IBIC2026 - 15th International Beam Instrumentation Conference

30 Aug 2026, 00:00 → 3 Sept 2026, 13:00 Canada/Pacific

Rainbow Theatre (Whistler Conference Centre)

Marco Marchetto (TRIUMF)

About the Conference

 

Registration is now open! Please register here.

The International Beam Instrumentation Conference (IBIC) is dedicated to exploring the physics and engineering challenges of beam diagnostic and measurement techniques for particle accelerators worldwide. The IBIC series rotates on an annual basis through the three regions of:

• Europe, Middle East and Africa
• Americas (North and South)
• Asia & Australia

 

In 2026, IBIC will come to North America and take place in the beautiful resort village of Whistler, BC, Canada between August 30 - September 3, 2026.

We look forward to welcoming you to Whistler!

IBIC2026 Sponsors

 

Past Conferences

IBIC2025 - Liverpool, UK

IBIC2024 - Beijing, China

IBIC2023 - Saskatoon, Canada

IBIC2022  - Kraków, Poland

IBIC2021 - Pohang, South Korea, remote 

IBIC2020 - Santos, Brazil, remote 

IBIC2019 - Malmo, Sweden 

IBIC2018 - Shanghai, China 

IBIC2017 - Grand Rapids, Michigan, USA 

IBIC2016 - Barcelona, Spain 

IBIC2015 - Melbourne, Australia 

IBIC2014 - Monterey, California, USA 

IBIC2013 - Oxford, UK  

IBIC2026 Brochure_Final.pdf

IBIC2026_Program.pdf

IBIC Logo-01.png

IBIC Poster V1.pdf

Sunday 30 August

15:00 Registration and Welcome Reception

18:00 Welcome Reception (Grand Foyer, WCC)

Monday 31 August

08:00 Registration

Opening Welcome

Convener: Marco Marchetto (TRIUMF)

Invited Oral: Invited Talk (Conny Hoehr)

1 Optical fibre detectors for medical applications with accelerators

Optical fibre-based detectors offer unique opportunities for radiation measurement at accelerators, including medical-based applications, combining small size, flexibility, real-time response, and immunity to electromagnetic interference. This presentation focuses on the development and application of optical fibre sensors, including scintillating fibres and fibre Bragg gratings (FBGs), for dosimetry, beam monitoring, alignment, and characterization of accelerator beams used in radiotherapy and medical isotope production. In proton therapy and FLASH radiotherapy, fibre-based systems are being investigated for high-resolution, minimally perturbing measurements of dose and beam parameters, including the contribution of secondary radiation. FBG sensors are also being developed for monitoring temperature and pressure in isotope production targets, providing valuable information for understanding and optimizing target performance under high-power irradiation. This work brings together accelerator physics, detector development, medical physics, and radiation effects to establish robust optical fibre technologies for next-generation accelerator-based medical applications.

Speaker: Cornelia Hoehr (TRIUMF)

09:40 IBIC Prize

MC03 Beam Position Monitors

Monday Morning

2 Beam instrumentation challenges for the electron-ion collider project

With the Relativistic Heavy Ion Collider (RHIC) ceasing its operation in February 2026, the Electron-Ion Collider (EIC) project at the Brookhaven National Laboratory (BNL) will be the only high-energy particle collider in North America, foreseen to start operating in 2035. To provide the ambitious electron and hadron ring beam parameters to achieve the required luminosity, collision energies and spin polarization, a suite of reliable and cost-effective beam instruments (BI) is neccessary. This presentation will give a short overview of the EIC beam instrumentation suite and points out a few, particular challenging examples, such as the beam position monitor systems, explaining the design choices, methodology, and tools used. While there is no EIC beam, some instrumentation design procedures have been verified with measured beam data at RHIC to give confidence in the EIC BI design methods and tools.

Speaker: Manfred Wendt (Brookhaven National Laboratory)

10:20 Break

10:50 Faraday Cup Award / Transverse Profile and Emittance Monitors - Kevin Jordan

MC04: Transverse Profile and Emittance Monitors

Convener: Kevin Jordan (Thomas Jefferson National Accelerator Facility)

3 Full-cycle, noninvasive emittance monitoring with the beam gas curtain monitor at the LHC

The high intensity and wide energy range of the Large Hadron Collider (LHC), further extended by its high-luminosity upgrade, set great challenges on beam diagnostics. The Beam Gas Curtain (BGC), installed on Beam 1 in 2023, addresses these challenges with a non-invasive profile monitor exploiting the fluorescence induced by the beam in a thin supersonic gas curtain. This contribution reviews the operational experience gained with the instrument, presenting emittance measurements performed continuously over the full machine cycle with proton and lead ion beams, and their cross-validation against the other LHC transverse diagnostics. The most recent developments are then described: the optimisation of the gas curtain width, which improves the spatial resolution, and the first tests with nitrogen, whose higher fluorescence yield is offset by space-charge broadening. The perspectives for the second instrument foreseen for LHC Beam 2 are finally outlined.

Speaker: Daniele Butti (European Organization for Nuclear Research)

4 Development and beam observations of an ultra-fast bunch-by-bunch X-ray beam size monitor at SuperKEKB

High-luminosity electron–positron colliders such as SuperKEKB operate with high bunch currents and a large number of bunches in collision. Under these conditions, various beam instabilities can arise and limit beam performance. Investigating such phenomena requires diagnostic instruments capable of resolving beam properties on a bunch-by-bunch timescale. In particular, identifying bunch-dependent behavior associated with collective effects requires direct beam size measurements with nanosecond-level temporal resolution. We have developed a new ultra-fast X-ray beam size monitor for SuperKEKB based on synchrotron radiation from a bending magnet combined with coded-aperture optics and a silicon strip detector. The detector signals are digitized at 2.7 Gsps, providing vertical beam size information for each bunch in the main ring with a minimum time separation of approximately 4 ns. The system has been installed in the SuperKEKB main ring and used for beam observations during the 2025 and 2026 operation periods. Bunch-by-bunch beam size data have been successfully acquired under a variety of accelerator conditions, enabling detailed studies of beam size variations along bunch trains. This presentation reports the development and commissioning of this new monitor, together with beam observation results and their analysis, demonstrating the capability of this diagnostic system for studying bunch-dependent beam behavior at SuperKEKB.

Speaker: Riku Nomaru (The University of Tokyo, High Energy Accelerator Research Organization)

11:50 Group Photo

12:00 Lunch (not included in registration)

Lunch is not provided in the registration fee. Attendees are encouraged to visit the many restaurant locations in the Village of Whislter

MC04: Transverse Profile and Emittance Monitors

Convener: Kenichirou Satou (High Energy Accelerator Research Organization)

5 Betatron radiation as a dual diagnostic for electrons and photons in plasma accelerators

Betatron radiation generated by relativistic electrons oscillating in plasma wakefields constitutes a powerful, non-invasive diagnostic for both electron beams and the emitted photon radiation in plasma accelerators.
The spectral, angular, and statistical features of the radiation encode key information about electron dynamics, enabling single-shot reconstruction of electron beam parameters, such as oscillation amplitude, divergence, and normalized emittance.
In addition, recent studies have shown that shot-noise-induced spectral fluctuations in betatron radiation provide direct access to the temporal structure of the emitted XUV pulses, allowing single-shot, femtosecond-scale electron and photon diagnostics.
Complementary experimental and modeling efforts further demonstrate how detailed analysis of betatron spectra and angular distributions can be exploited to characterize both the electron phase space and the lateral coherence of the emitted radiation.
Together, these results establish betatron radiation as a versatile diagnostic tool that simultaneously probes electron and photon beam quality in plasma-based acceleration schemes.

Speaker: Alessandro Curcio (Sapienza University of Rome)

6 Large-diameter carbon nanotube fiber for H-/proton beam diagnostics: fabrication, test and implementation at CSNS accelerator

Carbon nanotube fibers are a promising alternative to traditional materials used in accelerator beam diagnostics due to their high thermal conductivity, mechanical strength, and radiation resistance. A novel large-diameter carbon nanotube (CNT) fiber has been recently fabricated and produced based upon vacuum annealing purification. We have optimized the fabrication process to produce continuous CNT fibers (100 m) with consistent diameter (100 μm, ±5%) and enhanced tensile strength (1.8 GPa), specifically tailored for high-intensity accelerator applications. Extensive bench tests and thermal endurance evaluations were carried out at IHEP to verify the fiber’s performance under simulated beam operating conditions. The CNTF-based multi-wire scanners were subsequently developed and installed in the China Spallation Neutron Source (CSNS), enabling stable profiling of long-pulse H⁻ beams (80 MeV, 15 mA, ~600 μs). Beam test results indicate that the large-diameter CNT fibers deliver stable, reliable profile measurements with higher signal output than conventional carbon fibers. This paper details the fabrication strategy, mechanical and thermal property tests, beam test results, and the experience of successful implementation at CSNS.

Speaker: chunjie xie (Institute of High Energy Physics)

7 Polychromatic synchrotron interferometer for HALF: single-shot two-dimensional beam profiling

This paper presents a novel polychromatic synchrotron interferometer specifically designed to meet the stringent single-shot, two-dimensional beam diagnostic requirements of fourth-generation diffraction-limited light sources like the Hefei Advanced Light Facility (HALF). The system overcomes the limitations of conventional sequential and single-projection methods by enabling complete transverse beam profile reconstruction from a single exposure. Its core innovation utilizes a color CCD's Bayer filter array to simultaneously record broadband interference fringes across red, green, and blue channels, each corresponding to a distinct projection angle of the beam via a tailored multi-slit mask. This provides parallel spatial coherence measurements at multiple effective spatial frequencies and orientations. To accurately extract beam parameters from the polychromatic signal, a broadband visibility integral inversion method is developed, accounting for the source spectrum and system response. The instrument has been successfully validated through beam experiments at the Hefei Light Source (HLS-II). Using a multi-slit mask with color filters, the system demonstrated single-shot acquisition of beam projections at 0°, 45°, and 90°, from which the full two-dimensional transverse profile was reconstructed. This work provides a validated, high-throughput, and non-invasive diagnostic solution for real-time beam characterization at HALF and other ultra-low-emittance facilities.

