plasma
MOCD1
Updated baseline design for HALHF: the hybrid, asymmetric, linear Higgs factory
53
Plasma accelerators promise significantly more compact, affordable and greener next-generation facilities, including linear colliders. While high-efficiency and -quality plasma acceleration of electron beams has been achieved, positron beams are much more challenging. The HALHF* (hybrid, asymmetric, linear Higgs factory) collider concept sidesteps the positron problem by accelerating them using RF cavities, while plasma acceleration to much higher energy is utilised for electrons. We report on an updated HALHF baseline design, which is more realistic, more upgradable to higher energies and includes additional capabilities such as positron polarization. Preliminary start-to-end simulations of the new baseline are also described.
Paper: MOCD1
DOI: reference for this paper: 10.18429/JACoW-IPAC25-MOCD1
About: Received: 28 May 2025 — Revised: 01 Jun 2025 — Accepted: 02 Jun 2025 — Issue date: 10 Jul 2025
MOPB025
Plasma based optics for electron beam fast micro-bunching
118
The utilization of plasma devices in beam transport is slowly being accepted as a worthy alternative thanks to its potential in maintaining or even reducing particle beams emittance but also for its compactness which supplements the recent advances in compact laser plasma acceleration systems. However, their use can go beyond the substitution of magnets. In this work, the utilization of a low density plasma device to micro-bunch electron beams through a "cascade focusing" caused by the beam generated wake inside the plasma. In addition, specialized particle in cell tools to study such phenomena over long distance (>cm) taking advantage of relativistic reference frames is swiftly presented. Such devices present a great potential for shortening future FEL facilities and increasing the efficiency of current.
Paper: MOPB025
DOI: reference for this paper: 10.18429/JACoW-IPAC25-MOPB025
About: Received: 29 May 2025 — Revised: 30 May 2025 — Accepted: 01 Jun 2025 — Issue date: 10 Jul 2025
MOPS027
Preliminary results from the CLEAR nonlinear plasma lens experiment
655
Plasma lensing provides compact focusing of electron beams, since they offer strong focusing fields (kT/m) in both planes simultaneously. This becomes particularly important for highly diverging beams with a large energy spread such as those typically originating from plasma accelerators. The lens presented here is a nonlinear active plasma lens, with a controlled focusing-strength variation purposely introduced in one transverse direction. This lens is a key element of a larger transport lattice, core of the ERC project SPARTA, which aims to provide a solution for achromatic transport between plasma-accelerator stages. We report on preliminary experimental results from the CLEAR facility at CERN, which aims to probe the magnetic field structure of the lens using an electron beam, in search of the desired nonlinearity, together with 2D plasma simulation results.
Paper: MOPS027
DOI: reference for this paper: 10.18429/JACoW-IPAC25-MOPS027
About: Received: 27 May 2025 — Revised: 04 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 10 Jul 2025
MOPS047
Development of new ion beams at the CERN ion injector complex for future physics programmes
718
In an effort driven by the requests from different physics experiments at CERN, the CERN ion injector complex is looking to expand its capabilities by providing lighter-than-lead ion beams. Argon and xenon were delivered for NA61/SHINE physics in 2015 and 2017, with xenon also reaching the LHC in 2017. Oxygen is foreseen to be collided in the LHC in 2025, with magnesium, boron and krypton beams also being prepared. Before new ion species can be considered operational for experiments, the feasibility of producing and accelerating these beams throughout the accelerator complex has to be assessed. This contribution presents an overview of the performance of the ion complex with recently tested magnesium ion beams, the latest results of the ongoing oxygen beam commissioning, and future plans concerning ion species that still need to be developed.
