acceleration
MOCC01
Current Activities of the Beam Diagnostics in the J-PARC Linac
18
J-PARC Linac accelerates the high-intensity beam of 50 mA using an RF system of 324 MHz and 972 MHz. In order to accelerate and transport the high-intensity beam to facilities stably, the current value, centroid, and distribution of the beam must be measured to realize optimum operating conditions. This paper reports on the transformations and improvements of the linac beam diagnostics since 2015. As an example, carbon nanotubes (CNTs) were employed in the WSM at the upstream of the linac. There has never been an unintentional WSM failure after the CNT replacement. Other reports on the status of BSM operations will also be presented. The diagnosis of beam anomalies experienced during beam tuning will also be reported.
Paper: MOCC01
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-MOCC01
About: Received: 01 Sep 2025 — Revised: 05 Sep 2025 — Accepted: 09 Sep 2025 — Issue date: 20 Jan 2026
MOCC02
Beam diagnostics for IFMIF-DONES: addressing the challenges of high-power irradiation facilities
24
The IFMIF-DONES facility, currently under construction in Granada (Spain), is dedicated to testing materials under neutron irradiation, as part of advanced materials research for next-generation fusion reactors. The superconducting linear accelerator of the facility is intended to deliver a continuous-wave deuteron beam with an energy of 40 MeV and an unprecedented current of 125 mA. The production of neutrons is then achieved by driving the 5 MW beam into a liquid lithium target. Beam diagnostics play a critical role in the IFMIF-DONES accelerator due to several unique challenges. These include the extremely high beam power, the harsh environment due to neutron and gamma radiation and the required operational availability of the accelerator. Moreover, the accelerator may operate in pulsed and continuous wave for commissioning and standard operation, respectively. This work presents an overview of the main beam diagnostics techniques and strategies needed to address these challenges, as well as the construction plan and the prototyping works. ACKNOWLEDGEMENT This work has been carried out within the framework of the EUROfusion Consortium.
Paper: MOCC02
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-MOCC02
About: Received: 03 Sep 2025 — Revised: 09 Sep 2025 — Accepted: 09 Sep 2025 — Issue date: 20 Jan 2026
MOPCO01
End to end simulations of a novel optical fibre monitoring system for energy recovery LINACs
46
Energy recovery LINACs (ERLs) are a type of novel accelerator, which recycle energy from old beams to new beams to increase machine energy efficiency. However, this can heighten beam instabilities, which limits the maximum beam current and increases beam losses. An optical fibre beam loss monitor (OBLM) can provide rapid and reliable beam loss monitoring, which is important for mitigating these instabilities. It obtains the beam loss location via time-of-flight analysis of Cherenkov radiation (CR) produced in optical fibres by relativistic particle showers from beam loss events. Operational demonstration of the OBLM system has previously been shown at several non-ERL facilities, but the multi-energy, fast-repeating beams of ERLs present a unique challenge. Successful interpretation of ERL beam loss signals involves distinguishing losses from beams of different energies, which can be investigated through end-to-end Monte Carlo simulations of the radiation environment and its interaction with the OBLM system. This contribution presents Geant4 simulations of the OBLM response to sample sources of beam loss for beam energies of 7-500 MeV and bunch populations of 1-10M electrons.
Paper: MOPCO01
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-MOPCO01
About: Received: 26 Aug 2025 — Revised: 04 Sep 2025 — Accepted: 08 Sep 2025 — Issue date: 20 Jan 2026
MOPCO06
High-resolution diagnostics of the TOP-IMPLART 71 MeV proton beam using photoluminescent color centers in LiF crystals
66
Optically active point defects, known as color centers (CCs), are created in the crystal lattice of lithium fluoride (LiF) by irradiation with various types of ionizing radiation. Some of these CCs emit light in the red and green regions of the visible spectrum when optically excited with blue light. When a proton beam irradiates a LiF crystal, a volume distribution of CCs is formed, with defect concentration point-by-point proportional to the absorbed dose for values up to approximately 10^5 Gy. By illuminating the irradiated crystal with blue light in a fluorescence microscope, a luminescent image produced by the CCs can be observed and recorded. A high-resolution diagnostics both for spot imaging and energy in a proton accelerator has been developed based on this technique. Regarding energy, a luminescent replica of the Bragg curve in LiF is extracted and analyzed using a theoretical model of Bragg curve applied to dose deposition, taking into account the crystal dimensions. We report an application of this method to the 71 MeV TOP-IMPLART linac at ENEA Frascati, where it was used to evaluate the beam energy spectrum at both the crystal position and the accelerator exit.
Paper: MOPCO06
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-MOPCO06
About: Received: 31 Jul 2025 — Revised: 04 Sep 2025 — Accepted: 05 Sep 2025 — Issue date: 20 Jan 2026
MOPCO08
A 3GHz Wall Current Transformer for Very High Bandwidth Beam Current Measurements
74
Non-destructive beam current measurements are a crucial aspect of beam instrumentation in any particle accelerator. Often, these measurements must be capable of distinguishing individual beam pulses. In an increasing number of accelerators, pulse repetition rates reach the GHz range. Consequently, beam current measurement bandwidth must exceed a few GHz. To meet this requirement, a wall current transformer was developed with a bandwidth exceeding 3 GHz. It was tested using a vector network analyzer and with an electron beam at CERN's CLEAR facility. Both measurements showed excellent agreement. We introduce the wall current transformer principle and discuss the measurement results. Additionally, we highlight some challenges that must be addressed when measuring high-frequency signals.