Speaker: Xinru Gao (University of Science and Technology of China)

14:40 Break

MC03: Beam Position Monitors

Convener: Carsten Welsch (University of Liverpool)

8 Beam position monitor electronics for ALS-U using RFSOC

The ALS has been running with an in-house designed Beam Position Monitor for over 10 years. A new design has been developed for the ALS-U project. It includes 8 inputs per pizza-box chassis, an improved Pilot Tone generation for the two button sets, a modular packaging for upgrades and adapting to other machine RF, and improved performance.

The ALS-U BPM uses an AMD Gen3 RFSOC, which provides eight 5GSPS 14-bit ADC and 10GSPS 14-bit DACs. Increasing the ADC sampling rate from the original 117MHz of the ALS design to the new 5GSPS simplified the design of the Analog Front End. The on-board DACs eliminated the separate chassis used at ALS for PilotTone generation, and is more flexible than the previous PLL design.

The RFSOC provides a Digital UP & Down Conversion blocks; the ADC data rate to a 40x DDC rate that is easily processed by the FPGA programmable logic, while a 40x DUC is used for the 2-Tone Pilot Tone Generation of the DAC to reduce table length. The current firmware which handles position generation for two button sets uses less than half of the available FPGA resources.

A full chassis with 8 AFE and 2 PilotTone modules has been built, and tested in both the lab and at ALS. A second chassis is being built. Production builds start this year to support AR commissioning in 2027.

Speaker: Michael Chin (Lawrence Berkeley National Laboratory)

9 Upgrading Front-End XBPMs for Diamond-II

The upgrade of Diamond Light Source to the 4th generation storage ring, Diamond-II, introduces significant changes in the white photon beam properties. Upgrades to the existing XBPM hardware are underway to accommodate increased beam power while maintaining high position sensitivity across beamlines. XBPM blade geometries and positions were optimised using Synchrotron Radiation Workshop (SRW) simulations, considering blade damage thresholds, potential shadowing from upstream components, and beam position sensitivity. Further optimisation was performed for APPLE insertion device beamlines to understand the impact variable polarisations will have on the photon beam profile and therefore the XBPM measurements. The upgraded XBPMs have been installed and commissioned on Diamond front ends. To further improve performance, upgrades to the readout electronics are planned. These upgrades are intended to support future integration of photon beam position measurements with the fast orbit feedback infrastructure as well as providing synchronisation with the Electron Beam Position Monitors (EBPMs). This contribution presents the XBPM hardware upgrades, commissioning results, and ongoing developments towards a unified beam position monitoring system for Diamond-II.

Speaker: Claire Houghton (Diamond Light Source)

10 Development and characterization of a high-resolution re-entrant cBPM system at the ATF linac

A re-entrant cavity beam position monitor (cBPM) has been designed using CST Studio Suite electromagnetic simulations to provide high-resolution spatial measurements for future colliders. This model, operating at 1.631 GHz, offers improved theoretical performance compared to previous prototypes by increasing the normalized shunt impedance and the loaded quality factor, which enhance sensitivity and signal duration, respectively. The design incorporates commercial feedthroughs and achieves low coupling between orthogonal ports, minimizing cross-talk. The prototype was manufactured with tolerances of 50 um, and its radio-frequency parameters were characterized to evaluate performance prior to beam tests.

A dedicated readout system, featuring an analog down-conversion stage followed by a digital down-conversion algorithm, was developed and tuned to the cBPM operating frequency to reconstruct beam position via a calibration procedure. The broadband nature of the signals allows filtering of the monopole mode at the dipole frequency, enabling extraction of X, Y positions, and reference signals from a single cBPM. The complete system (cBPM and readout chain) was installed at the end of the Accelerator Test Facility Linac. This setup underwent full characterization to evaluate dynamic range, linearity, and spatial resolution. Finally, the measurement system limitations are evaluated to establish the reach of the cBPM system and its potential for future collider applications.

Speaker: Laura Pedraza (Instituto de Física Corpuscular)

11 Development of a novel wide-bandwidth pickup for intrabunch measurements

This paper presents the design of a novel semi-coaxial stripline pickup for wide-band beam diagnostics. Four electrodes inside the beam pipe form a quasi-coaxial transmission line that improves electromagnetic field control and provides a smooth impedance transition, mitigating the bandwidth limitations and impedance discontinuities typical of conventional stripline pickups. Electromagnetic simulations performed using CST Studio Suite demonstrate excellent impedance matching with a characteristic impedance $Z_0$ of $50\,\Omega \pm 0.2\,\Omega$. The pickup exhibits low reflections ($S_{11} < -40$ dB up to 6 GHz) together with a flat $S_{21}$ transmission response over a bandwidth exceeding 6 GHz. A prototype with achievable mechanical tolerances was built to validate the simulations. The paper compares the simulated and measured performance and discusses possible improvements for future design iteration.

Speaker: Giusy Valeria Passarelli (European Organization for Nuclear Research)

Monday Poster Session 1

12 Design and planned commissioning of the ARIEL beam loss monitors

The Advanced Rare IsotopE Laboratory (ARIEL) presents a unique challenge for beam loss monitoring due to the simultaneous operation of two closely spaced driver beamlines. ARIEL consists of a 500 MeV proton beamline and a 30 MeV electron beamline that are separated by only 1 m in certain sections, requiring reliable discrimination of beam losses originating from each beamline. Accurate identification of beam spills is essential for effective machine protection while minimizing unnecessary beam interruptions. To address this challenge, the ARIEL beam loss monitoring system has been designed using a combination of complementary detector technologies, including optical fibre–based monitors, long ionization chambers, and scintillating detectors. The design of the beam loss monitoring system, the expected performance for distinguishing beam losses between the two beamlines, and the commissioning plans will be presented.

Speaker: Martin Alcorta Moreno (TRIUMF)

13 Monte Carlo simulations of LHC beam loss ionization detectors

The Beam Loss Monitoring (BLM) system of the Large Hadron Collider (LHC) at CERN has the main functionality to actively protect the LHC superconductive magnets against quenches due to energy depositions from beam-induced losses and prevent damage of other sensitive equipment. For this reason, the LHC is presently equipped with more than 3500 ionization chambers 0.5 m-long distributed along the accelerator and downstream selected elements. The standard LHC-type ionization chambers are very sensitive and provide a high dynamic range. However, at certain locations, such as downstream collimators, maximum beam loss specifications are above the saturation limits of the detector. For this reason, the use of a smaller version of the ionization chamber providing lower sensitivity is being investigated. This contribution discusses the differences in the detector response from Monte Carlo simulations between the standard LHC ionization chamber and its smaller version.

Speaker: Belen Salvachua (European Organization for Nuclear Research)

14 First results of laser wire transverse profile monitor at LANSCE

A prototype laser wire scanner (LWS) was used to measure horizontal and vertical profiles of the 750-keV H- beam in the Los Alamos Neutron Science Center (LANSCE) accelerator front end under two beam optics configurations. At some scan positions, the electron-detector response was bipolar rather than the expected single negative pulse. Profiles were reconstructed using both negative-lobe integrals and integrals of two-sided Gaussian fits. The two methods indicated modest broadening from Beam Optics A to B, 11–12% horizontally and 7–9% vertically in laser-angle coordinates. These changes were substantially smaller than the TRACE 2D predictions. The results demonstrate the feasibility of noninvasive transverse profiling at LANSCE while identifying scan calibration and electron-collection effects as priorities for further study.

Speakers: Heather Andrews (Los Alamos National Laboratory), Martin Kay (Los Alamos National Laboratory)

15 Impedance optimization of the SPS-II beam scraper

The vertical beam scraper for the Siam Photon Source II (SPS-II) storage ring is designed for beam halo cleaning and protection of narrow-gap insertion devices. Compared with the horizontal scraper, the vertical configuration requires a wider blade for effec-tive halo interception, resulting in a more pronounced geometric discontinuity and a potentially larger con-tribution to the beam coupling impedance. This work presents the electromagnetic optimization of the verti-cal scraper using the CST Studio Suite Wakefield Solver. The blade dimensions, chamber aperture, and transition geometry were systematically modified within practical mechanical constraints. The resulting designs were evaluated in terms of longitudinal im-pedance, loss factor, beam-induced power, and trans-verse wakefield effects to identify a configuration that minimizes the scraper impedance while preserving the required mechanical functionality.

Speaker: Siriwan Jummunt (Synchrotron Light Research Institute)

16 A study of straw detector saturation effects with a 440 GeV/c bunched proton beam at CERN's HiRadMat facility

Part of the ongoing effort to upgrade the intensity of CERN beamlines in the North Experimental Area is examining technologies for their potential use in a radiation-hard transverse beam profile monitors. One such technique is to use a straw detector, potentially operated at a voltage where charge amplification does not occur. We show results from an experiment with a 4.82 mm diameter thin-walled straw detector using a gas mixture of 50/50 $\text{Ar}/\text{CO}_2$ at atmospheric pressure carried out at the High-Radiation to Materials (HiRadMat) facility at CERN. The beam used was a 440 GeV/c bunched proton beam at intensities up to 2.1e11 particles per bunch with a bunch length of 0.37 ns. To our knowledge, a first such measurement of the time-scale of the straw signal saturation is described, made possible by the SPS sending two bunches with a delay of up to 8 $\mu\text{s}$ between them.