Paper: MOPS047
DOI: reference for this paper: 10.18429/JACoW-IPAC25-MOPS047
About: Received: 02 Apr 2025 — Revised: 03 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 10 Jul 2025
MOPS128
User research at Brookhaven Accelerator Facilities Division
814
Brookhaven's Accelerator Facilities Division provides users with access to cutting-edge research tools, including the Accelerator Test Facility (ATF) and the Ultrafast Electron Diffraction (UED) facility. The ATF features an RF photocathode electron LINAC, a femtosecond Ti:Sa laser, and a high-peak-power LWIR laser, all capable of synchronized or independent operation. These tools enable advancements in beam manipulation, accelerator and laser technologies, and the study of low-plasma-density regimes for precise electron seeding into plasma cavities. This supports the development of low-emittance beams for compact laser wakefield accelerators (LWFAs), with applications in science and industry. The UED facility, equipped with an RF electron gun and Ti:Sa laser, facilitates dynamic studies of material structures and other low-energy electron beam research. Starting in 2025, access to these facilities will be available through the BeamNetUS program for academia, industry, and national labs. These unique research opportunities will be presented.
Paper: MOPS128
DOI: reference for this paper: 10.18429/JACoW-IPAC25-MOPS128
About: Received: 30 May 2025 — Revised: 02 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 10 Jul 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-IPAC25-TUPB052
About: Received: 29 May 2025 — Revised: 04 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 10 Jul 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-IPAC25-TUPB082
About: Received: 26 May 2025 — Revised: 03 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 10 Jul 2025
TUPM085
An upgrade to the normal conducting miniature transport line for laser plasma accelerator-driven FELs
1349
In this contribution, we present advancements in upgrading the employed normal-conducting electron beam transport line at the JETI laser facility, University of Jena. To address spectral broadening caused by the large energy spread in Laser-plasma accelerators (LPAs), a transverse gradient undulator (TGU) with an energy acceptance of ΔE/E0 = ±10% has been developed. Although efficiently transporting the electron beam from the LPA to the TGU within this acceptance range required an optimized beam transport line too. Phase-space analysis for single particles across this energy range revealed that earlier transport line designs at KIT exhibited a nonlinear dependence of beam transverse position x on energy deviation, leads to beam dynamics complication. By incorporating combined dipole-quadrupole magnets, maintaining a transport line length of 2.9 m for 300 MeV beams, a linear relationship between transverse position x and energy deviations was achieved, with minimal variation in the phase x' (less than 2.4 × 10−4). This redesigned transport line meets the TGU's dispersion requirements, enabling more precise beam alignment and transport.
Paper: TUPM085
DOI: reference for this paper: 10.18429/JACoW-IPAC25-TUPM085
About: Received: 28 May 2025 — Revised: 05 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 10 Jul 2025
TUPM086
Simulation study of beam-driven plasma wakefield experiments on CLARA
1353
The Compact Linear Accelerator for Research and Applications (CLARA) is an electron test facility capable of delivering tunable 250 MeV electron beams with up to 250 pC charge to the Full Energy Beam Exploitation (FEBE) experimental area . In this study, we investigate the feasibility of conducting beam-driven plasma wakefield acceleration (PWFA) experiments using the CLARA beam and experimental area. We present simulations of various potential experiments, considering the baseline and R&D beam parameters expected to be delivered to the FEBE experimental chambers*. Our findings highlight the potential for CLARA to support advanced PWFA research, with detailed analysis of beam dynamics and experimental configurations.
Paper: TUPM086
DOI: reference for this paper: 10.18429/JACoW-IPAC25-TUPM086
About: Received: 28 May 2025 — Revised: 04 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 10 Jul 2025
TUPM094
Simulations of transverse dynamics in a laser-plasma accelerator
1376
Laser Wakefield Accelerators (LWFA) offer a promising solution for producing high-energy electron beams in compact setups. Beyond obtaining the required energy, the beam quality (emittance, energy spread, intensity) must also be optimized for LWFA to be considered an alternative to conventional accelerators. Achieving precise control of the transverse beam dynamics is one of the key challenges. This article thoroughly studies the physics governing the evolution of emittance and Twiss parameters within the plasma stage, on the density plateau, and in the up-ramp and down-ramp connections to conventional transport lines. Analytical and numerical analysis will be conducted using a toy model made of special quadrupoles, allowing numerical calculations to be sped up to a few seconds/minutes. Matching between plasma and transport lines will be extensively studied, clearly showing the dependence on initial conditions, and recommendations for the best realistic configurations will be provided*.
