development study on nanobeam formation using laser-cooled ions for high-precision single-ion irradiation
1017
To realize high-precision single-ion irradiation or implantation, we have proposed a nanobeam formation scheme where single cold ions selectively separated from a two-component Coulomb crystal in a linear Paul trap (LPT) are accelerated to 100 keV and focused on the nanometer scale using electrostatic bipotential lenses. The entire process of laser cooling of trapped ions in the LPT, ion-selective ejection from the LPT, acceleration, and focusing in the lens system is investigated by detailed multiparticle tracking simulations to show the feasibility of ultralow-emittance nanobeam formation and ion focusing properties. According to the simulation results, the fabrication and commissioning of such a single-ion irradiation system are ongoing at Takasaki Institute for Advanced Quantum Science, National Institutes for Quantum Science and Technology toward the application of research and development of quantum materials and devices. We will discuss the simulation results on the behavior of cold ions in the irradiation system and report the latest status of the system development including preliminary experimental results.
Paper: TUPB026
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB026
About: Received: 26 May 2025 — Revised: 31 May 2025 — Accepted: 13 Oct 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
TUPB034
Status of the pulsed hydrogen gas stripper project at GSI
1044
The operation of the specifically upgraded pulsed gas stripper development setup for the user beamtime lasted until July 2024. It was very successful in terms of both providing stripped ions and gaining valuable experience in the long-term operation of the pulsed stripper. The long periods of high duty nitrogen operation revealed a severe service life issue of the fast injection valves, which was already anticipated in the risk assessment for the hydrogen operation. This emphasizes the need for the safety measures incorporated in the design of the pulsed stripper facility. During the user beamtime, several measurement campaigns were conducted. Extensive data on the stripping efficiencies for 12 projectile-target combinations could be obtained. In this contribution the obtained results and lessons learned are presentet as well as the necessary next steps to finaly bring the hydrogen stripping to routine operation.
Paper: TUPB034
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB034
About: Received: 27 May 2025 — Revised: 30 May 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
TUPB037
New linac designs by High Energy Sources R&D Group at Varex Imaging
1050
High Energy Sources R&D group at Varex Imaging has developed several Accelerator Beam Centerline (ABC) and Linear Accelerator (linac) designs in the past 8 years. Here we present a summary of our recent progress. M9V linac, featuring our new ABC, is being developed to further improve characteristics of 9 MeV accelerator. The new ABC is shorter than the standard 9 MeV linac, and the focusing solenoid is completely removed. The overall system design increases dose rate and reduces the weight and complexity. In addition, our new version of K15, called K15V or V15, is being redesigned with a hybrid Standing Wave (SW) and Traveling Wave (TW) reverse feed configuration, protected by US patent. We expect it to produce significantly higher dose rate of up to 40000 R/min at 1 m. The first SW section of this linac may be used separately in 9 MeV system we called V9, which is also expected to deliver higher dose rate of up to 20000 R/min while substantially reducing neutron yield compared to 15 MeV machine. We have also tested a new concept implemented on 6 MeV linac, which permitted reducing the electron beam focal spot size to 350±150 µm without utilization of any magnetic systems.
Paper: TUPB037
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB037
About: Received: 28 May 2025 — Revised: 13 Oct 2025 — Accepted: 13 Oct 2025 — Issue date: 05 Nov 2025
TUPB046
Design of a helium ion linear accelerator for astatine production
1067
Astatine 211 is one of the most effective theragnostics isotopes for targeted alpha therapy of cancer. Connected to a carrier that links to cancer cells when injected in a patient, this powerful alpha emitter can selectively destroy cancerous cells. Accelerator production of 211At requires sending beams of fully stripped helium ions (alpha particles) on a bismuth target at the energy of 7.1 Me/u. To obtain sufficient doses for hospital production of 211At, currents higher than what provided by cyclotrons are required. For this type of particle and intensities, cyclotrons are limited by the large amount of beam loss and activation in the extraction region, while linacs are virtually loss-free and much better suited for At production. The design of an innovative linac for At production is presented, based on an alpha particle source of new design, a compact Radio Frequency Quadrupole, and a Quasi-Alvarez Drift Tube Linac (QA-DTL) going up to the final energy. Thanks to the QA-DTL low injection energy and compact design, the linac is only 10 meters in length. The overall design is presented, together with detailed RF and beam optics simulations.