Speaker: Robert Larsen (European Organization for Nuclear Research)

17 A light-based detector for beam diagnostics and monitoring

This work presents a modular light-based detector platform for beam monitoring in conventional and FLASH particle radiotherapy. The system addresses limitations of current beam profilers, which often lack versatility across radiation types, dose rates, field sizes, and spatial-resolution needs. The detector is based on scintillating-fiber arrays coupled to photodiode readout electronics, enabling transverse beam-profile reconstruction without high voltage. Prototypes were developed from compact 50 × 50 mm² systems to larger 250 × 250 mm² detectors, with fiber pitches of 0.4 mm for high-resolution applications and 0.8 mm for larger-area coverage. An embedded UV calibration system corrects channel variations and compensates for radiation-induced changes. The platform connects through a single Ethernet cable and includes dedicated acquisition and analysis software. It was tested with therapeutic proton and carbon-ion beams, as well as 200 MeV electrons at PSI, CNAO, and CERN. The results show successful 2D beam-profile measurements in good agreement with reference systems, demonstrating the potential of this scalable detector for beam diagnostics, online monitoring, and QA across conventional and FLASH radiotherapy conditions

Speaker: Benoit Truc (Swiss Center for Electronics and Microtechnology (Switzerland))

18 An ionization profile monitor for transverse beam profile measurements at GSI/FAIR

A control and acquisition system for ionization profile monitor (IPM) stations at GSI/FAIR has been implemented and deployed, providing real-time, simultaneous transverse beam characterization in both planes without disturbing the beam. Built on FESA (Front-End Software Architecture), the system uses dedicated classes to manage the cameras, high-voltage control, and digital I/O. Each transverse plane uses an MCP in a chevron configuration with an attached phosphor screen, imaged by a global-shutter GigE camera. Per-frame image correction and noise filtering compensate for detector non-uniformity and degradation while masking defective pixels. Configurable estimators then extract the beam position, beam width, and profile integral from the resulting profiles. Automatic high-voltage reduction protects the detector under overload conditions. Acquisition is synchronized with the accelerator cycle via a White Rabbit timing receiver, supporting frame rates of up to 300 fps. Acquired images and computed profiles are saved per machine cycle in an XML-based format. A JavaFX operator interface provides guided setup, live visualization with historical data overlay, and expert configuration options. Designed to support multiple IPM stations at GSI/FAIR, the system is currently in operational use at SIS18 (heavy-ion synchrotron) and ESR (Experimental Storage Ring).

Speaker: Rok Hrovatin (Cosylab)

19 Beam Diagnostic Strategy for the SRF Linac Commissioning of LIPAc

Following the successful commissioning of a 5 MeV high-current deuteron beam in June 2024, the Linear IFMIF Prototype Accelerator (LIPAc) is entering a new operational phase with the integration of the superconducting RF (SRF) linac, targeting first 125 mA deuteron beam acceleration up to 9 MeV and to continuous wave from early 2027. This contribution presents the beam diagnostic strategy developed for SRF linac commissioning, guided by operational experience gained during the last beam operation commissioning phase, termed as Phase B+.
The Phase B+ campaign confirmed the beam operation procedure and the operational behaviour of Beam Diagnostic, enabling beam characterization and highlighted several limitations under high-current operation, including instabilities in Beam Position Monitors (BPM) signals, reliability constraints in profile monitors, limited redundancy in front-end electronics, and restricted spatial resolution in beam loss detection. These observations have directly informed a set of targeted upgrades implemented for the next beam operation phase, Phase C.
The upgraded system features reconfigured BPM coverage with improved signal integrity, an extended BLoM system with different detectors for enhanced loss localization, and ongoing modernization of the data acquisition architecture from VME to μTCA. Additional developments include the replacement of the material in the interceptive plates of the slits devices, in compliance with the operational requirements.

Speaker: Mukesh Dhakarwal (VERSE, IFMIF/EVEDA Integrated Project Team)

20 Beam loss monitoring and protection for the upgraded cyclotron injection system at TRIUMF

The Ion Source and Injection System transports 300 kV negative hydrogen ions from the ion source to the cyclotron injection point. While the vertical section was upgraded in 2011, recent work focused on the horizontal section, featuring new optics, advanced beam diagnostics, µ-metal shielding, enhanced vacuum systems, updated power supplies, and modernized control infrastructure. A new ion source terminal is being integrated as part of these upgrades. Given the requirement to deliver 1 mA at 300 kV, beam loss monitoring (BLM) and machine protection interlocks are critical for reliable proton beam delivery. This paper presents the commissioning and operational performance of the BLM system, including diagnostic data for beam current, position, transverse profile, and localized beam loss.

Speaker: Suresh Saminathan (TRIUMF)

21 Beam quality improvement and beam diagnostics for SuperKEKB injection in the KEK e⁻/e⁺ linac and beam transport lines

The KEK e⁻/e⁺ linac supplies, in pulse-by-pulse basis, electron beams to the SuperKEKB HER, PF, and PF-AR, and positron beams to the SuperKEKB LER. Injection into the SuperKEKB HER and LER requires highly stabilized low-emittance beams with high intensity. During beam operation, beam quality is improved and stability is maintained using approximately 160 Beam Position Monitors (BPMs), which are installed from the linac to the BT lines, three synchrotron radiation monitors, and diagnostic beams that are sampled and extracted to a dedicated beam line.This report describes a status of these monitors and the beam tuning methods. It also presents methods for bunch-length measurement and phase-drift correction using existing monitors and accelerating structures.

Speaker: Fusashi Miyahara (High Energy Accelerator Research Organization)

22 BeamNetUS: accelerating beam-based research

BeamNetUS is a collaborative user network of twelve beam test facilities spanning six U.S. Department of Energy national laboratories, dedicated to advancing particle accelerator research, technology development, and applications. Through an annual open call for proposals, BeamNetUS invites exploratory research aimed at seeding new collaborations and fostering innovation across the accelerator community and beyond. Users gain access to state-of-the-art experimental capabilities, specialized expertise, and a diverse suite of distributed resources. The pilot run in 2025 supported a broad range of experimental awards encompassing materials science, photon source and accelerator component R&D, plasma physics, and beam diagnostics and control, including studies leveraging artificial intelligence and machine learning. In 2026, three additional facilities joined BeamNetUS, further expanding the network’s reach and enhancing its already broad portfolio of research and development opportunities. This contribution provides an overview of the BeamNetUS program and highlights its recent progress, achievements, and future outlook.

BeamNetUS is funded by the U.S. DOE ARDAP Program under contract numbers DE-AC02-06CH11357, DE-SC0012704, DE-AC02-07CH11359, DE-AC05-06OR23177, DE-AC02-05CH11231, and DE-AC02-76SF00515.

Speaker: Wei Liu (Lawrence Berkeley National Laboratory)

23 Commissioning of a Heterodyne Near Field Speckles Beamline for Beam Size Measurements at ALBA

Electron beam size measurements using the Heterodyne Near Field Speckles (HNFS) technique were successfully tested at the ALBA beamline "NCD-SWEET". Inside the FCC collaboration, a dedicated setup was installed at ALBA Front End 21 (FE21), including a high energy (~23keV) and large bandwidth (~1.5%) multilayer monochromator to optimize the speckle pattern.
An x-ray pinhole camera is installed at the ALBA FE21, which is currently in operation using the synchrotron light from a bending magnet. Both measurement techniques (pinhole and HNFS) can operate alternately to measure the electron beam size from the same source point, allowing for direct comparison between the two methods.
This paper presents the steps taken to install the dedicated HNFS instrumentation, along with initial measurements.

Speakers: Laura Torino (ALBA Synchrotron (Spain)), Ubaldo Iriso (ALBA Synchrotron (Spain))

24 Compact multi-camera transverse and longitudinal beam diagnostics for 2 MeV proton commissioning at FRANZ

The Frankfurt Neutron Source (FRANZ) at the Institute of Applied Physics (IAP), Goethe University Frankfurt, is currently preparing for high-intensity proton beam operation up to 2 MeV. To support reliable transverse and longitudinal beam characterization downstream of the coupled RFQ–IH-DTL structure, a compact and versatile beam diagnostics section has been developed. For transverse profile monitoring, the setup combines an interceptive Chromium-doped Alumina scintillation screen with a non-invasive four-camera imaging system observing Beam Induced Fluorescence (BIF) in residual gas from two orthogonal projections. The optical readout utilizes single-board CMOS cameras, enabling automated background subtraction, 1D profile extraction, and 2D beam distribution analysis. Longitudinal parameters and beam energy are determined via Time-of-Flight (ToF) using two capacitive phase probes read out by dedicated gain and phase detectors. This contribution presents the instrumentation design, hardware selection criteria, sensor radiation tolerance considerations, and initial multi-angle profile measurements obtained during high-current proton beam operation.