Paper: MOPCO08
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-MOPCO08
About: Received: 22 Aug 2025 — Revised: 04 Sep 2025 — Accepted: 09 Sep 2025 — Issue date: 20 Jan 2026
MOPCO10
The impact of positional inaccuracy on 3D X-ray image quality
82
X-ray imaging of both material and biological samples is a key application of synchrotrons and laser wakefield accelerators. However, it is possible that undiagnosed beam location offsets can impact the quality of the image created. This is particularly the case in 3D imaging, for which the 3D reconstructions require precise knowledge of the location at which each x-ray projection was taken. This study uses a low-energy x-ray imaging device designed to perform mobile digital tomosynthesis (DT), a modality of 3D x-ray imaging, for veterinary scanning to investigate the impact of this. An intentional offset is randomly applied of size 0.5 mm and 1 mm from the expected x-ray source position, and the quality of the reconstructed image is assessed for both the case where this offset is accounted for, and where it is not. From this, it is concluded that x-ray beams used for 3D imaging applications can have up to a 1 mm error without seeing large degradation in reconstructed image quality.ht be in other modern x-ray contexts, such as within XFEL technology.
Paper: MOPCO10
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-MOPCO10
About: Received: 06 Sep 2025 — Revised: 07 Sep 2025 — Accepted: 07 Sep 2025 — Issue date: 20 Jan 2026
MOPCO14
Commissioning of the CLARA facility: status update and diagnostics performance
97
The Compact Linear Accelerator for Research and Applications (CLARA) is STFC Daresbury Laboratory’s flagship accelerator facility. We present the latest data from the commissioning of the CLARA facility at Daresbury Laboratory. This will include initial beam measurements and diagnostic performance for the 250 MeV high brightness, highly compressed electron bunches. An overview of the diagnostic requirements and anticipated challenges for these high impact user experiments will be provided. The future direction of diagnostics at CLARA, including potential system upgrades and plans for virtual diagnostics, is also discussed.
Paper: MOPCO14
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-MOPCO14
About: Received: 03 Sep 2025 — Revised: 05 Sep 2025 — Accepted: 08 Sep 2025 — Issue date: 20 Jan 2026
MOPCO23
Commissioning of the 71 MeV beam delivery line of the TOP-IMPLART accelerator
120
TOP-IMPLART is a pulsed RF proton linear accelerator in operation at the ENEA Frascati Research Center originally built as a technological demonstrator for a full-linear solution to protontherapy, it is currently evolving towards a facility available for research and industrial users in different fields, ranging from biomedical to aerospace applications. It consists of a commercial AccSys PL7 model 425 MHz injector followed by eight SCDTL accelerating modules operating at 3 GHz. Proton beams in the range 1-6 MeV are available from a vertical delivery line placed at the exit of the injector, and at 63 MeV or 71 MeV (intermediate and lower energies are achieved by degraders) from a horizontal delivery line at the exit of the accelerator, where a pulse current variable up to 20 µA is provided in pulses 2.5 µs long at a typical repetition rate of 25 Hz. Our contribution presents the first experimental results from the commissioning of the high-energy line. It is a multi-purpose in-house designed line featuring a magnetic scanning system and a set of instrumentation, diagnostics, and target positioning frames placed on motorized platforms allowing for customizable irradiation setups.
Paper: MOPCO23
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-MOPCO23
About: Received: 02 Sep 2025 — Revised: 05 Sep 2025 — Accepted: 09 Sep 2025 — Issue date: 20 Jan 2026
MOPCO26
Design and Simulation of Miniaturized Permanent Magnet Arrays for Compact Diagnostic Applications
128
This paper presents the design and simulation of miniaturized permanent magnet configurations for Nuclear Magnetic Resonance (NMR) applications where compactness and field quality are critical. Traditional NMR systems require large and costly equipment to achieve high magnetic field uniformity, which limits portability and broader diagnostic use. We investigate compact magnet geometries, including H-type and Halbach arrays, evaluating their field strength and homogeneity. Special attention is given to the trade-off between device miniaturization and achievable field uniformity, a key factor in measurement sensitivity. Through computational modelling, we establish a framework for quantifying and optimizing magnetic field homogeneity, providing design strategies relevant for portable diagnostic instrumentation and potential applications where in-situ, non-invasive measurements are required.
Paper: MOPCO26
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-MOPCO26
About: Received: 07 Sep 2025 — Revised: 08 Sep 2025 — Accepted: 10 Sep 2025 — Issue date: 20 Jan 2026
MOPCO32
Development of a fast extraction method for short high intensity pulses at ELSA
142
Studies concerning the FLASH effect for radiation therapy are currently performed at ELSA. The booster synchrotron is used in a preliminary mode of operation to deliver electron beam pulses of 1.2 GeV energy with fixed length of 250 ns to irradiate cell samples. To enable different spill durations ranging from nanoseconds up to several ms in an energy range of 0.8 to 3.2 GeV a fast extraction from the stretcher ring is developed. Therefore a repurposing of the existing injection kickers for extraction is under study to achieve single turn extraction, up to extraction within a few turns. While the effect on the beam dynamics is observed with a streak camera, the measurement of the extracted beam is performed via current and chromox monitors. For longer spill durations, reaching up to ms, the feasibility of multiple concepts for a quicker resonant extraction at ELSA is investigated.
Paper: MOPCO32
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-MOPCO32
About: Received: 03 Sep 2025 — Revised: 07 Sep 2025 — Accepted: 08 Sep 2025 — Issue date: 20 Jan 2026
MOPMO07
First Attila4MC simulations for the high-power proton accelerator of the European Spallation Source
183
Radiation transport simulations allow the design and operation of entire facilities such as the European Spallation Source (ESS) in Lund, Sweden. This paper summarizes three of the first applications of Attila4MC simulations to the high-power proton accelerator of ESS and its beam instrumentation. Entire linac sections and beam-interceptive instrumentation were modelled by implementing existing CAD models, relying on unstructured tetrahedral meshes and zeroing out the time spent in manually crafting MCNP6 models. As a result, it was possible to accurately quantify the beam power density within beam-interceptive devices and in turn their operational limits. Activation and 3D dose maps were computed and swiftly visualized in 3D, on top of the actual linac model. This work paves the way for e.g. advanced instrumentation design, linac operation, safe maintenance, categorization of radiation waste and future dismantling.