Paper: TUPB046
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB046
About: Received: 28 May 2025 — Revised: 05 Jun 2025 — Accepted: 13 Oct 2025 — Issue date: 05 Nov 2025
TUPB047
CERN-MEDICIS: A unique facility for the production of radionuclides for medical research
1071
The MEDICIS facility is a unique facility located at CERN, dedicated to the production of non-conventional radionuclides for research and development in imaging, diagnostics and radiation therapy, and based on offline mass separation. It exploits a classified area for handling of highly radioactive open sources, a dedicated isotope separator beam line, a target irradiation station at the 1.4 GeV Proton Synchroton Booster (PSB) and receives activated targets from external institutes during CERN Long Shut-Downs. After collection, the batch is prepared to be dispatched to a research center. Since its commissioning in December 2017, the facility has provided novel radionuclides such as Ba-128, Tb-155, Sm-153, Tm-165 Ra-224/Pb-212 and Ra-225/Ac-225 with high specific activity, some for the first time, to research institutes part of the collaboration. CERN-MEDICIS has advanced significantly to reach mature processes to translate into clinical application for the most promising radionuclides.
Paper: TUPB047
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB047
About: Received: 17 May 2025 — Revised: 02 Jun 2025 — Accepted: 04 Jun 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
TUPB052
Laser wakefield accelerator-driven photonuclear reactions for the production of medical radionuclide 67Cu
1086
Recent results of production of the medical radionuclides 67Cu using a laser wakefield accelerator (LWFA) are presented. This emerging technique utilises powerful, ultrashort laser pulses that are focussed into a gas jet to create a plasma wake that traps and accelerates electrons to very high energies with large accelerating gradients. Accelerated electrons interact with high-Z material to produce high-energy photons by bremsstrahlung, which then produce 67Cu via the 68Zn(γ, p)67Cu photonuclear reaction. 67Cu, with 62 h half-life, is considered ideal radioisotope for treatment of lymphoma and colon cancer.* The production of 67Cu requires medium-energy (~70 MeV) protons that are only available at limited number of facilities. We present the experimental setup, maximising electron pulse intensity by optimising laser beam properties and target composition of gas jet. The gamma beam and the design of 68Zn are optimised using FLUKA simulations. We will also report on the development of detectors for online monitoring of the electron and gamma beams, and produced activities of the radionuclides.
Paper: TUPB052
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB052
About: Received: 29 May 2025 — Revised: 04 Jun 2025 — Accepted: 06 Oct 2025 — Issue date: 05 Nov 2025
TUPB074
Status of J-PARC accelerator chain
1128
The Japan Proton Accelerator Research Complex supplies a high-intensity proton beams for the physics experimental programs in the Material and Life Science Facility (MLF), the Hadron experimental facility and the neutrino target. In such a high-intensity hadron accelerator, losing less than 0.1% of the beam can cause several problems. Such lost protons can cause serious radioactivation and accelerator component malfunctions. Therefore, we have been continuing a beam study to achieve high-power operation with enough smaller loss condition. In addition, we have also improved and maintained the accelerator components, enabling a stable operation. Through these efforts, we established a beam power of 1-MW operation for the MLF users and a beam power of 800-kW operation for the neutrino users. In this paper, Recent achievement is summarized.
Paper: TUPB074
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB074
About: Received: 29 May 2025 — Revised: 13 Oct 2025 — Accepted: 13 Oct 2025 — Issue date: 05 Nov 2025
TUPB100
Towards the detection of mixed helium and carbon ion beams using a gas-filled charge exchange cell
1151
Irradiation with mixed helium and carbon ion beams is emerging as a promising approach to treatment monitoring in ion radiotherapy. In contrast to mono-isotopic beams, the full characterization of the mixed beam requires distinguishing ion species of almost identical charge-to-mass ratio, which is not feasible with most conventional beam diagnostic devices. This proceeding proposes a measurement concept that could allow for determining the ion mixing ratio after extraction from the ion source at energies around 10 keV/u. The concept relies on a gas-filled charge exchange cell, where the traversing ions experience electron capture events, followed by an electrostatic or magnetic analyzer and beam intensity measurement. The proposal is accompanied by proof-of-concept measurements performed at the *Helmholtz Zentrum Dresden-Rossendorf (HZDR)*, which showcase the potential but also several challenges associated with the measurement concept.