Paper: TUPM094
DOI: reference for this paper: 10.18429/JACoW-IPAC25-TUPM094
About: Received: 03 Jun 2025 — Revised: 03 Jun 2025 — Accepted: 03 Jun 2025 — Issue date: 10 Jul 2025
TUPM096
Development of an achromatic spectrometer for a laser-wakefield-accelerator experiment
1383
The large gradients of plasma-wakefield accelerators promise to shorten accelerators and reduce their financial and environmental costs. For such accelerators, a key challenge is the transport of beams with high divergence and energy spread. Achromatic optics is a potential solution that would allow staging of plasma accelerators without beam-quality degradation. For this, a nonlinear plasma lens\* is being developped within the SPARTA\*\* project. As a first application of this lens, we aim to implement an achromatic spectrometer for electron bunches produced by a laser-wakefield accelerator. We report on progress in designing such an experiment.
Paper: TUPM096
DOI: reference for this paper: 10.18429/JACoW-IPAC25-TUPM096
About: Received: 16 May 2025 — Revised: 03 Jun 2025 — Accepted: 03 Jun 2025 — Issue date: 10 Jul 2025
TUPM097
Study of electron density in capillary discharge plasma for laser plasma accelerator
1387
Laser-plasma accelerators have demonstrated the ability to accelerate high-energy electrons but require improved beam stability and repeatability for practical applications. Pre-formed plasma channels enhance the stability in Laser-Wakefield Accelerators by maintaining laser focus over longer distances, increasing energy transfer efficiency. The characteristics of such channels are highly dependent on capillary geometry, gas parameters, discharge setup, and repetition rate. This study investigates the electron density profiles in plasma from gas-filled capillary discharges. Using interferometry and Stark broadening, we measured profiles under varying conditions, achieving densities of (2-6)×10^18 cm^-3. In this presentation, we showcase the stability and uniformity of the plasma, highlighting its capability to preserve beam quality in high-energy, high-repetition-rate applications. This type of plasma source is a crucial technology for the plasma accelerator-based Free Electron Laser developed at ELI-ERIC as well as for the EuPRAXIA project. Also, we discuss the conceptual design of plasma diagnostics for providing 'real-time' information in high-repetition-rate applications.
Paper: TUPM097
DOI: reference for this paper: 10.18429/JACoW-IPAC25-TUPM097
About: Received: 27 May 2025 — Revised: 03 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 10 Jul 2025
TUPS005
Developing expectations for AWAKE with simulations
1419
The AWAKE experiment at CERN makes use of a self-modulated proton bunch to excite wakefields and accelerate a witness electron bunch. Run 2c of the experiment will demonstrate stabilization of the wakefield amplitude and control of the witness bunch emittance during injection and acceleration. In this work, we present an overview of the ongoing simulation efforts to support the project as it moves towards controlled acceleration and first particle-physics applications.
Paper: TUPS005
DOI: reference for this paper: 10.18429/JACoW-IPAC25-TUPS005
About: Received: 28 May 2025 — Revised: 30 May 2025 — Accepted: 30 May 2025 — Issue date: 10 Jul 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-IPAC25-TUPS006
About: Received: 28 May 2025 — Revised: 04 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 10 Jul 2025
TUPS009
Advancing plasma accelerator science: Insights from the EuPRAXIA Doctoral Network
1426
The EuPRAXIA Doctoral Network (EuPRAXIA-DN) trains the next generation of scientists in plasma-based accelerator technologies, addressing challenges in laser-plasma interactions, advanced beam diagnostics, and novel applications. This contribution highlights progress made in three critical areas: ) real‑time characterization of capillary discharge plasmas to stabilize laser‑wakefield accelera-tion, (ii) femtosecond‑precision X‑band low‑level RF (LLRF) control for the compact EuPRAX-IA@SPARC_LAB injector, and (iii) active‑plasma‑lens (APL)–based beam transport enabling extreme‑ultraviolet free‑electron‑laser (EUV‑FEL) operation within four me-ters of undulator. The innovative training elements with-in the network, such as the EuPRAXIA School on Plasma Accelerators held in Rome in April 2024 and upcoming EuPRAXIA Camps, are also discussed. It is shown how these foster knowledge exchange and skill development for the network's Fellows and the wider plasma accelera-tor community.