Paper: MOPMO07
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-MOPMO07
About: Received: 26 Aug 2025 — Revised: 04 Sep 2025 — Accepted: 06 Sep 2025 — Issue date: 20 Jan 2026
MOPMO13
Intelligent Retrieval Systems for Accelerator Physics: Matching Retrieval Approaches to Use Cases
204
Accelerator facilities generate diverse documentation, from technical reports to structured wikis and semi-structured logbooks, which complicates efficient knowledge access. While Retrieval-Augmented Generation (RAG) offers a path toward intelligent operator assistants, no single method is universally optimal. We present three use cases from PSI: for technical documentation, naive dense retrieval with summarization provides fast and interpretable access; for the AcceleratorWiki, a graph-augmented approach improves reasoning over hierarchies and cross-references; and for ELOG, an agentic pipeline with specialized agents supports multimodal interpretation, temporal reasoning, and iterative refinement. Together, these case studies illustrate how matching retrieval paradigms to data types enables reliable, context-aware assistance in accelerator operations.
Paper: MOPMO13
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-MOPMO13
About: Received: 08 Sep 2025 — Revised: 09 Sep 2025 — Accepted: 10 Sep 2025 — Issue date: 20 Jan 2026
MOPMO15
Beam Instrumentation for the new linear accelerator at the Canadian Light Source
212
The Canadian Light Source (CLS) linear accelerator (linac) serves as the injector for the 2.9 GeV synchrotron. The original linac, which was installed in the 1960's, was replaced in 2024. The new 3000.24 MHz linac was designed and built by RI Research Instruments GmbH. The linac makes use of a 90 kV thermionic source, three 5m long accelerating S-band structures and a SLED pulse compressor system to accelerate electrons to 250 MeV. The initial beam instrumentation included a faraday cup, yag screens, beam position monitors and fast current transformers. During the course of commissioning directional couplers and microphones were added to provide insight into the location of RF breakdowns. This paper will provide an overview of the new linear accelerator and our experience commissioning the new equipment.
Paper: MOPMO15
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-MOPMO15
About: Received: 03 Sep 2025 — Revised: 08 Sep 2025 — Accepted: 11 Sep 2025 — Issue date: 20 Jan 2026
MOPMO34
Performance Validation of High-Gradient X-Band Structures at the University of Melbourne’s X-LAB
260
The X-band Laboratory for Accelerators and Beams (X-LAB) at the University of Melbourne enables high-power testing of X-band accelerator technologies, including components for CERN’s Compact Linear Collider (CLIC). At its core is Mel-BOX, a high-gradient test stand rebuilt from CERN’s XBOX3. Two TD24 structures, previously conditioned at CERN, have been successfully re-tested, along with RF windows, SLED-I pulse compressors, and 3D-printed loads. Beam instrumentation at X-LAB includes Faraday cups with high-resolution digitizers to measure dark current and breakdown emissions. Fast time-domain measurements along the waveguide using GHz-bandwidth oscilloscopes allow localization of breakdown events. Optical fibers detect Cherenkov light near the structures, providing complementary pulse-resolved signals. These are cross-referenced with Faraday cup data to study early-stage field emission. X-LAB integrates RF testing and diagnostics to support the development of compact, high-gradient accelerator systems.
Paper: MOPMO34
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-MOPMO34
About: Received: 03 Sep 2025 — Revised: 08 Sep 2025 — Accepted: 10 Sep 2025 — Issue date: 20 Jan 2026
MOPMO35
Measurements of Dark Current and Breakdown Processes using Faraday Cups and Fast Digitisers at the XBand Laboratory for Accelerators and Beams (XLAB)
264
Two CLIC TD24 accelerating structures, manufactured by CERN, are undergoing high-power testing on the 12 GHz RF test stand, MelBOX, at the x-Band Laboratory for Accelerators and Beams (XLAB). Installed in late 2024, these are the first devices tested at the facility. The goal is to condition the structures for stable operation at gradients of 100 MV/m. The maximum gradient is limited by electrical breakdown—vacuum arc formation under high electric fields—which interrupts RF transmission and can damage the structure. To study breakdown dynamics and validate models of their initiation, detailed, time-resolved charge measurements are needed. Faraday cups upstream and downstream, combined with high-performance 5 GS/s, 12-bit, 3 GHz FEB digitisers, enable precise characterisation of both dark and breakdown current emissions. Fast digitiser readout allows continuous acquisition at the 400 Hz repetition rate, capturing breakdown events and several hundred preceding pulses. This dataset supports in-depth analysis of precursors. We present initial results from structure conditioning, including breakdown statistics, dark current trends, and preliminary analysis of breakdown behaviour.
Paper: MOPMO35
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-MOPMO35
About: Received: 03 Sep 2025 — Revised: 10 Sep 2025 — Accepted: 10 Sep 2025 — Issue date: 20 Jan 2026
MOPMO40
Development of an imaging protocol for laser driven X-ray sources
282
The Extreme Photonics Applications Centre (EPAC) being built at the Central Laser Facility in the UK will utilise a 10Hz Laser Wakefield Accelerator (LWFA) to produce a tuneable x-ray source, with energies ranging from 3keV up to 10’s of MeV while maintaining a micron-scale source size and ultra-short pulse duration. Combination of such characteristics opens an opportunity for cutting-edge high-resolution industrial imaging of dense materials: battery packs, historical artifacts and dynamic processes: crack propagation, motor engines running. The primary challenge in imaging with LWFA X-ray sources stems from shot-to-shot instabilities of flux, energies and pointing. We will present an imaging protocol developed using a combination of particle-in-cell, ray tracing and Monte Carlo simulations to simulate instabilities of EPAC and correct for them in x-ray radiographic and tomographic imaging.