Paper: TUPB100
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPB100
About: Received: 27 May 2025 — Revised: 01 Jun 2025 — Accepted: 05 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
TUPM092
Design studies on a kHz–MHz repetition rate pulsed muon source based on electron accelerator
1372
Certain types of muon experiments, such as muon spin rotation techniques and muon lifetime measurements, require beams with repetition rates around 50 kHz for optimal statistical performance. However, existing facilities are limited to pulsed beams operating at 25-50 Hz or continuous beams, both constrained by the time structure of proton drivers. Despite ongoing efforts to optimize these proton time structures, significant limitations in flexibility persist. This work introduces an alternative approach to muon production using high-repetition-rate (kHz-MHz) electron beams generated by superconducting linacs at XFEL facilities. This method provides unique temporal characteristics, promising substantial improvements in beam precision, flexibility, and experimental efficiency. We present comprehensive particle tracking simulations for the design of a surface muon beamline and detailed Monte Carlo studies to optimize target materials and geometries. The results underscore the potential of electron-driven muon sources to complement muon-based fundamental and applied physics research while extending the capabilities of current and future XFEL facilities.
Paper: TUPM092
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPM092
About: Received: 28 May 2025 — Revised: 02 Jun 2025 — Accepted: 03 Jun 2025 — Issue date: 05 Nov 2025
TUPS059
Novel deuteron accelerator for nuclear waste transmutation
1564
Accelerator-driven systems (ADSs) can accelerate high intensity ions to generate high flux of neutrons to transmute the long-lived species in used nuclear fuel (UNF) from nuclear reactors. A typical specification would be for a 1-2 GeV proton beam, comprising multi-MW-level power load on a spallation target. An alternative approach could be to produce the neutrons via breakup of 40-MeV deuterons on a low-Z target. For this purpose, an innovative deuteron cyclotron auto-resonance accelerator dCARA is described here. It is predicted to produce a 40-MeV, 125 mA CW deuteron beam, with notable features including continuous acceleration without bunching for good beam stability, high efficiency, wide beam aperture, and an exceptionally short length of 1.6 meters. It is estimated that 5-10 smaller ADS dCARA-based modules could provide the same level of transmutation as one ADS employing a GeV-level 25-MW linac. Other applications of dCARA include medical isotope production system, or fusion prototypic neutron source for testing inner-wall materials for a future fusion power reactor.
Paper: TUPS059
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPS059
About: Received: 28 May 2025 — Revised: 02 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
TUPS074
Packaged photocathodes for X-ray free electron lasers
1586
Alkali photocathodes are vital for generating high-performance electron beams in accelerator technologies, but their production remains challenging. Current in-house fabrication methods are complex, costly, and unreliable, limiting the potential of these materials for bright electron sources. Our innovative approach seeks to commodify photocathodes, offering a ready-to-use product for accelerator facilities and scientific institutions. We use a proprietary sputtering process with in-house-manufactured bulk targets, ensuring consistent quality and streamlined production. Unlike traditional vacuum suitcases, which are heavy and require active power, our photocathodes are stored in portable, palm-sized vacuum canisters that maintain vacuum without power. This design preserves their integrity during transport and handling, addressing their extreme sensitivity to air and moisture, which demands ultra-high vacuum protection. By delivering pre-fabricated, protected photocathodes, we eliminate the need for facilities to invest in specialized equipment, enabling broader adoption and reducing downtime. Our work paves the way for accessible, affordable, and readily available photocathodes.
Paper: TUPS074
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-TUPS074
About: Received: 31 May 2025 — Revised: 13 Oct 2025 — Accepted: 13 Oct 2025 — Issue date: 05 Nov 2025
WEPB050
Test coil-unit fabrication of Nb3Sn superconducting multipole wiggler for next generation light source in KEK-PF
1851
Recently, KEK PF has started developing a superconducting multipole wiggler (SC-MPW) for an application in next-generation light source ring. The SC-MPW is expected to be a key insertion device for the light utilization of a wide wavelength region by aiming at high-brightness and high-energy X-ray production while keeping the stored beam energy as low as 2.5 GeV. In addition, the short period length of multipole wiggler not only lowers the light spread and increases the effective photon flux, but also reduces the beam orbit amplitude, which leads to suppressing the emittance growth in a low emittance ring. In our application, the magnetic field more than 2.5 T is required on the central beam orbit even in a short period length less than 80 mm with a wide gap more than 30 mm that secures the beam orbit region. As we need to investigate the candidate of Nb3Sn wires and to study the coil-fabrication techniques which meet a use as multipole wiggler, PF has completed the first prototype-coil unit consisting of three poles and successfully conducted excitation tests at the low current. The detailed fabrication of test-coil unit and the prospects for high-current testing will be reported.