Speaker: Leonie Bauer (Goethe University Frankfurt)

25 Construction status of beam instrumentation and diagnostics for SPring-8-II

We are constructing the beam diagnostic system for SPring-8-II, a low-emittance upgrade of the SPring-8 synchrotron radiation facility. To achieve higher brilliance and coherence, SPring-8-II requires stringent beam stability, necessitating high-precision monitoring of parameters such as the beam orbit, stored current, beam size, and betatron tune. Transverse and longitudinal bunch-by-bunch feedback (BBF) systems are also necessary to suppress collective beam instabilities. Furthermore, a vertical beam shaker and several scrapers are required to stretch the beam size and safely dump the beam without damaging vacuum components. The vertical shaker is also utilized for cleaning satellite electrons in nominally empty buckets. The beam orbit is monitored using 340 button-type BPMs with MTCA.4-based readout electronics, which provide sub-μm resolution at a 10 kHz sampling rate. The beam current is precisely measured by two DCCTs, and the beam size is measured by an X-ray pinhole camera with a few-μm resolution. The transverse BBF system consists of stripline pickups, RFSoC-based feedback processors, and stripline kickers powered by wideband amplifiers, achieving a damping time shorter than 0.1 ms. It also features an integrated betatron tune measurement function, and an energy kicker is prepared for the longitudinal BBF. In this presentation, we will report on the design, performance, and construction status of these beam instrumentation and diagnostic devices for SPring-8-II.

Speaker: Hirokazu Maesaka (RIKEN SPring-8 Center, Japan Synchrotron Radiation Research Institute)

26 Correction of RF shield–induced acceptance effects in a hybrid pixel beam gas ionization monitor in the CERN SPS

A Beam Gas Ionization (BGI) profile monitor has been installed in the CERN Super Proton Synchrotron (SPS) incorporating a newly designed perforated RF shield to suppress wakefield effects induced by high-frequency multibunch beams found in the SPS. While the shield effectively protects the detector from EMI effects, its aperture pattern introduces a spatial masking of the collected ionization electrons. We present a reconstruction methodology that accounts for this geometrical acceptance modulation and restores unbiased transverse beam profiles. Beam size and emittance measurements obtained with the corrected system show agreement with Wire Scanner measurements across operational beam conditions. In addition, an in situ time-walk calibration was performed using single-bunch beams to allow bunch-by-bunch profiles. These results mark a first step towards full commissioning of the two SPS BGIs which is expected to happen late 2026.

Speaker: Lukas Golino (European Organization for Nuclear Research)

27 Deployment of a new current measurement module for beam loss monitors of HIPA facility in PSI

A new current measurement module, SoM-CAM, is being deployed to replace CAMAC-based systems that have been in operation for more than 30 years in most of HIPA instrumentation electronics. Multiple tests have been performed to assess the readiness and reliability of the new module, with particular emphasis on safety-critical applications such as beam loss monitors. The enhanced capabilities of SoM-CAM enable detailed recording and analysis of the time structure of beam losses associated with interlock events. The paper presents the validation results and outlines the planned timeline for the complete replacement of CAMAC systems.

Speaker: Mariusz Sapinski (Paul Scherrer Institute)

28 Design and validation of a non-destructive real-time beam profile monitor for white photon beams

As the power density of photon beams increases in low emittance storage rings, robust and non-destructive diagnostic tools are required to replace conventional invasive monitors. Although existing Ionization Profile Monitors have demonstrated sufficient resolution for position measurement, the spatial resolution required for accurate profile reconstruction has rarely been analyzed in relation to electromagnetic field design. This presentation shows the development of a White Beam Profile Monitor capable of precise photon beam profile measurement. We utilized an electrode geometry to maximize the readout area. A key feature of our approach is the quantitative analysis of the Point Spread Function, achieved by numerically calculating the motion of ions generated during ionization. Verification tests performed at the PLS-II beamline confirmed that the measured profiles are consistent with simulation results, thereby validating our resolution analysis and demonstrating the reliable performance of the WBPM.

Speaker: Woojin Song (Pohang Accelerator Laboratory)

29 Design considerations for EIC synchrotron radiation monitors

The Electron-Ion Collider is being built at Brookhaven National Laboratory. High resolution imaging systems are required to provide robust measurements of beam emittance and energy spread. Two pinhole cameras will be installed on the electron storage ring. Radiation will be extracted from the high and low dispersion regions. One of the beamlines will be used for the visible light diagnostics as well. The synchrotron radiation will be extracted though a diamond window separating high vacuum region from low vacuum beamline. The window is protected from high power synchrotron radiation with a filter made of pyroelectric graphite. In this paper we provide resolution analyses, heat load calculations, and optimization of the pinhole cameras including beamline design.

Speaker: Igor Pinayev (Brookhaven National Laboratory)

30 Design of a Vis–UV diagnostic beamline for transverse beam size measurement at SPS-II

A visible–ultraviolet (Vis–UV) diagnostic beamline is being developed for Siam Photon Source II (SPS-II) to enable precise transverse electron beam size measurements. The vertical (π) polarization technique using the dipole radiation has been selected to enable vertical beam size measurements below 10 µm. Given the limited space available in the double-triple bend achromat (DTBA) lattice, a removable first mirror has been designed for installation inside the dipole vacuum chamber. This introduces significant engineering challenges in extracting diagnostic photons while managing the substantial thermal load from the dipole radiation fan, without inducing flow-related vibration or optical surface deformation. This paper presents the conceptual design of the first mirror system, associated thermal and mechanical considerations, and the optical layout of the Vis–UV diagnostic beamline. Detailed beamline modeling and synchrotron radiation calculations performed using Synchrotron Radiation Workshop (SRW) are also presented to evaluate beam transport and diagnostic performance.

Speaker: Porntip Sudmuang (Synchrotron Light Research Institute)

31 Design of an emittance meter for the CSNS MEBT

The CSNS will refurbish the ion source, RFQ and MEBT sections this year, among which a new compact emittance meter at the MEBT is required. This emittance meter will be intergated with beam scraptor and wire scanner owing to the compact design of the CSNS MEBT section. This emittance meter consists slit in blades made of tungsten, and four SEM wires to visualize the beamlet profile. In this paper, we report the optimization of the slit structure, beamlet drift distance and wire diameters in the presence of realistic conditions. Moreover, the selection of material and accuracy of the transverse phase-space distribution measurement are also outlined.

Speaker: Renjun Yang (Institute of High Energy Physics)

32 Design of Elettra 2.0 x-ray diagnostics beamline

This paper reports on the design of the x-ray diagnostic beamline (XDBL1) dedicated to the emittance measurement of Elettra 2.0 storage ring. Elettra 2.0 is the Italian 4th generation diffraction limited storage ring (DLSR) light source currently under construction at the Elettra - Sincrotrone Trieste laboratory. It is designed to operate at 2.4 GeV, 400 mA and beam emittance of 212 pmrad. To characterize and monitor the beam size, the XDBL1 is foreseen to provide an online beam emittance measurement suitable for slow beam feedbacks. The XDBL1 is based on the x-ray pinhole camera (XPC) design for robust operation within the operational Elettra 2.0 parameters. The paper describes the beamline layout, the design constraints and the simulations results performed using OrAnge SYnchrotron Suite (OASYS). XOP under python3+orange3 sofwtare (XOPPY) was used to evaluate flux density and beamline transmission at key positions. Synchrotron Radiation Workshop (SRW) was used to calculate the monochromatic and polychromatic PSF for selected possible configurations. A description of the pinhole design and detections system are also provided. Provisions for future upgrades for machine configurations with more demanding resolution are also discussed.

Speaker: Marco Veronese (Elettra-Sincrotrone Trieste S.C.p.A.)

33 Design study of a Cherenkov diffraction radiation beam profile monitor for the PLS-II injector beam transport line

Cherenkov diffraction radiation (ChDR) has been widely studied for non-invasive transverse diagnostics of relativistic charged particle beams. In this work, we present a design study of a ChDR based beam profile monitor for the beam transport line of the Pohang Light Source-II (PLS-II) injector at Pohang Accelerator Laboratory (PAL). In the beam transport line, especially at the injector section, various mechanical structures must be placed in a confined space, so simple instruments are required. Furthermore, conventional profile monitors, such as YAG screens and wire scanners, are interceptive, which limits their use for online profile measurements during tuning. A ChDR based beam profile monitor is considered a compact, non-invasive option for transverse beam diagnostics. Since the ChDR intensity decreases exponentially with increasing impact parameter between the beam and the dielectric radiator, we investigate the diagnostic response for a 3~GeV electron beam. Based on calculation results, we evaluate the measurable dynamic range of the proposed ChDR beam profile monitor. These results support the feasibility of a ChDR diagnostic system for transverse beam profile measurements for the PLS-II injector beam transport line.

Speaker: Moses Chung (Pohang University of Science and Technology)

34 Development of a novel high angular resolution tracking system at the CERN SPS North Area test beam

The BIPXL telescope is a high-precision tracking system developed at CERN for the characterization of bent silicon crystals in secondary particle beams. The system measures channeling efficiency, track deflection and crystal alignment. It consists of two 10 m tracking arms equipped with up to six hybrid pixel detector (HPD) planes, scintillator-photomultiplier tube (PMT) trigger stations, adjustable detector stages, and a high-precision multi-axis goniometer for crystal alignment. Its configurable geometry accommodates different test scenarios depending on tracking performance requirements. The current prototype setup consists of Timepix3 HPDs and achieves a spatial and angular resolution down to 20 um and 20 urad, respectively. Still, further improvements in effective detection area and material budget are required to meet tracking requirements. The HPDs are integrated using a radiation hard readout architecture developed within the CERN Beam Instrumentation group. Dedicated solutions for motion control, system coordination and online reconstruction enabled development and deployment of the full system in less than a year and stable multi-day test-beam campaigns since. First measurements demonstrate reliable operation and confirm the expected performance. The presented prototype system represents a first step towards a low-material-budget high angular resolution telescope, with future developments based on hybrid pixel detectors using the newest-generation Timepix ASIC.