Paper: TUPS009
DOI: reference for this paper: 10.18429/JACoW-IPAC25-TUPS009
About: Received: 28 May 2025 — Revised: 31 May 2025 — Accepted: 05 Jun 2025 — Issue date: 10 Jul 2025
TUPS011
Transverse tolerances in the plasma-wakefield acceleration blow-out regime
1434
We report on recent progress in transverse instabilities and transverse tolerances for plasma-wakefield accelerators in the blow-out regime. In this regime, the transverse fields provide both strong focusing and strong deflection via transverse wakefields. The deflection effect of the wakefields on the main beam leads to limitations on the acceleration efficiency, if not mitigated. Based on comprehensive particle-in-cell simulations we summarize recent findings of the instability--efficiency relation for the blow-out regime. Ion motion and energy spread may mitigate the instability; with linac start-to-end simulations, using the recently developed ABEL framework, we demonstrate that the instability and emittance growth may be sufficiently mitigated for the colliding beams in the HALHF concept. Independent of wakefield effects, the strong focusing fields lead to very tight tolerances for the drive-beam jitter. We quantify these tolerances, using examples from HALHF start-to-end simulations. We show that the tolerances are greatly loosened by applying external magnetic fields to guide the drive-beam propagation in the plasma.
Paper: TUPS011
DOI: reference for this paper: 10.18429/JACoW-IPAC25-TUPS011
About: Received: 28 May 2025 — Revised: 04 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 10 Jul 2025
TUPS012
ABEL: The adaptable beginning-to-end linac simulation framework
1438
We introduce ABEL, the Adaptable Beginning-to-End Linac simulation framework developed for agile design studies of plasma-based accelerators and colliders. ABEL’s modular architecture allows users to simulate particle acceleration across various beamline components*. The framework supports specialised codes such as HiPACE++, Wake-T, ELEGANT, GUINEA-PIG and CLICopti, which facilitate precise modelling of complex machine components. Key features include simplified models for addressing transverse instabilities, radiation reactions, and ion motion, alongside comprehensive diagnostics and optimisation capabilities. Our simulation studies focus on the HALHF plasma linac, examining tolerances for drive beam jitter, including effects of self-correction mechanisms. Simulation results demonstrate ABEL's ability to model emittance growth under transverse instability and ion motion, highlighting the framework’s adaptability in balancing simulation fidelity with computational efficiency. The findings point towards ABEL’s potential for advancing compact accelerator designs and contribute to the broader goals of enhancing control and precision in plasma-based acceleration.
Paper: TUPS012
DOI: reference for this paper: 10.18429/JACoW-IPAC25-TUPS012
About: Received: 27 May 2025 — Revised: 03 Jun 2025 — Accepted: 03 Jun 2025 — Issue date: 10 Jul 2025
TUPS013
Ion-motion simulations of a plasma-wakefield experiment at FLASHForward
1442
In plasma-based acceleration, an ultra-relativistic particle bunch—or an intense laser beam—is used to expel electrons from its propagation path, forming a wake that is devoid of electrons. The ions, being significantly more massive, are often assumed to be stationary. However, both theory and simulations suggest that any sufficiently dense electron bunch can trigger ion motion, and its effect must be taken into account. We simulate beam-driven plasma wakefields to identify key features—such as longitudinally dependent emittance growth—that could be observed in an experiment using plasma and beam parameters from the FLASHForward facility at DESY.