Paper: WEPB050
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPB050
About: Received: 25 May 2025 — Revised: 31 May 2025 — Accepted: 02 Jun 2025 — Issue date: 05 Nov 2025
WEPB056
Status of VPU development for PAL-XFEL
1865
PAL-XFEL is planning to install second hard X-ray undulator line (HX2) to meet the high beamtime demand from the users. The photon energy range for the second hard X-ray beam line is from 2~ to 11 keV which is lower than the first hard X-ray photon energy range (2 ~ 20 keV). The required undulator parameters are 35 mm period, max Keff=3.48 at 9.00 mm gap, ~ 3.0 m magnetic length with phase error less than 5 degrees. In addition to the existing conventional undulator design, horizontal gap vertical polarized undulator (HGVPU) concept is also being considered. HGVPU is well developed by LCLS-II team and applied in LCLS-II. In this report, we summarize the VPU design for PAL-XFEL HX2, and reports progress in the prototyping.
Paper: WEPB056
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPB056
About: Received: 29 May 2025 — Revised: 30 May 2025 — Accepted: 02 Jun 2025 — Issue date: 05 Nov 2025
WEPB065
Development of compact ultra-high power pulsed power supply
1893
Currently, pulsed power supply systems with output power of several GW, output voltage of several hundred kV, and pulse width of 100 ns are difficult to miniaturize and portability is a limitation for industrial applications. We are developing a pulsed power supply with an output power of 4 GW, an output voltage of 200 kV, and a pulse width of 100 ns, which is 1/20th the mass of conventional products, in order to solve this limitation. In this presentation, we will give an overview of the system design and the current status of the development.
Paper: WEPB065
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPB065
About: Received: 27 May 2025 — Revised: 02 Jun 2025 — Accepted: 02 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
WEPS018
Bunch length regulation in the LHC during controlled emittance blow-up
2279
Controlled longitudinal emittance blow-up is indispensable for the operation of the Large Hadron Collider (LHC) to counteract single-bunch loss of Landau damping during the acceleration ramp. The blow-up is performed by injecting RF phase noise in a narrow frequency band into the beam phase loop, with bunch-length feedback regulating the noise amplitude. In 2024, the variation of the bunch length due to imperfect regulation caused unacceptable beam-induced heating of certain accelerator components. In this contribution, we present the results of extensive simulation scans that have been used to optimize the feedback parameters. We show how this optimization, along with a reduction of the feedback delay on the controls side, has been implemented in the LHC and significantly improved the bunch length evolution during acceleration. Finally, we discuss the results of a measurement scan performed during an operational period of five weeks to fine-tune the blow-up feedback settings.
Paper: WEPS018
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPS018
About: Received: 26 May 2025 — Revised: 30 May 2025 — Accepted: 01 Jun 2025 — Issue date: 05 Nov 2025
WEPS023
Study for limiting factors in transverse wiggler-based arbitrary correlation generation
2294
Recently proposed transverse wiggler is an intriguing tool for imparting designed correlations in phase space. While several simulations have demonstrated its feasibility, the method using the transverse wiggler has several concerns need to be addressed. Beam evolution along the wiggler can introduce errors in the designed correlation. Wiggler fields have strong vertical position dependence, which can introduce unwanted horizontal and vertical couplings. The transverse wiggler generates both horizontal and vertical sinusoidal fields, which can significantly degrade the beam quality. Additionally, its applicability to heavy particles remains uncertain. We will present results from a preliminary study aimed at addressing these concerns.