Speaker: Justus Braach (European Organization for Nuclear Research)

35 Development of an optically diagnosed ECR H⁺ ion source with additively manufactured ion optics

An electron cyclotron resonance microwave H+ ion source featuring low normalized beam emittance (<1 π mm mrad) and up to 20mA at 35keV beam energy has been developed at the HUN-REN Centre for Energy Research in Budapest, Hungary. The beam can be operated in a continuous or pulsed way that is adjustable in duration (0.1-10ms) and frequency (0.01-40Hz) at 35keV. A novel optical diagnostic system has been implemented, providing high-voltage insulation (up to 40 kV) between the plasma chamber and the camera. Viewports consisting of 10 mm diameter holes sealed with glass windows are implemented on both the plasma chamber and the extraction chamber. These are angled in a way to observe the extraction aperture of the proton beam from both the plasma chamber and the ion optics region. The insulation of an endoscopic camera with an outer diameter of 4mm is accomplished with a glass tube and a glued flat lens. The experimental validation of the high-voltage insulation properties of the adhesive and the different thicknesses of the glass has been conducted. Moreover, the ion optics design has been optimized for gas flow and precise electrode assembly by refining parts using additive manufacturing. This study describes a unique optical diagnostic design to observe and evaluate the H+ plasma and the extracted ion beam as a function of microwave power and hydrogen flow rate, along with improvements to the ion optics design for optimized gas conductance and simplified electrode assembly.

Speaker: Domonkos Czeman (HUN-REN Centre for Energy Research)

36 Development of In-Air X-ray Detector for vertical beam size measurement at SESAME

An In-Air X-ray Detector (IAXD) was designed and installed at the SESAME storage ring (SR) dipole exit in order to use the photon X-ray part coming out of the dipole photon absorber. The IAXD uses a scintillator placed directly downstream the absorber, converting transmitted X-rays into visible light. Two types of scintillation screens, CdWO₄ and GOS:Tb, were used and compared over a range of exposure times up to 8 seconds. Given the vertical divergence of 86 keV photons and the distance between the source point and the scintillator, it is possible to accurately calculate the vertical beam size at the source point. This paper presents the measurement results obtained with the IAXD and evaluates its feasibility as a complementary diagnostic tool in the 2.5 GeV storage ring.

Speaker: Hussein Al-Mohammad (Synchrotron-Light for Experimental Science and Applications in the Middle East)

37 Electron detection system for the LANSCE laser wire scanner

At present the Los Alamos Neutron Science Center (LANSCE) beam line has transverse beam shape diagnostics consisting only of physical wire scanners and emittance stations. Knowledge of the transverse beam shape is critical to tuning the beam through the accelerator and for beam monitoring during regular operations. However, the existing diagnostics can only be used at low beam power; at full power they produce too much radiation spill. Recently, we installed and collected initial data from a laser wire scanner installed in the low energy beam transport (LEBT) portion of the accelerator. This diagnostic prototype uses a high energy 1064 nm laser to strip electrons of a portion of the H- bunch and detect the liberated electrons in a Faraday cup. This work presents an overview of the prototype and details of electron detector.

Speakers: Heather Andrews (Los Alamos National Laboratory), Martin Kay (Los Alamos National Laboratory)

38 Feedthrough developments for the charged particle accelerators

Feedthroughs are widely used for different charged-particle accelerators. Those feedthroughs are used to transfer the RF signals, the DC or AC low level signal, the high-current, and the high-power. In order to complete these purposes, different feedthroughs have been developed and have already been used for different accelerators in China. This report introduces the development of the different feedthroughs by ANDSUN and Nanjing University.

Speaker: Sun An (Nanjing University)

39 High-speed turn by turn and bunch by bunch transverse beam size measurement using a spatial interferometer and photomultiplier tube

For next generation storage rings and free electron lasers, which demand ultra low emittance and exceptional beam stability, precise and fast transverse beam size monitoring has become increasingly critical. Conventional imaging based methods are often limited by camera frame rates and photon flux, making it difficult to achieve bunch by bunch resolution under low photon conditions. To address this challenge, we have developed a novel measurement system that combines a spatial interferometer with a high speed photomultiplier tube (PMT). The interferometric setup converts spatial coherence information into temporal signals, while the PMT provides sub nanosecond response, enabling turn by turn and even bunch by bunch beam profile acquisition. Through dedicated beam experiments and advanced algorithmic optimization, we simultaneously improve both the data refresh rate and spatial resolution. The system has been tested on a synchrotron light source, demonstrating real time capture of fast beam size variations that are inaccessible with conventional cameras. This approach not only meets the stringent requirements for online monitoring and fast feedback in modern accelerator facilities, but also lays a solid foundation for developing active beam size control techniques. The results show that the proposed method operates reliably at low photon counts, offering a promising pathway toward high speed, high precision beam diagnostics for future light sources.

Speaker: Yimei Zhou (Shanghai Advanced Research Institute)

40 Improving ion profile monitor measurements with simulation and ML

Ion profile monitors (IPMs) are important non-destructive diagnostics for transverse profile measurement, but space-charge forces and other effects can distort the ion distribution, biasing inferred beam size and emittance. We are developing a simulation- and ML–based framework to improve the accuracy and reliability of IPM measurements in the Alternating Gradient Synchrotron (AGS) at Brookhaven National Lab. Using datasets generated with the Warp particle-in-cell code, we train supervised models that infer the true transverse beam size from short scans of collector voltage and simple profile features, without explicit knowledge of other bunch parameters. To improve profile robustness, we also investigate deep-learning methods for signal denoising and quality control, using autoencoder and transformer models to learn compact profile representations. These tools identify noisy or atypical measurements and reduce errors in downstream fitting. Together, they form an end-to-end AGS IPM analysis chain that removes noise, flags anomalies, and applies ML corrections for physical distortions, enabling robust emittance monitoring for current operations and future machines.

Speaker: Christopher Hall (RadiaSoft (United States))

41 Improving the double slit interferometer setup at KARA to achieve turn-resolved transversal beam size measurements

At the Karlsruhe Research Accelerator (KARA), electron beams of up to 200 mA are stored with an energy of 2.5 GeV, while injection is performed at 500 MeV.
At a five degree port of a bending magnet, a double slit Interferometer setup is used to measure the transversal beam size. In oder to digitize the interferogram in the visible spectrum, previously a CMOS camera has been used, which yields averages of the beam size over a few milli seconds. Since the beam size information in the interferogram is contained in one dimension, a fast line camera can be used instead. KALYPSO is a KIT-developed line camera which can be triggered at every revolution of KARA.
In this contribution we report on the necessary mechanical and optical improvements to implement the KALYPSO readout path and show the system is sensitive enough to get beam size readings for single-bunch operation.

Speaker: Marvin Noll (Karlsruhe Institute of Technology)

42 Ionization profile monitors for the IOTA storage ring at Fermilab

Ionization profile monitors (IPM) are used in many accelerator laboratories around the world for non-destructive profile measurements of high-energy particle beams. They have been used in nearly all the synchrotrons built at Fermilab and are presently used in the Main Injector (MI), Recycler (RR), and Booster. This paper will present the current status of the design of a new pair of IPMs to be installed in the Integrable Optics Test Accelerator (IOTA), an experimental proton storage ring with a beam energy of 2.5 MeV. The design incorporates aspects of several IPMs previously or currently used at FNAL. Similar to the Booster IPM, ions are collected rather than electrons, thus requiring no external magnetic field. To increase the signal, each IPM uses two microchannel plates in the chevron configuration as is done in the MI/RR IPMs, and due to the ring's ultrahigh vacuum conditions, the local vacuum pressure is increased with a calibrated leak, akin to the former Tevatron IPMs, to increase the ionization yield per bunch. Data acquisition includes upgraded preamplifiers and leveraging of the digitizer design of the beam position monitor system already in use at IOTA. In addition to the mechanical and electronic designs, simulation results of the effects of the electric fields and injected gas on the circulating beam will also be presented.

Speaker: Randy Thurman-Keup (Fermi National Accelerator Laboratory)

43 Laser parameterisation for an upgraded LINAC4 laserwire diagnostic at CERN

The laserwire is a non-destructive, commensal beam profile monitor and a highly viable, minimally invasive diagnostic already implemented at several accelerator facilities, with advantages for future collider applications. Here, a short-pulse, laserwire-based method is proposed to upgrade the laser system for the 160 MeV negative hydrogen ion beam of the LINAC4 at CERN. The improved system can perform combined transverse and temporal profile measurements, as well as access longitudinal parameters through temporal asynchronisation of the laser pulses with the beam bunches. Initial studies have been carried out by simulating the interaction of the laserwire with Gaussian-distributed 160 MeV negative hydrogen ion beams across a range of short-pulse durations and energies using Beam Delivery Simulation (BDSIM) software. These simulations have been used to parameterise the requirements of the upgraded laser system.

Speaker: Tiago Fernandes de Nóbrega (Royal Holloway University of London)

44 LUCID – Luminescence-based gas Curtain Imaging Diagnostics for beam profile analysis

An ECR microwave H+ source has been built at the HUN-REN EK-CER that targets medium current (20mA) and 35 keV beam energy in continuous or pulsed mode (0.1-10ms @ 0.01-40Hz) and low normalized beam emittance (< 1 π mm.mrad).
A supersonic gas jet-based diagnostic system called LUCID is being developed at EK-CER that can provide a non-invasive beam profile measurement * and allows a novel way for emittance evaluation with an additional mesh to create beamlets. The diagnostic uses a nozzle and skimmers to form a thin (~2 mm) and dense (1017 1/m3) gas curtain of an interaction cross section of ~10x10mm2 inclined at 45° to the beam axis. A CMOS camera is installed to record the yielded photons (~s exposure time, approximately 108 photon/s) from the interaction of the proton beam and gas curtain. It is crucial to use a gas that has a high collisional cross section (e.g. Ar, N or Ne) ** and is easy to distinguish from the residual gas (N) excitation to ensure noiseless detection. This can be achieved by using wavelength filters before the CMOS camera.
This study describes the measurement results of LUCID including gas selection, jet formation (nozzle and skimmer design, curtain thickness and density) and vacuum system configuration. Finally, measurement results are compared with simulations.