Paper: TUPS013
DOI: reference for this paper: 10.18429/JACoW-IPAC25-TUPS013
About: Received: 28 May 2025 — Revised: 03 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 10 Jul 2025
TUPS054
Optimization of a multichannel solid state plasma for laser wakefield acceleration with realistic laser parameters using a Bayesian algorithm
1552
Nanostructures based on carbon nanotube arrays are emerging as promising media for achieving ultra-high acceleration gradients in laser wakefield acceleration (LWFA). In this study, we design and optimize plasmas with hexagonal lattice structures, where the lattice parameters directly define the nanostructure's properties. Using WarpX, a state-of-the-art particle-in-cell (PIC) simulation framework, we conduct fully three-dimensional simulations to model the interaction between these advanced plasmas and laser pulses. To refine the lattice parameters, we apply Bayesian optimization through the Python library BoTorch, identifying optimal configurations for generating effective wakefields. These results are intended to guide preliminary simulations for future experiments at leading laser facilities, such as ELI and VEGA3, advancing the exploration of LWFA with nanostructured plasmas.
Paper: TUPS054
DOI: reference for this paper: 10.18429/JACoW-IPAC25-TUPS054
About: Received: 16 May 2025 — Revised: 31 May 2025 — Accepted: 02 Jun 2025 — Issue date: 10 Jul 2025
TUPS110
Implementation of novel acceleration functionality in BDSIM
1601
Beam Delivery Simulation (BDSIM) is a Geant4 based accelerator tracking code which includes interactions of particles with material. BDSIM has become an important code in the accelerator community to simulate beam lines. Since laser and beam driven plasma wakefield acceleration (LWFA/PWFA) is a promising acceleration method we found it important to include related capability in BDSIM. This requires the addition of new beamline elements that are commonly used in plasma acceleration experiments. A gas volume where the LWFA/PWFA takes place and a beam mask to create a separate drive beam and a witness beam. In the former, the beam interacts with gas so ideal gas calculations are required to input the gas properties. Biasing can specifically be applied to the gas material in those elements. Simulating the interactions between the beam and a plasma is not done in BDSIM. An external software is used to compute the fields and the particles data. BDSIM can now read the output HDF5 files to reconstruct the fields inside the gas capillary or use the particle data as a bunch definition for the beginning of a beamline. Some results explaining how to make a LWFA/PWFA simulation are presented.
Paper: TUPS110
DOI: reference for this paper: 10.18429/JACoW-IPAC25-TUPS110
About: Received: 28 May 2025 — Revised: 04 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 10 Jul 2025
TUPS111
Optical and laser systems for the AWAKE run 2C experiment
1604
In the AWAKE Run 2c experiment, two electron beams are injected into two separate rubidium (Rb) vapour sources. The first electron beam initiates the self-modulation of a proton bunch in the first vapour source, while the second electron beam serves as a witness beam for plasma wakefield acceleration with low energy spread in the second vapour source. This setup requires the precise spatio-temporal delivery of four laser beams: two deep UV beams that generate the electron beams with a relative timing jitter well below 100 fs, and two near-IR beams that ionize efficiently the Rb vapour sources. The UV pulses are generated by an established Yb laser system, capable of producing 400 uJ, 0.2-10 ps pulses at 257 nm with high reliability (<0.1% RMS energy fluctuation), and enables emittance optimization via spatial beam shaping. The same system is used for both electron sources, utilizing a partial reflector to split the beam and account for differing photocathode yields. For the Rb ionizing pulses, which are directed into the vapour sources in a counter-propagating geometry, the pulses from the AWAKE Ti:Sapphire laser system are transported using a series of vacuum relay telescopes.