Paper: WEPS023
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPS023
About: Received: 28 May 2025 — Revised: 30 May 2025 — Accepted: 01 Jun 2025 — Issue date: 05 Nov 2025
WEPS038
Python FLUKA beam line, a python library to create FLUKA simulations of accelerators
2321
FLUKA simulations of beamlines are important for un- derstanding numerous different aspects of accelerators, in- cluding beam losses, particle backgrounds, activation and shielding. Creating a beam-line simulation using FLUKA is a time consuming and potentially error prone process. This paper describes a set of python tools called pyflubl (Python FLUKA beam-line) which can create a FLUKA simulation using input from MAD-X, MAD8, Transport or BDSIM. pyflubl is based on multiple stable and advanced python packages created to make BDSIM (Geant4) beamline simu- lations as simple as possible, these are pymadx (an interface to MAD-X output), pymad8 (an interface to MAD8 out- put), pybdsim (interface to BDSIM) and most importantly pyg4ometry (a geometry engine for Monte Carlo geometry creation). The magnetic fields required for FLUKA are im- plemented in C++ via BDSIM, thus keeping fields consistent between Geant4 and FLUKA beamline simulations. This paper describes pyflubl design and implementation and ex- ample results for an idealised electron beam-line. Particular attention is given to geometry, fields and scoring.
Paper: WEPS038
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPS038
About: Received: 28 May 2025 — Revised: 05 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
WEPS147
R&D on SRF cavities at INFN-LASA
2462
As part of its ongoing and future contributions to high-Q/high-G activities in major international projects such as PIP-II, ILC Technology Network, and the European Strategy for Particle Physics, INFN-LASA is upgrading its experimental facility for vertical cold tests of superconducting cavities. This upgrade will enable cavity performance characterization in a low residual magnetic field environment and with dedicated diagnostics for understanding possible performance limitation. In parallel, state-of-the-art surface treatments aimed at achieving high-Q and high-G performance are being developed and applied to single and multicell cavities at different frequencies. This paper presents the current status of the facility, its key features, an overview of cavities currently in production, and the experimental results obtained to date.
Paper: WEPS147
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPS147
About: Received: 29 May 2025 — Revised: 13 Oct 2025 — Accepted: 13 Oct 2025 — Issue date: 05 Nov 2025
WEPS148
INFN LASA in-kind contribution to PIP-II
2466
This paper reports the status and recent progress of INFN LASA’s in-kind contribution to the PIP-II project at Fermilab, with updates on key activities and major procurements. Production efforts for the 38 INFN LASA-designed, 5-cell cavities (β=0.61) for the LB650 section of the linac are underway and two pre-series prototypes are being realized as a first step to validate the manufacturing and treatment sequence. Concurrently, preliminary testing on existing prototypes is progressing to gain a deeper understanding of the surface preparation and qualification procedures, including cross-validation at different infrastructures. Series LB650 cavities will be industrially produced and surface-treated to achieve the stringent performance targets, qualified via vertical cold tests at DESY AMTF, and delivered installation-ready for string assembly.
Paper: WEPS148
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-WEPS148
About: Received: 28 May 2025 — Revised: 13 Oct 2025 — Accepted: 13 Oct 2025 — Issue date: 05 Nov 2025
THPB008
Sputtering characteristics of a compact NEG-coating device and performance evaluation of the TiZrV thin films
2517
Non-evaporable Getter (NEG) coating is a breakthrough technology wherein the inner walls of a vacuum chamber are coated with a material that functions as a vacuum pump. This technology is expected to gain widespread adoption across various fields in the future. However, the current coating method, originally developed for long beam ducts, is not adaptable to a wide range of vacuum chamber designs. Therefore, we have developed a compact NEG coating device that can be adapted to chambers of various geometries. The primary advantage of this device is its ability to coat complex-shaped chambers, which was difficult with conventional methods. Additionally, by reducing the uncoated surfaces as much as possible, it significantly improves pumping performance in terms of pumping speed and reducing Photon Stimulated Desorption (PSD) yields. We explore the optimal sputtering conditions for depositing high-performance NEG thin films with the device, and have performance evaluations of the NEG films, with observing the morphologies, measuring the pumping speed and PSD yields.