Speaker: András Zsákai (HUN-REN Centre for Energy Research)

45 Novel optical methods for multipacting characterization during RF conditioning

Multipacting, driven by resonant secondary electron emission, is a critical phenomenon during the conditioning of RF cavities. To investigate and characterize this effect, novel and low-cost optical diagnostic methods utilizing single-board CMOS cameras (Raspberry Pi cameras) have been developed at IAP Frankfurt. Building on their successful application in ion beam characterization, these compact cameras were installed both inside and outside the vacuum system of the FRANZ (Frankfurt Neutron Source) RF cavities.
The conditioning campaign was conducted in two distinct phases: initially, the RFQ (Radio-Frequency Quadrupole) and the IH-DTL (Interdigital H-mode Drift-Tube-Linac) were conditioned as standalone structures. Subsequently, both cavities were coupled and conditioned together. Throughout both phases, the camera setup enabled the in-situ optical detection of multipacting and other luminescence effects.
The experimental observations are corroborated by simulations, which confirm the onset of multipacting at specific RF power levels. Furthermore, complementary spectrometer measurements provide a detailed characterization of the observed processes.

Speaker: Leonie Bauer (Goethe University Frankfurt)

46 Optimization of the ion trap for secondary electron suppression in the CSNS RCS IPM

Non-destructive beam profile monitoring is critical for high-intensity proton accelerators like the CSNS Rapid Cycling Synchrotron (RCS). While the Ionization Profile Monitor (IPM) typically reconstructs beam profiles by collecting ionization electrons from residual gas, a key challenge arises from positive ions drifting toward the field cage. Their impacts generate secondary electrons that propagate back to the detector, causing significant beam profile distortion. To mitigate this, an ion trap with a specifically designed slit opening was implemented. This structure selectively allows positive ions to pass through the slit and be confined on the rear side, while effectively suppressing secondary electrons from reaching the sensor. A comprehensive simulation study was performed to optimize the ion trap geometry and performance for the IPM. This paper presents the optimization process and results for the ion trap implemented in the CSNS RCS IPM.

Speakers: Renjun Yang (Institute of High Energy Physics), Yuliang Xiao (Institute of High Energy Physics)

47 PIP-II beam instrumentation for beam commissioning

As part of the new Proton Improvement Plan (PIP-II), Fermilab is undertaking the development of a new 800 MeV, 2 mA H- superconducting RF linac to replace its present normal conducting 400 MeV linac. The PIP-II linac consists of a series of superconducting RF cryomodules from 2.1 MeV to 800 MeV, with instrumentation warm units between cryomodules. Commissioning of this new accelerator will occur in stages starting in 2027. This paper will describe the staged beam commissioning plan, as well as the permanent and temporary beam instrumentation to be used.

Speaker: Victor Scarpine (Fermi National Accelerator Laboratory)

48 Proton beam irradiation and transport system for the RFT-30 cyclotron

Four beam lines are currently in operation at the RFT-30 cyclotron. As the demand for various radioisotopes continues to grow, we focused on proton irradiation stability to improve the production yield. The beam behavior along the transport line was investigated so that the irradiation area could be matched to the geometry of the target. For this purpose, the beam trajectory was first aligned with a steering magnet, and the size of the irradiated spot was then tuned through a triplet quadrupole. A sine-wave driven wobbler magnet was subsequently introduced to sweep the beam along a circular waveform, thereby flattening the beam profile across the target surface. The resulting proton distribution was recorded on a Gafchromic film under a low-current beam, and an irradiation area was achieved at an optimal wobbler current.

Speakers: Jongchul Lee (Korea Atomic Energy Research Institute), Donghyun Kwak (Korea Atomic Energy Research Institute)

49 Pulsed-beam capability for the D-Pace ES-4 emittance scanner

The D-Pace ES-4 is an Allison-type emittance scanner used for transverse phase-space measurements in low-energy beam transport systems. Standard picoammeter-based acquisition is suitable for DC beam but is not well suited to short pulsed beams. A pulsed measurement system has therefore been developed around a custom charge integrator and synchronized controller architecture. The charge integrator measures collector charge within a defined gate referenced to an external beam trigger. This permits phase-space measurements at low duty cycle without requiring continuous beam current. The development included a low-noise charge-integrator front end, configurable integration and reset timing, trigger input circuitry, synchronization with scanner motion and electrode bias control, and acquisition software. The system was designed to accommodate variation in pulse width, repetition rate, beam current, and trigger timing. Initial tests demonstrate repeatable charge measurements synchronized to the beam pulse and support for pulsed emittance scans. The upgrade extends the ES-4 scanner platform to pulsed ion-source and low-energy beam applications.

Speaker: Zack Watkins (D-Pace Inc.)

50 Python for beam spot analysis

The Canadian Light Source (CLS) is a 3rd generation synchrotron commissioned in 2005. In the years since, technology has advanced dramatically, facilitating new options for instrumentation tools. The CLS has begun replacing expensive commercial BeamGage cameras running proprietary software with inexpensive highly capable Machine Vision (MV) cameras. This paper describes the use of open source Python packages (numpy, scipy, etc) along with inexpensive MV cameras to measure beam parameters such as major and minor axis, elipticity, and orientation, based on raw beam images and Guassian approximations fitted to the data. The results are compared to those generated by the BeamGage system.

Speaker: Michael Bree (Canadian Light Source (Canada))

51 Radiation tolerance testing of the cooled CMOS camera for beam profile monitoring

Scintillating screens equipped with optical cameras are widely used in accelerator facilities for transverse beam profile monitoring, as this method is simple and precise compared to other beam diagnostics. However, the image sensor is sensitive to secondary radiation induced by the interaction between the particle beam and the scintillation screen. Radiation damage degrades the performance of image sensors by increasing hot and dead pixels, which poses a major hurdle for camera-based beam profile monitoring. To address this issue, we developed a radiation-tolerant beam viewer using a cooled CMOS camera. In this contribution, we present the radiation tolerance test results of the cooled CMOS camera and demonstrate the feasibility of this new radiation-tolerant beam viewer system.

Speaker: Sang-Pil Yun (Korea Multi-purpose Accelerator Complex)

52 Re-developing the extract beam loss trip system for the ISIS synchrotron

The ISIS Neutron and Muon Source at the Rutherford Appleton Laboratory, UK, uses a rapid cycling synchrotron to accelerate a beam of protons from 70 MeV to 800 MeV before delivering the beam to two spallation targets. Within the ring of the ISIS synchrotron, beam losses tend to be higher near the kicker magnets and the start of proton extraction beamlines. The increased levels of beam loss induce more radioactivity in surrounding structures of the synchrotron, which has safety implications for personnel performing maintenance work in the vicinity. Thus, it is crucial to monitor loss levels in the beam loss monitors (BLMs) local to the extraction area. A separate “trip”, i.e. a signal to stop the beam, is needed for that part of the ring. The Extract Trip Unit generates trips on the condition that losses are too high at extraction in the ring, in both a spatial (i.e. the specific ionisation chamber BLM local to the area of extraction) and temporal sense (part of the ISIS acceleration cycle during which the beam is extracted). The previous version of the Extract Trip Unit was inoperative, with obsolete components. As part of the ISIS Diagnostics obsolescence initiative, the purpose of this project was to redesign the obsolete unit and reintegrate a new Extract Trip Unit into the system. This work illustrates the process of modernising and re-deploying the Extract Trip Unit, including the updated design considerations and the step-by-step breakdown of its functions.

Speaker: Anna Sofija Salosteja (ISIS Neutron and Muon Source)

53 Revealing beam loss mechanisms through joint bunch-by-bunch measurement of beam loss and three-dimensional position

To monitor and analyze the beam loss characteristics during the operation of the Hefei Light Source II (HLS-II), a synchronous bunch-by-bunch measurement system for beam loss and three-dimensional beam position has been developed based on a scintillator detector, a stripline beam position monitor, a high-speed oscilloscope, and the HOTCAP technique. However, the scintillator detector is limited by its resolving time and cannot provide effective bunch-by-bunch beam loss discrimination in high-fill-density storage rings, especially under high loss-rate conditions. To overcome this limitation, a double-exponential pulse trapezoidal shaping algorithm is introduced to resolve piled-up pulses and correct their amplitudes. This system is used to monitor beam losses during both the decay cycle and injection transient process of the HLS-II. During injection transients, a previously unreported evolution pattern was observed, in which beam loss propagates forward from the injected bunch. This phenomenon can be reasonably interpreted in terms of the unbound longitudinal phase-space evolution of particles outside the stable region, together with the longitudinal oscillations of the stored bunches.