Paper: TUPS111
DOI: reference for this paper: 10.18429/JACoW-IPAC25-TUPS111
About: Received: 15 Apr 2025 — Revised: 30 May 2025 — Accepted: 01 Jun 2025 — Issue date: 10 Jul 2025
TUPS113
3D characterization of plasma density in capillary discharges for plasma-based accelerators
1608
Accurate characterization of plasma density profiles is vital for optimizing plasma-based accelerators, as density directly affects beam acceleration and quality. Plasma capillaries also serve as lenses and for beam guiding, highlighting their role in advanced accelerators. This study measures longitudinal and transverse density profiles of plasma capillaries, achieving 3D characterization using Stark broadening techniques. Two optical lines capture emitted plasma light. Parameters include gas flow rate, operating mode (pulsed/continuous), voltage, capillary type and geometry, gas type, and repetition rate, allowing evaluation of operational impacts on plasma density. Results show consistent density measurements across various positions, indicating the method's capability to capture spatial variations in plasma density. Understanding these profiles is crucial for developing and optimizing laser-driven and beam-driven plasma accelerators, as well as enhancing plasma lenses and beam guiding, enabling fine-tuning of parameters to maximize acceleration efficiency and control beam quality.
Paper: TUPS113
DOI: reference for this paper: 10.18429/JACoW-IPAC25-TUPS113
About: Received: 28 May 2025 — Revised: 02 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 10 Jul 2025
TUPS115
Optimization of the driver energy deposition in plasma wakefield acceleration simulations by varying transverse offset of sextupole magnets
1611
Plasma Wakefield Acceleration (PWFA) is a method of accelerating charged particles using a plasma. It has the potential to produce exceptionally large accelerating gradients on the order of 10’s of GeV/m. The FACET-II test facility accelerates pairs of 10 GeV electron bunches to study the PWFA process—a drive bunch to produce a wake in the plasma in a lithium-ion oven, and a witness bunch to be accelerated by PWFA. By using arrangements of sextupole magnets, it is possible to alter the chromaticity and other energy-dependent properties of the beams prior to their entry into the plasma. The purpose of this study was to determine how the transverse offsets of the sextupole magnets could be optimized to increase the amount of energy deposited into the plasma by the drive bunch as this energy deposition is critical to maximising the efficiency of PWFA. To achieve this, a simulation of the FACET-II beamline was performed with sextupole offsets as adjustable parameters in a Bayesian Optimization procedure. The results demonstrate the value of using beam simulations as guides to improve the PWFA process, thereby reducing the need to perform costly experiments at the FACET-II facility.
Paper: TUPS115
DOI: reference for this paper: 10.18429/JACoW-IPAC25-TUPS115
About: Received: 28 May 2025 — Revised: 02 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 10 Jul 2025
TUPS120
The SPARTA project: toward a demonstrator facility for multistage plasma acceleration
1615
Plasma acceleration is a rapidly maturing technology, but is not yet ready for large-scale applications such as linear colliders. The SPARTA project aims to develop a near-term, medium-scale plasma-accelerator facility to enable new experiments in strong-field quantum electrodynamics (SFQED)—an application that requires solving two of the most important remaining challenges in plasma acceleration: reaching high energy by using multiple accelerating stages; and achieving high beam stability. We report on progress toward the three main objectives: demonstrating a nonlinear plasma lens for achromatic beam transport between stages; developing self-stabilization and instability suppression mechanisms; and developing a conceptual design for a multistage SFQED facility.