Paper: THPB008
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPB008
About: Received: 28 May 2025 — Revised: 04 Jun 2025 — Accepted: 05 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
THPB050
Development of robust beam window by additive manufacturing
2609
Construction of the COMET experimental facility is underway to explore the muon-electron conversion process at the J-PARC Hadron facility. An 8 GeV proton beam supplied from the main ring irradiates a target in a superconducting capture solenoid magnet, and the produced pions and muons are transported to the experimental area. In the beam line, the muon transport solenoids are composed of superconducting magnets cooled by liquid Helium (LHe). The beam windows should be robust enough to withstand against rapid and high pressure increase in emergency of LHe quenching until rupture disks break. Simultaneously, the density of the beam window material must be low, and the thickness must be as thin as possible, while minimizing the beam energy loss for high transmission efficiency. Therefore, we have been developing a beam window built by additive manufacturing. We have successfully developed a beam window made of Ti-6Al-4V with a diameter of 269 mm, a thickness of 0.5 mm, and a proof pressure of 30 atm, and have now started development of a beam window made of AlSi10Mg. In this presentation, we will report on the development status of the beam window by additive manufacturing.
Paper: THPB050
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPB050
About: Received: 28 May 2025 — Revised: 02 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
THPB059
A helium-cooled target design for the SPS Beam Dump Facility (BDF) at CERN
2634
CERN’s upcoming SPS Beam Dump Facility (BDF) will host a production target designed to manage challenging thermal and mechanical conditions while providing the physics output required by the Search for Hidden Particles (SHiP) experiment. It must fully absorb 400 GeV/c protons and dissipate up to 305 kW. The baseline design consists of water-cooled tantalum-alloy clad TZM and tungsten (W) blocks. Challenges for the maintenance and reliability of the baseline design led to the development of alternative concepts. The leading design—a helium-cooled W target—optimizes thermal management and structural integrity while simplifying the manufacturing and improving its physics performance for the SHiP experiment. The experimental validation of this concept will be via testing multiple prototypes in an existing slow beam extraction test bench at CERN’s North Area. In parallel, extensive R&D is being pursued on: properties of pure W products including hot-rolled plates; manufacturing of seamless blocks; W-W diffusion bonding techniques. This contribution includes an overview of the helium-cooled target design and a summary of the ongoing material characterization, prototyping and beam-tests.
Paper: THPB059
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPB059
About: Received: 28 May 2025 — Revised: 05 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
THPB087
Overview of IFMIF-DONES lithium target system design
2654
At the core of IFMIF-DONES is placed the Target System. It generates a high-speed liquid lithium jet (15 m/s, 300°C) acting as the target for a 40 MeV, 125 mA deuterium-based linear accelerator, with the primary aim of qualifying fusion-related materials. The design of the Target System has evolved during the last few years addressing key challenges. Managing the 5 MW of power deposited continuously in the target requires a reliable lithium loop supplying liquid lithium in well-defined conditions. The extreme operational conditions, exposed to high irradiation levels (~25 dpa/year), demand also careful selection of materials and regular replacement strategies for critical components, supported by dedicated Remote Handling systems. Current efforts focus on optimizing the design to meet the requirements for its upcoming construction phase. This includes advanced features to facilitate assembly, installation, and long-term operability. Additionally, attention is being paid to the integration of diagnostics. This contribution highlights the recent R&D and engineering solutions aimed at advancing the Target System toward successful construction, commissioning and subsequent operation.
Paper: THPB087
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPB087
About: Received: 27 May 2025 — Revised: 03 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
THPB099
Design overview of the medium energy beam transport line for the ANTHEM project
2680
The ANTHEM (Advanced Technologies for Human-centered Medicine) research project will establish a Research and Clinical Center in Caserta, Italy, for the study and application of Boron Neutron Capture Therapy (BNCT). The Radio-Frequency Quadrupole (RFQ), designed by INFN, produces proton beam of 30 mA at 5 MeV, impinging on a beryllium target. A 12 m long Medium Energy Beam Transport (MEBT) line, located after the RFQ, is responsible for transporting the beam to the target for optimal neutron production. This paper gives an overview of the design of MEBT line and details its main characteristics about beam dynamics, vacuum system and its mechanical layout.
Paper: THPB099
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPB099
About: Received: 25 May 2025 — Revised: 14 Oct 2025 — Accepted: 14 Oct 2025 — Issue date: 05 Nov 2025
THPM095
Benchmarking of new approach for analyzing transverse beam emittance measurement
2882
A recent analysis of emittance measurements highlighted the limited reliability of tools for precise method evaluation and error calculations. In this paper, a new analysis method is presented with its associated errors calculations. It is evaluated using realistic beam simulations and compared to the linear regression method commonly referenced in the literature. This new analysis method is shown to be easier to implement and provides results with a good confidence interval.