Paper: MOPMO40
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-MOPMO40
About: Received: 02 Sep 2025 — Revised: 08 Sep 2025 — Accepted: 11 Sep 2025 — Issue date: 20 Jan 2026
MOPMO45
Fermilab PIP-II machine protection system digitized data noise elimination scheme and its FPGA implementation
294
In Fermilab's PIP-II machine protection system, beam loss signals from various detectors are digitized at 125 MS/s. Noise from both high-frequency sources and low-frequency 60 Hz AC power equipment can contaminate the data. To suppress noise across these ranges—especially 60 Hz and its harmonics, which overlap with beam loss signal frequencies—advanced digital processing beyond standard filtering is required. Several real-time functional blocks were simulated and tested on an FPGA: (1) a dual time-constant discharging integrator filter, (2) a de-ripple baseline extraction and storage block, and (3) a fast-recovery discharging integrator. The nonlinear IIR integrator filter removes high-frequency noise and feeds into the baseline extractor. Upon detecting abrupt beam loss, it switches to a longer time constant to prevent baseline distortion. The de-ripple block calculates a valid baseline by averaging over multiple 60 Hz periods, storing results in a 4096-word FPGA RAM. This baseline is subtracted from raw data before integration by the fast-recovery block, which resets quickly after use. All blocks achieved expected performance and were successfully implemented on a low-cost FPGA.
Paper: MOPMO45
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-MOPMO45
About: Received: 30 Aug 2025 — Revised: 09 Sep 2025 — Accepted: 10 Sep 2025 — Issue date: 20 Jan 2026
TUAI02
Towards continual machine learning for particle accelerators
302
This talk covers our work on errant beam prognostics at the Spallation Neutron Source (SNS), focusing on the end-to-end process from data collection to the development and deployment of predictive models in specific. A short overview of AIML work done for accelerators and current trends will be presented. We will walk through key steps involved in creating robust Machine Learning (ML) models, including model training, validation, and deployment in an operational setting. In addition to presenting our technical approach, we will share valuable lessons learned, emphasizing the importance of infrastructure to support the continuous adaptation of models to evolving data and system behaviors. This talk will provide insights into the challenges and solutions involved in applying ML to real-world operational environments, with a particular focus on managing data drift and changes in accelerator setup while ensuring model resilience over time.
Paper: TUAI02
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-TUAI02
About: Received: 04 Sep 2025 — Revised: 09 Sep 2025 — Accepted: 10 Sep 2025 — Issue date: 20 Jan 2026
TUBC02
Beam diagnostics, data acquisition system, and applications of machine learning at the KEK e-/e+ Linac
314
The KEK e⁺/e⁻ Linac supplies electron beams to SuperKEKB HER, PF, and PF-AR, and positron beams to SuperKEKB LER. We utilize machine learning for both online beam tuning and offline data analysis. Machine learning based on Bayesian optimization has been employed to improve and maintain beam quality, contributing to the enhancement and stabilization of beam injection efficiency into SuperKEKB HER and LER. In this report, we present monitors and beam tuning methods that incorporate machine learning. Identifying parameters that affect beam quality and stability is important, but finding them among the vast number of parameters is not easy. In machine learning-based beam tuning, selecting the appropriate parameters for tuning is crucial, and another important issue is identifying factors that lead to beam instability. To address this, we have applied explainable AI techniques to analyze archived data and attempted to extract parameters that have a significant impact on the beam. This report also covers our data archiving system and analysis efforts using explainable AI.
Paper: TUBC02
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-TUBC02
About: Received: 03 Sep 2025 — Revised: 05 Sep 2025 — Accepted: 09 Sep 2025 — Issue date: 20 Jan 2026
TUPCO08
Status of longitudinal instability suppression at NanoTerasu
362
NanoTerasu is a 3 GeV light source newly constructed in Sendai, Japan. The circumference is 349 m and the natural emittance is 1.1 nm rad, which is realized by a double-double-bend achromat lattice. The commissioning of the storage ring started in June 2023. The longitudinal instability was observed when the stored beam current reached 150 mA in August 2023. The temperature of RF cavity was adjusted to suppress the instability. The user operation was started on schedule in April 2024 with a stored beam current of 160 mA. The stored beam current was reached 200 mA without the beam instability in July 2024. The stored beam current at user operation period was limited to 200 mA by the longitudinal instability. We try to suppress the longitudinal beam instability using several methods. We developed the pillbox type RF kicker cavity to suppress the instability. In addition, we tried to suppress the longitudinal instability using the transverse feedback kicker. I will report the status of longitudinal instability suppression at NanoTerasu.
Paper: TUPCO08
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-TUPCO08
About: Received: 27 Aug 2025 — Revised: 08 Sep 2025 — Accepted: 10 Sep 2025 — Issue date: 20 Jan 2026
TUPCO12
Measurement of transverse profile in electron linacs: recent advances in SwissFEL
377
The measurement of transverse profiles of the electron beam is key to measuring and optimizing the emittance of a linear accelerator. Also, transverse profile monitors are used in conjunction with an RF deflecting structure to measure bunch length and slice emittance. An RF deflector and a profile monitor behind the undulator can furthermore be used to reconstruct the FEL pulse profile. I will give an overview on recent advances in beam profile measurements at SwissFEL, including scintillating screens as well as wire scanners. The goal of these advances is the improvement of the resolution in both screens and wire scanners, both by improving the optics, and by improved data processing. Furthermore, we are exploring the possibility to do non-invasive wire scans with micrometer-size wires.
Paper: TUPCO12
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-TUPCO12
About: Received: 08 Sep 2025 — Revised: 10 Sep 2025 — Accepted: 10 Sep 2025 — Issue date: 20 Jan 2026
TUPCO14
Status of oscillating arm wire monitor development
383
We present the development of a high-speed oscillating-arm wire monitor. Similar devices are in use at PSI’s HIPA facility since the 1970s, however they are significantly slower. The new design maintains the compact longitudinal footprint of the original instrument; a property rarely found among fast wire monitors. First performance tests demonstrated wire velocities of 4 m/s using a stepper motor and 8 m/s with a servo motor. This advancement will allow to use wire scanners to measure the beam profile in the most challenging of the HIPA beamlines, with beam current exceeding 10 mA.