Paper: TUPS120
DOI: reference for this paper: 10.18429/JACoW-IPAC25-TUPS120
About: Received: 20 May 2025 — Revised: 01 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 10 Jul 2025
TUPS134
Improvement of electron beam properties for Few-TW LWFA conducted in a sub-mm gas cell filled with a helium-nitrogen mixture
1627
Developing a laser wakefield acceleration (LWFA) scheme by focusing few-TW laser pulses into a thin, dense gas target paves the way for generating high-average-current electron beams driven by a modern high-repetition-rate laser. Our previous study demonstrated that using a sub-mm nitrogen (N₂) gas cell facilitates the routine generation of 10-MeV-scale electron beams from few-TW LWFA with ionization-induced injection*. However, excessive ionization-induced defocusing of the pump laser pulse tends to occur in an N₂ target, motivating the use of a helium (He) – nitrogen (N₂) mixture as the gas target to mitigate pump pulse defocusing in few-TW LWFA**. In this study, the effect of nitrogen doping ratio ranging from 0.5% to 5% was investigated using 40-fs, 1-TW pulses with a 0.4-mm-long gas cell. We found that a manifest peak repeatedly appears around 10 MeV in the energy spectra with the 99.5% He - 0.5% N₂ gas mixture - a result never observed with the pure N₂ cell. Using the He-N₂ mixture also leads to a noticeable increase in the charge of high-energy electrons (>5 MeV) and a reduction in the pointing fluctuation of the output beams compared to the pure N₂ target.
Paper: TUPS134
DOI: reference for this paper: 10.18429/JACoW-IPAC25-TUPS134
About: Received: 27 May 2025 — Revised: 04 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 10 Jul 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-IPAC25-WEPB065
About: Received: 27 May 2025 — Revised: 02 Jun 2025 — Accepted: 02 Jun 2025 — Issue date: 10 Jul 2025
WEPS039
Progress & developments of beam delivery simulation (BDSIM)
2325
BDSIM (Beam Delivery Simulation) is a Monte Carlo particle tracking tool for accelerator beamline modelling. It integrates particle transport with detailed geometry and physics using Geant4 for precise modelling of particle-matter interactions in 3D models of particle accelerators. Primarily for energy deposition studies and beam loss simulations, BDSIM allows a high degree of control and customisation, and is ideal for understanding and enhancing the performance of beamline designs. BDSIM has numerous modelling applications, including high-energy physics facilities, particle detection experiments, synchrotron light sources, medical accelerators, and novel acceleration experiments. Here, we present recent developments of BDSIM. This includes improved custom inverse-Compton scattering processes for laserwire and polarimeter simulations and extending the process to model polarization & electron spin; improved acceleration including transverse focussing in RF elements with implementation of 3D transverse magnetic and electric modes; custom elements for modelling muon cooling channels; and updates to interfacing with Xsuite via improved code couplings and BDSIM distribution methods.
Paper: WEPS039
DOI: reference for this paper: 10.18429/JACoW-IPAC25-WEPS039
About: Received: 28 May 2025 — Revised: 01 Jun 2025 — Accepted: 02 Jun 2025 — Issue date: 10 Jul 2025
WEPS145
Plasma processing of ESS elliptical cavities
2458
Plasma treatment has proven effective in recovering and reducing field emission in the affected superconducting radiofrequency (SRF) cavities. A joint effort is underway between CEA, ESS and INFN to apply this technique to the treatment of elliptical cavities in the ESS linac. This paper presents the work done so far, which aims at both the development of the plasma process for cavities in the cryomodule and the treatment of cavities in the vertical test configuration. The peculiarity of ESS cavities compared with typical cavities at 1.3 GHz is the absence of couplers for higher orders.
Paper: WEPS145
DOI: reference for this paper: 10.18429/JACoW-IPAC25-WEPS145
About: Received: 28 May 2025 — Revised: 03 Jun 2025 — Accepted: 03 Jun 2025 — Issue date: 10 Jul 2025
THAD2
A method for measuring energy gain with variable plasma length at AWAKE
2469
The Advanced Wakefield (AWAKE) experiment is a proof-of-principle accelerator facility at CERN (Geneva, Switzerland). Proton bunches from the CERN Super Proton Synchrotron are used to drive wakefields in 10 metres of laser-ionised rubidium plasma, over which externally injected 19 MeV electrons are accelerated. Run 1 of AWAKE successfully demonstrated the self-modulation of the long proton bunch, and the acceleration of electrons to 2 GeV. Upgrades to the rubidium vapour source during Run 2 have enabled the use of a plasma density step, and variation of the plasma length through the insertion of foils along the source to dump the laser pulse. When placed suitably within the development of self-modulation, the density step is expected to preserve the wakefield amplitude, and therefore accelerating gradient, over longer distances than with uniform plasma. This work presents the first measurements of electron acceleration with a density step, studied as a function of the plasma length.