Speaker: Xinru Gao (University of Science and Technology of China)

54 Simulation analysis of space charge effects on IPM-measured transverse beam profiles

The China Spallation Neutron Source (CSNS) is a high-power proton accelerator facility for neutron scattering research. The Rapid Cycling Synchrotron (RCS) is equipped with an Ionization Profile Monitor (IPM) for non-destructive measurement of the transverse beam profile. Following the CSNS-II upgrade, the injection beam current will increase to 40 mA, making space-charge-induced distortion a critical issue for accurate IPM measurements. In this work, numerical simulations were performed using an IPM simulation code to investigate the IPM response during the RCS painting injection process. The deviations between the reconstructed IPM profiles and the reference beam distributions were quantitatively evaluated under various beam conditions for both ion and electron collection modes. The simulation results provide a quantitative assessment of space-charge-induced measurement errors and demonstrate the performance of the two collection modes under high-intensity beam conditions, providing guidance for the interpretation of IPM measurements and the optimization of IPM operation in the CSNS-II RCS.

Speaker: Mengyu Liu (Chinese Academy of Sciences)

55 Status of the high luminosity LHC beam instrumentation

This contribution presents an overview of the new beam instrumentation being developed and produced for the ongoing LHC luminosity upgrade. There are 7 different packages planned for LHC operations from 2030, ranging from large distributed systems for beam position and beam loss to new dedicated instruments for transverse profile, beam halo, luminosity and beam crabbing monitoring. The contribution will summarise results from the latest tests with beam, decisions taken for instrument designs and the status of production and integration into the LHC.

Speaker: Raymond Veness (European Organization for Nuclear Research)

56 SWAT parameter optimization of the magnetic center measurement of Scorpius Accelerator Region solenoids

The precision of the Stretched Wire Alignment Technique for determining the magnetic center of the Scorpius Accelerator Cell solenoids in reference to their geometrical axes is critically impacted by the selection of various experimental parameters. This work presents an experimental optimization of key SWAT parameters to minimize measurement errors using the Entry Transport Region-prototype solenoid to emulate the solenoid characteristics of Scorpius Accelerator. On a dedicated test stand, we varied the solenoid current, copper test wire gauge, stretched wire tension weight, and the scanning ranges. We performed 80 experiments. In each scan the wire deflections before and after the current pulse were measured by two precision micrometers at 36 different locations set by the scanning pattern. For each set of parameters, the experiment was repeated four times. The result was determined as the average of these four experiments, while the standard deviation was used as figure of merit for the overall system precision. The optimization revealed a clear optimal operating point. Variation of the scanning pattern amplitude was found to have a minimal influence on the results. By implementing these optimized parameters, both the measurement error and result reproducibility were improved. Our findings provide a set of parameters to find the magnetic center with necessary precision, which is critical for meeting the stringent alignment tolerances required for the Scorpius accelerator.

Speaker: Mario Valles Montenegro (Nevada National Security Site)

57 Synchrotron light interferometry for beam energy spread measurement at JLab

High-precision mass spectroscopy of $\Lambda$-hypernuclei is currently underway at the Thomas Jefferson National Accelerator Facility (JLab). To achieve the world's highest mass resolution of $500\text{ keV}$ (FWHM), minimizing the energy spread of the $2.2\text{ GeV}$ incident electron beam is crucial. As a method for simultaneous and continuous monitoring of this energy spread, we have developed a "synchrotron light interferometry" system. In this method, synchrotron radiation emitted from a bending magnet is observed using double-slit interferometry. The beam size, which is approximately $200\ \mu\text{m}$, can be estimated from the visibility of the interference fringes. Because this measurement is performed in a high-dispersion region of the beamline, the beam size is primarily determined by the dispersion and momentum spread.
Continuous measurements have commenced this summer, and we plan to calibrate the beam size measurements in conjunction with the wire-scan method prior to the hypernuclear experiment scheduled for 2029. In this presentation, we report on the current status of preparations, focusing on the optimization of the experimental setup, including the beam optics and the optical system for synchrotron radiation observation. Furthermore, we discuss future prospects for the system, including plans to develop an automated gang phase control utilizing the SLI to minimize energy spread.

Speaker: Kotaro Nishi (The University of Tokyo)

58 Test laboratory setup for synchrotron RF systems based on LLRF, resonant cavity, and RF transmitter

This contribution describes the preparation and integration of a test RF laboratory dedicated to synchrotron accelerator systems. The laboratory supports testing and validation of an RF chain composed of a Low-Level RF (LLRF) system, an RF resonant cavity, and an RF transmitter supplying power to the cavity. While the synchrotron is already in operation, the laboratory is being developed as an independent environment for component-level tests, system integration, and configuration studies prior to deployment in the machine. The work focuses on hardware integration, network infrastructure, and configuration aspects relevant for stable RF operation. The hardware setup includes the LLRF system, the resonant cavity with tuning and diagnostic elements, and the RF transmitter chain ensuring controlled RF power delivery. Particular attention is given to subsystem interfaces, RF signal routing, and protection mechanisms required for safe laboratory operation. The control software is based on the TANGO framework and provides essential device control, configuration, and monitoring capabilities. As part of the laboratory infrastructure, a dedicated VLAN has been established for the RF system, hosting the TANGO database and enabling isolated and structured configuration of control services. The described setup provides a flexible test environment supporting further development and validation of synchrotron RF systems.

Speaker: Michał Fałowski (Jagiellonian University, SOLARIS National Synchrotron Radiation Centre)

59 Tests of a new Oscillating Arm Wire Scanner for HIPA at PSI

The Oscillating Arm Wire Monitor (OAWM) is a new type of wire scanner designed to operate at maximum speeds exceeding 4 m/s, which are required to perform scans of high-intensity beams. This paper summarizes the comprehensive tests and measurements carried out on the OAWM, focusing on both its operational endurance and its underlying mechanical dynamics. We report on extensive endurance tests, comprising thousands of scans, to validate long-term system reliability in high-intensity beam environments. In addition, we analyze the vibrations of the fork at various speeds and investigate the corresponding damping behaviour. Fast operation tests were successfully conducted in a primary beamline (e.g., the 870 keV line) to verify that signal quality is maintained under realistic operating conditions. The results demonstrate that reduced inertia and optimized gear ratios enable faster, more stable, and highly reliable beam diagnostics.

Speaker: Mariusz Sapinski (Paul Scherrer Institute)

60 Update of the CERN beam instrumentation R&D roadmap to complete the LHC era and prepare next-generation accelerators

The completion of LHC Run~3 marks a natural milestone to assess the
state of the art in beam diagnostics across the CERN accelerator
complex and to define the instrumentation developments ahead. This
contribution presents an updated R\&D roadmap for the CERN Beam
Instrumentation group, built from a concise review of the current
diagnostics portfolio, known operational limitations requiring upgrade
or redesign, and needs collected from future accelerator
studies. Key R\&D lines include next-generation electromagnetic
pick-ups and monitors, non-invasive transverse and longitudinal beam
profiling, and novel interceptive diagnostics based on low-density
materials. A challenge shared by many of these developments is the need
for detector and readout technologies that perform reliably in
radiation environments, as illustrated by the requirements on beam
imaging systems, driving work on radiation-tolerant detectors,
front-end architectures, and high-dynamic-range, fast DAQ systems. The
roadmap also considers the growing role of automation, AI-assisted
analysis and ML techniques,
and is positioned against the CERN timeline for full exploitation of
the accelerator complex and for the feasibility of next-generation
facilities such as the Future Circular Collider (FCC).

Speaker: Federico Roncarolo (European Organization for Nuclear Research)

61 Using a triangle pinhole for beam imaging

The pinhole cameras are used for the electron beam diagnostics with X-ray imaging. We propose to utilize the triangle shaped pinhole formed with three blades. Such design simplifies the aperture control with motion of a single blade. We present the simulations results as well as tests of a prototype with visible light.

Speaker: Igor Pinayev (Brookhaven National Laboratory)

62 Visible light beam profiling under high current operations at SuperKEKB

We report on the latest measurement results from the visible light synchrotron radiation monitor　(SRM) during high　current operation at SuperKEKB. Beam measurements covering both steady state conditions and rapid transient phenomena—specifically "final-turn" measurements—revealed an increase in vertical beam size immediately before the beam was aborted during sudden beam loss (SBL) events. Subsequent measurements in the HER and LER rings identified differences in the phenomena observed between the two rings. While the optical system's high dynamic range enabled precise measurement of beam halo profiles over a wide range, we present measurement results for the LER following the implementation of SBL countermeasures and compare them with before countermeasure data.

Speaker: Hitomi Ikeda (High Energy Accelerator Research Organization)

Tuesday 1 September

MC06: Feedback Systems and Beam Stability

Convener: Yongbin Leng (University of Science and Technology of China)

63 Experimental demonstration of emittance coupling control via an AC skew quadrupole driven at the difference resonance (Qx-Qy)

Short Touschek lifetime is a critical aspect of low emittance electron storage rings. To ensure an acceptable lifetime, many new machine designs rely on some kind of blowup of the vertical emittance. In view of the upgrade of the ALBA storage ring, it was decided to explore the possibility to use betatron coupling to increase the vertical emittance. To avoid the constrain of operating onto the resonant condition Qx=Qy, we use an AC skew quadrupole driven at the difference Resonance (Qx-Qy). Unlike other forms of vertical emittance blowup, this method generates a true transverse emittance sharing resulting in an increase of the vertical emittance and a reduction of the horizontal one, therefore mitigating the loss in performance due to the sole vertical emittance blowup. This presentation covers the underlying theory, the hardware implementation of the AC skew quadrupole system, and the experimental results obtained with the current ALBA beam.