Paper: TUPCO14
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-TUPCO14
About: Received: 06 Sep 2025 — Revised: 09 Sep 2025 — Accepted: 10 Sep 2025 — Issue date: 20 Jan 2026
TUPCO16
IRRADIATION TESTS OF A DIGITAL RADIATION-TOLERANT CAMERA FOR CERN’S PARTICLE ACCELERATOR INSTRUMENTATION
391
Beam imaging systems are integral parts of beam instru- mentation at CERN, measuring the shape, size, and position of particle beams in accelerators. Following the worldwide phasing out of analog cameras and vidicon tubes (which the system was initially based on and still partially uses), part of the ongoing consolidation program involves developing a new camera system based on digital technology for use in CERN’s medium radiation environments up to few 100 Gy total dose. For this purpose, the CERN Beam Instrumentation group initiated the development of a digital camera system in col- laboration with MCSE*, a Swiss company specializing in space instrumentation. The new camera’s performance un- der radiation was evaluated at CERN’s CHARM test facility, with promising results in terms of radiation immunity while maintaining sufficient sensitivity and resolution—which will be the focus of this contribution. Following this prototyping phase, an industrial version is now in development and is expected to undergo testing in 2025.
Paper: TUPCO16
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-TUPCO16
About: Received: 03 Sep 2025 — Revised: 08 Sep 2025 — Accepted: 11 Sep 2025 — Issue date: 20 Jan 2026
TUPCO21
Low energy experimental bench (LEEx-B) and emittance-meter developments at IPHC
406
A low energy experimental bench called LEEx-B is being developed at IPHC-CNRS of Strasbourg, France. The bench is composed of a CS+ ion gun mounted on a HV platform and beams up to 25 keV are provided. The main objective of this bench is to support the advancement of beam diagnostics, including the ongoing development of the Allison-type emittance-meter. This paper presents the progress of the construction of the LEEx-B and of the beam diagnostics.
Paper: TUPCO21
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-TUPCO21
About: Received: 01 Sep 2025 — Revised: 05 Sep 2025 — Accepted: 07 Sep 2025 — Issue date: 20 Jan 2026
TUPCO22
Cherenkov radiation spectral and resolution properties studies at SINBAD ARES
409
Optical Cherenkov Radiation (ChR) is a well-known type of radiation, which is utilized in different fields of physics such as charged particle detection or generation of intense THz radiation. It is also widely used in beam diagnostics, for instance, in beam loss monitors or for bunch length measurements. In addition, it is of potential interest for transverse beam profile diagnostics as an alternative for standard techniques as scintillating screens and optical transition radiation. In this work, spectral and resolution properties of optical ChR were studied at the SINBAD ARES accelerator with an electron beam energy of 150 MeV. Several fused silica crystals of different thicknesses were used as radiators. They could be rotated relative to the beam, which allowed to investigate the angular dependency of the ChR spectrum which is quasi-monochromatic. The monochromatization effect arises from the frequency-dependent nature of the fused silica permittivity. In addition, the beam size dependency on the target angle was investigated in view of differences for various crystal thicknesses.
Paper: TUPCO22
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-TUPCO22
About: Received: 03 Sep 2025 — Revised: 06 Sep 2025 — Accepted: 07 Sep 2025 — Issue date: 20 Jan 2026
TUPCO24
Design and Programming of a Multifunctional Device for Accelerator Beam Profile Measurement and Beam Stop
413
During the pre-research phase of China Spallation Neutron Source (CSNS) upgrade project (CSNS-II), in order to conduct beam commissioning of the Radio Frequency Quadrupole (RFQ) under high-intensity beam conditions, The structure of the last-stage wire scanner of the Medium Energy Beam Transport (MEBT) was innovatively modified. This modification not only added a Beam Stop but also significantly enhanced the efficiency of wire scanner. This paper presents the architecture and operational programming of a novel multifunctional device designed for accelerator beam diagnostics and beam termination: beam profile measurement via advanced sensing mechanisms and Beam Stop using a braided carbon fiber plate as the primary beam stop.
Paper: TUPCO24
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-TUPCO24
About: Received: 03 Sep 2025 — Revised: 09 Sep 2025 — Accepted: 10 Sep 2025 — Issue date: 20 Jan 2026
TUPCO31
R&D of an ultrafast X-ray beam size monitor for SuperKEKB
435
SuperKEKB is a high luminosity electron-positron collider that aims to achieve an instantaneous luminosity ten times higher than the present world luminosity record by SuperKEKB itself. However, stable operation is hampered by a phenomenon known as Sudden Beam Loss (SBL), where beam instability occurs within tens of microseconds, resulting in significant beam loss and triggering a beam abort. It has been suggested that a fast increase in beam size may accompany SBL events. To study this rapidly evolving beam size instability and to gain deeper insights into SBL, we are developing a new bunch-by-bunch X-ray beam size monitor. It uses a silicon strip sensor to read the synchrotron radiation from the bending magnet and can record the transverse size of all bunches arriving at least 4 ns intervals. This presentation will detail the development of the X-ray beam size monitor and report on preliminary performance tests using laser light as a proxy for synchrotron radiation.
Paper: TUPCO31
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-TUPCO31
About: Received: 01 Sep 2025 — Revised: 08 Sep 2025 — Accepted: 10 Sep 2025 — Issue date: 20 Jan 2026
TUPMO07
Beam size measurement at SBL in SuperKEKB
467
Sudden beam loss (SBL) is one of the obstacles to improving the luminosity of SuperKEKB. SBL cause damage to collimators and other accelerator components, QCS quench, and large background to the Belle II detector. It also causes beam abort and prevents the accumulation of high currents. Therefore, it is an important issue to investigate and resolve the causes of SBL events. In order to investigate the causes of SBL events, we measured the beam profile at the moment abort due to SBL using three different cameras and found that the beam size was larger than at the moment of abort due to other causes. This paper summarizes the results of the beam size measurements made as part of the investigation into the cause of the SBL.