Paper: THPM095
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPM095
About: Received: 22 May 2025 — Revised: 02 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
THPM113
Trajectory steering for DC beams at the CERN SPS using reinforcement learning based on intensity measurements
2928
The slow extracted beams at the CERN Super Proton Synchrotron (SPS) are transported over several 100 m long transfer lines to three targets in the CERN North Area Experimental Hall. The experiments need intensity fluctuations to be entirely eliminated over the roughly 5 s particle spill, requiring full debunching of the extracted beams. In this environment, secondary emission monitors (SEMs) have to replace the conventional beam position monitoring systems that rely on RF structure, with the intensity difference on split secondary emission foils used to indicate the beam position. Traditional trajectory correction algorithms however fail when the beam ends up on a single foil. This paper summarises successful first tests with reinforcement learning (RL) to learn to correct the trajectory based on foil intensity measurements. The RL agents were trained in simulation and then successfully transferred to the real accelerator environment. Results of the application of the trained RL agents for the alignment of moveable split foils in front of the targets will also be presented.
Paper: THPM113
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPM113
About: Received: 26 May 2025 — Revised: 02 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
THPM116
Efficient data-driven model predictive control for online accelerator tuning
2931
Reinforcement learning (RL) is a promising approach for the online control of complex, real-world systems, with recent success demonstrated in applications such as particle accelerator control. However, model-free RL algorithms often suffer from sample inefficiency, making training infeasible without access to high-fidelity simulations or extensive measurement data. This limitation poses a significant challenge for efficient real-world deployment. In this work, we explore data-driven model-predictive control (MPC) as a solution. Specifically, we employ Gaussian processes (GPs) to model the unknown transition functions in the real-world system, enabling safe exploration in the training process. We apply the GP-MPC framework to the transverse beam tuning task at the ARES accelerator, demonstrating its potential for efficient online training. This study showcases the feasibility of data-driven control strategies for accelerator applications, paving the way for more efficient and effective solutions in real-world scenarios.
Paper: THPM116
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPM116
About: Received: 27 May 2025 — Revised: 02 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
THPS011
Operational challenges of the SuperKEKB iBump feedback system
2968
To maintain optimal beam collision conditions and luminosity performance, SuperKEKB requires a fast orbit feedback dedicated to correcting offsets at the interaction point (IP). The 'iBump' feedback system calculates IP beam offset from Beam Position Monitor (BPM) measurements before and after collision and corrects by creating closed orbit bumps in the High Energy Ring (HER). This system has demonstrated robustness at stabilising IP offsets during operation. In this paper, we discuss operational aspects of the system and ongoing challenges, with a focus on the identification of vertical offset as the correction target of the iBump system. Dedicated studies on the current dependence of this feedback target as well as historical data are analysed.
Paper: THPS011
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPS011
About: Received: 26 May 2025 — Revised: 03 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
THPS017
Design and validation of a micrometric and adaptable calibration bench for frequency scanning interferometry sensors
2988
The High-Luminosity Large Hadron Collider (HL-LHC) project at CERN aims to enhance the LHC's performance and increase its discovery potential. As part of this upgrade, new components will be installed and must be aligned with an accuracy of 0.17 mm vertically and 0.33 mm radially (1σ) over a length of 420 m. To achieve such requirements in harsh conditions, CERN has developed a range of new sensors using Fourier analysis-based Frequency Scanning Interferometry (FSI), capable of absolute distance measurements on multiple targets within a few micrometers’ uncertainty. More than 600 of these FSI sensors will be deployed for the project, necessitating an accurate, fast, adaptative and cost-effective calibration of these sensors. To do so, a specialized calibration bench has been developed. This paper details the design, benchmarking, and final validation of this calibration bench, which enables rapid calibration of a wide range of FSI sensors to an accuracy below 10 μm (1σ). Additionally, it presents the first intense use of this bench in the frame of the Inner Triplet String test, a facility representing one complete section of new focusing regions of the HL-LHC upgrade project.