Paper: THAD2
DOI: reference for this paper: 10.18429/JACoW-IPAC25-THAD2
About: Received: 08 Apr 2025 — Revised: 04 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 10 Jul 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-IPAC25-THPB008
About: Received: 28 May 2025 — Revised: 04 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 10 Jul 2025
THPS042
Evaluation of an X-band LLRF prototype for the EuPRAXIA@SPARC_LAB LINAC
3054
EuPRAXIA, the "European Plasma Research Accelerator with eXcellence In Applications," represents the next generation of free-electron lasers (FEL). It aims to develop a compact, cost-efficient particle accelerator using innovative wake-field accelerator technology. High-energy physics often demands higher acceleration voltages, and X-band technology offers high gradients in compact structures. The EuPRAXIA@SPARC_LAB LINAC injector, featuring an S-band RF gun, four S-band structures, and sixteen X-band structures, achieves a maximum beam energy of 1 GeV. For femtosecond-level synchronization and stability, Low-Level Radio Frequency (LLRF) systems are essential. However, commercial X-band LLRF solutions are unavailable. This project, in context of the EuPRAXIA - Doctoral Network, develops an X-band LLRF prototype tailored to meet the EuPRAXIA@SPARC_LAB LINAC's stringent requirements. After validation on a testbench, the prototype will enable industrial production and commercialization. This paper presents the Front-End, Back-End analysis, and further evaluation of the prototype.
Paper: THPS042
DOI: reference for this paper: 10.18429/JACoW-IPAC25-THPS042
About: Received: 27 May 2025 — Revised: 02 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 10 Jul 2025
THPS043
A new EPICS based frequency synthesizer and power control system for the H¯ RF Ion Source at ISIS
3058
A Low-Level RF and Power Control system based on EPICS has been developed for the new H¯ RF Ion Source on the Pre-Injector Test Stand at ISIS Spallation Neutron and Muon source, UKRI-STFC Rutherford Appleton Laboratory. The Ion Source LLRF system provides a 2 MHz signal to a Solid-State 100 kW RF Amplifier that drives the Ion Source Plasma, the changing Plasma load requires fast Frequency agility and closed loop Power Control. This paper will detail the design and performance of the LLRF system.
Paper: THPS043
DOI: reference for this paper: 10.18429/JACoW-IPAC25-THPS043
About: Received: 28 May 2025 — Revised: 04 Jun 2025 — Accepted: 05 Jun 2025 — Issue date: 10 Jul 2025
FRZD2
BeamPIE – a suborbital test of an accelerator for space applications
3261
Summary: An experiment to fly an accelerator in space recently concluded successfully. Discuss the objectives, differences from terrestrial accelerators, and results from the flight. Accelerators have the potential to play a major role in space-based activities. These can range from investigation of the Earth’s magnetic field, to helping mitigate the effects of increased solar activity (e.g. by helping drain the Earth’s radiation belts of charged particles), to deep-space missions. There are many challenges associated with operating accelerators in a space-based environment, however, ranging from high-voltage systems, to thermal management, to spacecraft charging. The Beam-Plasma Interaction Experiment – BeamPIE – was a small electron accelerator launched on a sounding rocket in 2023, to both explore the interaction of an electron beam with the near-earth plasma environment, and to test several new approaches to accelerator design in a space environment. This talk presents an overview of the BeamPIE accelerator design, mission objectives, and results from its flight.
Paper: FRZD2
DOI: reference for this paper: 10.18429/JACoW-IPAC25-FRZD2
About: Received: 24 May 2025 — Revised: 04 Jun 2025 — Accepted: 04 Jun 2025 — Issue date: 10 Jul 2025