Paper: TUPMO07
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-TUPMO07
About: Received: 03 Sep 2025 — Revised: 09 Sep 2025 — Accepted: 09 Sep 2025 — Issue date: 20 Jan 2026
TUPMO10
Passive Transverse Beam Profiler for Real-Time Monitoring for FLASH radiotherapy
479
Real-time beam monitoring is essential for enhancing the efficacy and reliability of radiotherapy. FLASH radiotherapy has shown a strong potential in improving treatment effectiveness by delivering doses at ultrahigh dose rates (>40 Gy/s). Beam monitoring at FLASH is challenging, as existing devices like Ionization chambers face saturation. We are developing an all-optical monitor for real-time transverse beam profile measurements in the treatment beam delivery zone. As the therapeutic beam must inherently traverse the ambient air path from the nozzle to the patient, the monitor passively captures beam-induced fluorescence along its trajectory without affecting the beam. This contribution present proof-of-concept measurements with 10.8–28 MeV protons at MC40 Cyclotron at University of Birmingham for 1 to 25 nA beam current, achieving a temporal resolution of up to 10 ms, and compared with beam size measurements with RCF. The fluorescence intensity exhibits a linear response to beam current, suggesting its potential for dose prediction after calibration. This work also discusses the challenges and potential for improvement for FLASH radiotherapy systems.
Paper: TUPMO10
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-TUPMO10
About: Received: 29 Aug 2025 — Revised: 04 Sep 2025 — Accepted: 05 Sep 2025 — Issue date: 20 Jan 2026
TUPMO13
Development of low density materials for beam intercepting instruments
491
Materials with a minimal interaction with particle beams are widely used in accelerators in interceptive instruments such as screens, secondary emission grids and wire scanners. Material damage limits are already exceeded in energy frontier and high brightness machines. A new generation of ‘low density’ materials with nano-structures are becoming available at scales of interest for use in beam instrumentation. Specifications are increasingly of use but still with fundamental issues that limit their application. This paper will demonstrate the potential for this class of materials for beam intercepting materials. It will outline the current limitations and ongoing research to overcome them both in the short and long-term.
Paper: TUPMO13
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-TUPMO13
About: Received: 02 Sep 2025 — Revised: 08 Sep 2025 — Accepted: 08 Sep 2025 — Issue date: 20 Jan 2026
TUPMO19
Current status of developing pepper-pot emittance monitor for high-intensity ion beam
505
The experiment to measure the Electric Dipole Moment (EDM) of Francium (Fr) is in progress by Center for Nuclear Study (CNS), UTokyo. Fr is produced via a nuclear fusion reaction by bombarding a gold target with oxygen-18 beam, requiring a beam intensity of 18 eμA or higher. However, the transport efficiency of the current beam line decreases to 66 % when the beam intensity exceeds 10 eμA. To address this issue, we are developing a pepper-pot emittance monitor (PEM) optimized for high-intensity beams. The improvements include locating the camera far from the beam line to minimize radiation damage, achieving a distance 4.1 m while maintaining the position error of 0.13 mm. Additionally, we conducted beam tests to verify measurement errors and found the results were consistent with the measurement errors estimated from the PEM structure. Furthermore, the beam shutter time 0.27 was estimated to be acceptable up to the beam power 1000 W to prevent PEM overheating.
Paper: TUPMO19
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-TUPMO19
About: Received: 03 Sep 2025 — Revised: 06 Sep 2025 — Accepted: 10 Sep 2025 — Issue date: 20 Jan 2026
TUPMO28
Overview and status of beam diagnostics for the injector linac of the Siam Photon Source
536
The Synchrotron Light Research Institute (SLRI) operates the SPS-I facility located in Nakhon Ratchasima, Thailand, which provides synchrotron light for various scientific and industrial applications. The linac injector, serving as the primary injector, is responsible for electron beam bunching and acceleration to 40 MeV, after which the beam is transported to the booster ring via the Low-Energy Beam Transport line (LBT). To ensure optimal beam quality and efficient transport, various beam instrumentation devices are installed along the linac injector and LBT for diagnostics and monitoring. This contribution presents an overview of the beam instrumentation used to measure beam current, transverse profiles, and energy profiles, serving as a fundamental reference for future beam optimization and performance improvements of the SPS-I linac injector system.
Paper: TUPMO28
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-TUPMO28
About: Received: 29 Aug 2025 — Revised: 05 Sep 2025 — Accepted: 10 Sep 2025 — Issue date: 20 Jan 2026
TUPMO39
Nanostructured targets for advanced beam diagnostics
562
Transverse beam diagnostics with standard imaging techniques represent a challenge for next-generation accelerators and colliders due to the extremely small beam sizes, and X-ray interferometry offers an interesting method to overcome this challenge. In this regard, the X-ray Heterodyne Near Field Speckles (X-HNFS) technique has successfully been used to resolve few-micrometer beam sizes and at the same time attain a full 2D beam reconstruction. The method relies on diffracting the emitted X-ray radiation off a water suspension of spherical nanoparticles, which however pose several limitations for the full exploitation of the technique during normal operations. In this contribution we report on recent advances in the development of solid targets based on nanostructured materials with characteristics compatible with accelerator requirements. We present preliminary numerical and experimental results on the target design, prototyping and testing. Emphasis is given to the application as a transverse beam size monitor in the framework of the Feasibility Study of the Future Circular Collider (FCC) at CERN.
Paper: TUPMO39
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-TUPMO39
About: Received: 03 Sep 2025 — Revised: 07 Sep 2025 — Accepted: 11 Sep 2025 — Issue date: 20 Jan 2026
WEPCO12
Development of a rectangular diagonal cut-plane BPM for the CSNS-II injection upgrade
645
As part of the CSNS-II upgrade, an improved injection scheme will be implemented to mitigate the space charge effect. To precisely measure the transverse beam position during injection, painting, and storage in the Rapid Cycling Synchrotron (RCS), a large-aperture (260 mm × 180 mm) Beam Position Monitor (BPM) is essential. The rectangular cut-plane BPM was selected for its excellent linearity over a large area and high signal-to-noise ratio (SNR). Due to limited space in the injection section, the BPMs must be integrated into the AC steering magnet. To prevent thermal heating from eddy current flow, a rib structure has been incorporated into the BPM's outer body. The BPM was designed using numerical simulation codes and subsequently manufactured. This paper details the simulation, design, and calibration results of the diagonal cut-plane BPM.