Paper: THPS017
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPS017
About: Received: 23 May 2025 — Revised: 05 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
THPS028
Reliability analysis of the new Universal Quench Detection System and Protection Devices Supervision Unit for the HL-LHC inner triplet magnets
3022
The new Universal Quench Detection System (UQDS) and Protection Devices Supervision Unit (PDSU) are pivotal elements for the quench protection system of the new HL-LHC inner triplet superconducting magnets as well as for requesting a beam dump upon activation of the active quench protection systems, the novel Coupling Loss Induced Quench System (CLIQ) and the traditional quench heaters (HDSs). Given the criticality of these functionalities, a thorough reliability analysis has been carried out to ensure that the probability of critical failures meets the stringent reliability requirements under all operational conditions. To determine the failure probabilities, analytical models were developed that consider redundancies, inspection strategies and demand frequencies. The models’ failure parameters were identified by a component-based Failure Mode, Effects and Criticality Analysis (FMECA). The results of the models allow the qualification of the system design as well as insights on critical monitoring and testing requirements of the system when in operation.
Paper: THPS028
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPS028
About: Received: 28 May 2025 — Revised: 03 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 05 Nov 2025
THPS047
Fully experiment request driven beta* and separation luminosity levelling at the LHC
3072
During the third run period (2022-2026) of the CERN Large Hadron Collider (LHC), as well as for the future High-Luminosity LHC era, luminosity levelling is key to control the event pile-up in the experiments as well as the heat load to the cryogenic system of the superconducting magnets close to the interaction points. During 2024 proton physics operation, a new luminosity levelling scheme was introduced for the high-luminosity experiments, ATLAS and CMS. Combining levelling by optical squeeze (beta*) with small transverse separation changes gives the beam stability benefits of beta* levelling (head-on tune spread and landau damping) while keeping the flexibility of separation levelling (independent levelling for each experiment in arbitrary steps of luminosity). This not only allowed each experiment to set their luminosity target independently, but also reduced the luminosity spread during levelling from 5%, when using just beta* levelling, to less than 3%, resulting in a more homogeneous data set.
Paper: THPS047
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPS047
About: Received: 22 May 2025 — Revised: 30 May 2025 — Accepted: 30 May 2025 — Issue date: 05 Nov 2025
THPS098
Enabling arbitrary correlations in beam phase space via curve matching
3166
Beam manipulations require precise control of phase space correlations. Gwanghui's previous work introduced a method for generating arbitrary correlations using Fourier series and cosine sums with transverse wigglers. However, accurately controlling the wigglers to match a desired correlation curve remains challenging, as it involves optimizing parameters like amplitude, phase, and period. Existing optimization methods are computationally intensive and prone to local minima. We address these limitations with a deterministic gradient-based optimization process. Using a differentiable error function, we efficiently perform gradient backpropagation to identify optimal parameters. To minimize the number of wigglers while maintaining accuracy, we adopt a recursive strategy: starting with a single wiggler and iteratively adding one at a time, using results from prior steps as seeds. This approach accelerates optimization and reduces computational demands. Building on this method, we design a feedback control strategy for real-time correlation generation with transverse wigglers, enabling precise, flexible beam manipulation and new possibilities in accelerator physics.
Paper: THPS098
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPS098
About: Received: 28 May 2025 — Revised: 04 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 05 Nov 2025
THPS109
Non-destructive measurements of non-relativistic ion beam bunch shapes at RAON
3189
Characterizing the longitudinal bunch profile is crucial for understanding beam dynamics and ensuring optimal accelerator performance. To address these needs, Capacitive Pick-Up type Bunch Shape Monitors (CPU-BSMs) were developed at the Institute for Rare Isotope Science (IRIS). These devices non-destructively measure the longitudinal bunch shapes of non-relativistic, nanosecond-scale ion beam bunches. Initial feasibility tests were conducted at a 30 MeV cyclotron to verify the performance of the CPU-BSMs. Subsequently, in 2024, the CPU-BSMs were employed during Nuclear Data Production System (NPDS) beam commissioning at the Rare Isotope Accelerator complex for ON-line experiments (RAON) to characterize both the longitudinal bunch shapes and the beam energy values. In this presentation, we will report the experimental results obtained using the CPU-BSMs during the NPDS beam commissioning at RAON.
Paper: THPS109
DOI: reference for this paper: 10.18429/JACoW-IPAC2025-THPS109
About: Received: 06 Jun 2025 — Revised: 14 Jun 2025 — Accepted: 14 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