Paper: WEPCO12
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-WEPCO12
About: Received: 03 Sep 2025 — Revised: 08 Sep 2025 — Accepted: 10 Sep 2025 — Issue date: 20 Jan 2026
WEPCO14
Spiral beam position monitor for heavy ion beams
649
Our heavy ion beams are slow, short, and thick. For such beams, spiral beam position monitors(BPMs) are expected to provide good linearity and multiple information readouts despite their small size. At the RIKEN Nishina Center, various ion beams are accelerated using linacs and cyclotrons. However, the beams handled are slow enough compared to relativistic speeds, the bunch length is only about the same as the electrode size, and the beam diameter may be close to the electrode spacing. Conventional “diagonal cut” or “cosine two-theta cut” (for quadratic moments) BPMs produce deviations in wave height*. To solve this problem, it is expected that the wave height deviation can be eliminated by cutting the electrode in a spiral shape. Furthermore, by cutting in a spiral shape, multiple cuts can be placed in one BPM, and it is expected that beam intensity, horizontal position, vertical position, and second moment can be read out at a single location. The performance shown by simulations of the spiral BPM and the development of a prototype will be presented.
Paper: WEPCO14
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-WEPCO14
About: Received: 03 Sep 2025 — Revised: 09 Sep 2025 — Accepted: 10 Sep 2025 — Issue date: 20 Jan 2026
WEPCO22
High-resolution longitudinal beam diagnostics with a Fast Faraday Cup at the UNILAC accelerator
666
At the heavy ion accelerator UNILAC at GSI Helmholtz Center for Heavy Ion Research in Darmstadt, measurements were carried out with a Fast Faraday Cup (FFC) in order to precisely measure the time structure of the particle beam. The FFC offers a highly accurate time-resolved recording of the charge distribution along the longitudinal beam profile. The data obtained in combination with a dipole magnet is used to determine the longitudinal phase space and emittance of the beam. After analyzing the measurement results, the method is integrated into the regular beam diagnostics to ensure continuous monitoring and control of the particle beam during operation. Measurement procedure and results are presented.
Paper: WEPCO22
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-WEPCO22
About: Received: 04 Sep 2025 — Revised: 11 Sep 2025 — Accepted: 11 Sep 2025 — Issue date: 20 Jan 2026
WEPCO28
Measurement of two beams positions with button BPM
687
Modern BPM processors utilize digital processing of the beam induced signals. The information on the signal amplitudes is used for the delta over sum calculation of the beam position, while the readily available phase information is usually discarded. We have experimentally tested measurement of the individual positions of two beams propagating in the common beampipe utilizing both phase and amplitude data. The proposed method can be used for the energy recovery linacs and colliders.
Paper: WEPCO28
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-WEPCO28
About: Received: 14 Aug 2025 — Revised: 07 Sep 2025 — Accepted: 10 Sep 2025 — Issue date: 20 Jan 2026
WEPCO40
Fibre-Coupled Oscillator-Driven Electro-Optic Spectral Interferometry as a Longitudinal Bunch Profile Monitor
707
Electro-optic (EO) diagnostics offer non-destructive methods to resolve the longitudinal charge profile of highly relativistic bunches without the need for complex calibrations or ambiguous phase recovery techniques. The most common technique, EO spectral decoding (EOSD), is favoured for its simplicity, reliability, and straightforward output interpretation, however its resolution is constrained to the geometric mean of the transform-limited and chirped probe laser durations. We have introduced a new technique utilising spectral interferometry (EOSI), which overcomes this limitation by adding a single optical element to an EOSD setup, with successful measurements shown previously on the CLARA accelerator at Daresbury Laboratory. To further explore this technique, we have performed EOSI on the CLEAR accelerator at CERN (160-200 MeV, 15-150 pC and 0.2-1.5 ps RMS) utilising a nJ oscillator and optical fibre-coupled transport. Our results highlight the potential for low power, turn-key operation and flexible integration of EOSI systems for single-shot ultrashort bunch length and arrival time monitoring.
Paper: WEPCO40
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-WEPCO40
About: Received: 03 Sep 2025 — Revised: 07 Sep 2025 — Accepted: 11 Sep 2025 — Issue date: 20 Jan 2026
WEPMO03
Smith-Purcell and transition radiation based charged particle beam diagnostics for the femtosecond-range
715
We will give an overview of the Smith-Purcell and transition radiation based longitudinal diagnostic methods employed at the ARES (Accelerator Research Experiment at SINBAD) linear accelerator to characterize femto-second long electron bunches. The Smith-Purcell radiation mechanism has been studied for the case of metallic gratings, but not much experimental data has been published yet with respect to dielectric gratings as charged particle beam diagnostic devices. We expect a number of advantages in the detection of the radiation at the substrate side and the spectral properties of the radiation tailored by the geometric shape of the grating structures. Due to the advances in lithographic techniques dielectric gratings can be produced with optical wavelength periodicities and the shapes can be controlled with nano-meter precision. For femto-second bunch lengths the coherence of transition radiation starts to reach the near-infrared to optical regime. This opens up the possibility of characterizing the spectrum with readily available high sensitivity semi-conductor based detectors to draw conclusions on the form factor and measure bunch lengths.
Paper: WEPMO03
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-WEPMO03
About: Received: 06 Sep 2025 — Revised: 17 Sep 2025 — Accepted: 17 Sep 2025 — Issue date: 20 Jan 2026
WEPMO09
Online position conversion factor calibration study for BPM system
736
Transverse beam position is one of the most critical parameters in accelerator commission and operation. As non-invasive diagnostic devices, beam position monitors (BPMs) are the main “workhorse” in accelerators, providing beam center of mass position information. The position conversion factor (K-factor) of BPM systems constitutes a fundamental determinate of measurement accuracy. While precision calibration traditionally relies on moveable calibrate platforms, the prohibitive cost of equipping each BPM with a dedicated two-dimensional calibration platform remains a widespread practical constraint. In this paper, an innovative online calibration method that synergizes machine learning with beam response matrix analysis to achieve per-BPM K-factor determination is introduced. The preliminary beam experiments have been carried out at Shanghai Soft X-ray Free-Electron Laser (SXFEL) facility. The proposed method offers a robust and resource-efficient calibration solution, particularly advantageous for cavity BPM systems where conventional approaches such as theoretical calculation and offline wire scanning, fail to provide reliable results.
Paper: WEPMO09
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-WEPMO09
About: Received: 03 Sep 2025 — Revised: 10 Sep 2025 — Accepted: 10 Sep 2025 — Issue date: 20 Jan 2026
WEPMO12
Digital signal processing improvements of the SPIRAL2 beam position monitors at low intensity
743
The SPIRAL2 accelerator, designed for high intensity beams (up to 5 mA), needs to evolve for low intensities in order to reach the requirements of the S3 experimental room. This means increasing the operating range of diagnostic monitors including the Beam Position Monitors (BPM). Twenty BPM are installed in the warm sections of the linac to measure positions, ellipticities and phases. The digital processing of the BPM acquisition has been modified to operate at low intensity. This was done by improving the signal-to-noise ratio with an increase of the averaging resolution, an improvement of the channel equalisation system and with a deduction of parasitic signals induced by the surrounding equipment. The process was also modified to operate with chopper frequencies between 1 Hz and 1 kHz. A new BPM interface, with tables and graphical displays in order to control beam phases and energies in the linac, is now available. These new developments and measurement results in laboratory and with SPIRAL2 beams are presented, which show good results with a low intensity down to 1 µA.
Paper: WEPMO12
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-WEPMO12
About: Received: 29 Aug 2025 — Revised: 05 Sep 2025 — Accepted: 10 Sep 2025 — Issue date: 20 Jan 2026
WEPMO20
Study of a novel eight electrodes RF pickup
766
The IFMIF-DONES facility located at Escúzar in Spain will consist of an accelerator delivering 125 mA of 40 MeV deuterons onto a Lithium target. At the last part of the accelerator, when the beam footprint is almost shaped, different beam diagnostics are considered. In order to protect the machine against changes of the beam and give a safe interlock, a novel RF pickup made of eight electrodes is designed. This RF pickup is designed with the objective to sense displacements of the beam centroid as changes of the beam profile. In this paper a preliminary study is presented based on an analytical and CST simulation approach. Both approaches, considering pencil and real beams from TraceWin simulations, are compared. Next, a sensitivity study of how different parameters affect the response is performed in CST simulations. This work has been carried out within the framework of the EUROfusion Consortium.
Paper: WEPMO20
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-WEPMO20
About: Received: 01 Sep 2025 — Revised: 08 Sep 2025 — Accepted: 08 Sep 2025 — Issue date: 20 Jan 2026
WEPMO27
Transverse and longitudinal beam diagnostics and characterizations at IUAC-high current injector
792
The High Current Injector features normal-conducting RF Linac structures intended to accelerate various ion species with a mass-to-charge ratio of up to 6, achieving a maximum output energy of 1.8 MeV/u. It can deliver an intense analyzed beam up to 100pnA at the target. To preserve the beam quality at the target and to improve the performance of RF cavities and beam transmission, both destructive and non-destructive, fast and precise transverse and longitudinal beam diagnostics (including FFCs and CPOs for phase space and ToF measurements) are deployed in LEBT, MEBT and HEBT section of HCI. The beam energy was validated through the existing Surface Barrier Detector measurement setup. Recently, during 20Ne9+ beam test, we observed a notable energy spread of approximately 1%, which led to pronounced debunching and a complete loss of the necessary signal component in the downstream BPMs. To mitigate the energy spread, slits have been installed at the image plane of the fourth achromatic bending magnets, and it was observed that optimally adjusting the slits can reduce the spread by over fifty percent. This paper will present the latest measurements, challenges and future plans.
Paper: WEPMO27
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-WEPMO27
About: Received: 03 Sep 2025 — Revised: 08 Sep 2025 — Accepted: 09 Sep 2025 — Issue date: 20 Jan 2026
WEPMO28
Optimisation of a fibre-based two-colour balanced optical cross-correlator
795
As part of the ongoing Full Energy Beam Exploitation (FEBE) upgrade to the Compact Linear Accelerator for Research and Applications (CLARA) at the Daresbury Laboratory, UK, few-femtosecond optical synchronisation between the new Ti:Sapphire terawatt FEBE laser and the Er:Yb optical master oscillator (OMO) is required for user experiments. To achieve this, a fibre-based two-colour balanced optical cross-correlator (BOXC) using waveguided periodically-poled lithium niobate (PPLN) crystals is being developed. A fibre-based BOXC could have greater sensitivity to timing jitter between two lasers than traditional free-space devices. In this manuscript, the design of the fibre-based two-colour BOXC is presented. The effect of pulse chirp on the sensitivity of the BOXC is investigated, and plans for optimising the design of the BOXC are discussed along with plans for integrating the fibre-based BOXC into the optical synchronisation network at Daresbury.
Paper: WEPMO28
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-WEPMO28
About: Received: 03 Sep 2025 — Revised: 05 Sep 2025 — Accepted: 10 Sep 2025 — Issue date: 20 Jan 2026
WEPMO37
Preliminary radiation hardness characterization of ultra-broadband direct THz detectors based on Schottky diodes and GaAs TeraFETs
825
Many currently operating and future FELs can generate radiation at megahertz repetition rates, requiring an ultra-broadband, compact, robust & fast (response time at least on a single-digit nanosecond scale) diagnostic tool. We develop ultrafast-operating terahertz detectors based on Schottky diodes and GaAs field-effect transistors (TeraFETs) that operate at room temperature. Here, we present the preliminary radiation hardness characterization of these detectors. Promising results demonstrate the ability of these detectors to be commissioned at accelerator facilities for longitudinal beam diagnostics.
Paper: WEPMO37
DOI: reference for this paper: 10.18429/JACoW-IBIC2025-WEPMO37
About: Received: 03 Sep 2025 — Revised: 06 Sep 2025 — Accepted: 09 Sep 2025 — Issue date: 20 Jan 2026