Speaker: Michele Carlà (ALBA Synchrotron (Spain))

64 Distributed acoustic sensing for accelerator stability and environmental diagnostics

The stability of modern accelerator facilities depends on precise monitoring of environmental vibrations and ground motion, which can affect beam orbit, arrival time stability, and beam instrumentation. Distributed Acoustic Sensing (DAS) transforms standard optical fibers into dense arrays of strain sensors, providing high spatial and temporal resolution over tens of kilometers.
At DESY, a campus-wide DAS fiber network enables continuous monitoring of seismic and acoustic perturbations. We report on recent R&D activities demonstrating DAS as an accelerator diagnostics tool.
We demonstrate that DAS complements conventional beam instrumentation and seismometers, enabling cross-checks with beam arrival monitors and offering new opportunities to improve arrival time stability at the European XFEL.

Speaker: Markus Hoffmann (Deutsches Elektronen-Synchrotron DESY)

65 Nondestructive beam energy spread diagnostics for the development of RF phase feedback in linear accelerators

RF phase stability is important for linear accelerators, especially for high-repetition-rate free electron lasers (FELs), where phase feedback is required. Compared with direct RF field measurements, methods based on beam energy spread measurements can reflect the impact of RF perturbations on beam quality and are more suitable for feedback. Conventional screen-based destructive measurements are not applicable to high-repetition-rate operation and real-time feedback requirements. Therefore, nondestructive energy spread monitoring has been developed for RF phase feedback. A quadrupole moment measurement method based on the TM$_{220}$ mode of a rectangular RF cavity has been proposed. Using its narrowband response, high signal-to-noise ratio (SNR) measurement of the beam quadrupole moment is achieved. The monitor has been validated in beam experiments. At 350 pC, the energy spread measurement uncertainty is below $10^{-5}$, and RF phase resolution is better than 1°. Meanwhile, an eight-stripline monitor system with optimized electrode structure has also been developed for bunch-by-bunch energy spread measurements in a dispersive section. The system integrates MHz repetition-rate electronics. An online resolution evaluation method based on error propagation is proposed, enabling resolution characterization using a single monitor. Beam experiments confirm stable energy spread measurement and RF phase monitoring capability. This work provides an experimental basis for high precision RF phase feedback based on beam diagnostics.

Speaker: Qian Wang (University of Science and Technology of China)

10:20 Break

MC05: Longitudinal Diagnostics and Synchronization

Convener: Junhui Yue (Institute of High Energy Physics)

66 Longitudinal phase-space diagnostics using passive wakefield streakers at European XFEL / PSI / DESY

Longitudinal phase-space (LPS) diagnostics of high-energy electron beams are essential for the operation, optimization, and physics studies of free-electron lasers. At the European XFEL, a single-plate corrugated structure has been installed downstream of the SASE2 undulator to measure the LPS of the electron beam. When the beam passes in close proximity to the plate’s corrugations, wakefields are generated that induce a correlation between longitudinal position and transverse beam distribution. The longitudinal phase space of the beam is then analyzed on a scintillating screen monitor located in a dispersive section.
This passive wakefield streaker serves as an alternative to radio-frequency transverse deflecting structures, offering a compact, cost-effective, and operationally robust solution for post-undulator LPS diagnostics. Owing to the intrinsically nonlinear nature of wakefield-induced streaking, the measured beam images represent a nonlinearly distorted projection of the LPS, requiring dedicated reconstruction techniques.
In this contribution, we report on the operational use of a passive corrugated wakefield streaker for longitudinal phase-space measurements at the European XFEL. We discuss practical aspects of streaker operation, calibration, and resolution, and present a reconstruction method enabling reliable retrieval of the LPS under typical XFEL operating conditions.
*** SPC NOTE: Expand to include experiences at multiple institutions ***

Speaker: Sergey Tomin (Deutsches Elektronen-Synchrotron DESY)

MC06: Feedback Systems and Beam Stability

67 Real-time direct sampling bunch-by-bunch arrival time measurement on RF systems-on-chip for multibunch feedbacks

Traditional longitudinal bunch‑by‑bunch feedback systems use analog mixers to down‑convert GHz‑range RF signals to baseband, where the mixer output is approximately proportional to the bunch charge and the deviation from the nominal arrival time. We present an alternative approach that determines the beam arrival time through time‑domain processing of directly sampled BPM signals on an RFSoC. We previously demonstrated this method by processing a subset of real‑time ADC data in software on the RFSoC’s internal CPU for slow (Hz‑scale) filling‑pattern measurements and feedback. The new implementation instead processes the full ADC stream continuously in the programmable logic (PL) with low latency. A modified algorithm, optimized for PL, enables continuous arrival‑time measurements for every bunch, as required for low‑latency bunch‑by‑bunch feedback. Using suitable time‑domain techniques, even large arrival‑time variations can be measured with higher linearity, without a phase‑tuned local oscillator. Traditional systems cannot achieve this, as analog down‑conversion becomes increasingly nonlinear — and even non‑monotonic — for larger timing deviations, a common limitation in booster synchrotrons. We present measurements from the SLS 2.0 storage ring, demonstrating the feasibility of the implementation using an RFSoC with eight interleaved 4‑GS/s ADCs, achieving a 32‑GS/s effective sampling rate.

Speaker: Boris Keil (Paul Scherrer Institute)

12:00 Lunch (not included in registration)

Lunch is not provided in the registration fee. Attendees are encouraged to visit the many restaurant locations in the Village of Whislter

MC05: Longitudinal Diagnostics and Synchronization

Convener: Peter Forck (GSI Helmholtz Centre for Heavy Ion Research)

68 Femtosecond-resolution longitudinal bunch profile monitor using coherent transition radiation imaging

Ultrashort bunch length and longitudinal beam profile measurements are essential for characterizing electron beams in short-pulse accelerators, including free-electron laser facilities and novel accelerator concepts such as EuPRAXIA. A single-shot longitudinal diagnostics approach based on broadband spatial imaging of coherent transition radiation (CTR) in the THz region, combined with data-driven analysis, is presented. The diagnostic system has been installed at the MAX IV Short-Pulse Facility (SPF), where extensive experimental data have been collected.

The broadband imaging system was designed using optical simulations to study sensitivity to longitudinal profile properties. Experimental CTR images were acquired across a range of machine settings and correlated with reference measurements from a transverse-deflecting cavity. Machine learning techniques (i.e., convolutional neural networks (CNN), ensemble models, transfer learning) were subsequently applied to the CTR image data to infer bunch length and reconstruct longitudinal beam profiles in the femtosecond range. This contribution describes the optical system design, experimental setup, and data acquisition, and presents results demonstrating the method's capability to retrieve longitudinal beam parameters on a single-shot basis.

Simulations indicate that spatial CTR imaging, combined with machine learning, provides a promising, compact, and reliable approach for single-shot longitudinal beam diagnostics, with potential applicability to high-repetition-rate and short-pulse accelerator facilities, for which an experimental demonstration is underway.

Speaker: Ana Guisao-Betancur (University of Liverpool, Cockcroft Institute)

MC01: Beam Charge and Current Monitors

69 A real-time AC current monitoring system for TRIUMF driver accelerators

An AC current transformer (ACCT) is among the most robust non‑interceptive diagnostic tools for real‑time beam monitoring during beam delivery. At TRIUMF, ACCTs are installed in major beamlines, enabling continuous measurements of beam intensity without disrupting beam transport. This work evaluates the performance and operational characteristics of ACCTs used on the facility’s primary accelerator drivers: the electron linac (e‑linac) and the cyclotron. The measured ACCT noise level is on the order of microamperes. Building on this stability, the integration of online ACCT measurements into the Machine Protection System (MPS) is discussed to enable safe and reliable high‑power operation.

Speaker: Hui Wen Koay (TRIUMF)

70 Vector potential-based beam current sensors: applications for Mu2e, and picosecond bunch substructure

We report on a new radiation-hard beam current monitor system based on work originally done to develop timing planes for future collider detectors. In contrast to sensors based on wall currents or toroid inductance, we make use of electric field induced by the electromagnetic vector potential of the beam current as it passes near or through a transmission line (TL), arranged with its dominant TEM or TE10 fields aligned with the current, thus directly coupling to TL modes. For Mu2e, we utilized a TEM parallel-plate TL geometry, since the requirements included measuring the structure of the bunch over ~200ns time scales. We present the design and results of simulated and realized sensors now deployed in the Mu2e beamline. In addition, inspired by this and prior work, we also investigate the use of broadband mm-wave dual-ridge waveguide as a means of measuring beam current substructure of nanosecond bunches down to the tens of picosecond level.

Speaker: Ryan Kim (Fermi National Accelerator Laboratory)

14:40 Break

MC05: Longitudinal Diagnostics and Synchronization

Convener: Hirokazu Maesaka (RIKEN SPring-8 Center)

71 Cavity-based bunch arrival monitor for ultrafast electron diffraction beamlines

Ultrafast electron diffraction (UED) is a powerful tool for probing transient structural dynamics, however, its temporal resolution is fundamentally limited by laser-electron beam time of arrival jitter. To address the need for sub-10 femtosecond precision, we utilized a 4.76 GHz two-cell cavity-based Beam Arrival Monitor (BAM) designed to achieve high sensitivity at extremely low bunch charges. We report experimental results from the UCLA PEGASUS beamline, where time of arrival beam tests demonstrated strong sensitivity to beam-induced RF signals. Crucially, the cavity phase serves as a high-fidelity timing observable. While we demonstrate exceptional charge sensitivity capable of measuring bunch charges below 0.5 fC, the optimal timing sensitivity required for precision synchronization is obtained at higher bunch charges. Building on these findings, ongoing work integrates the BAM with a state-of-the-art RFSoC digital Low-Level RF (LLRF) platform. By combining a multi-core ARM processor, FPGA, and high-speed ADCs and DACs on a single chip, this architecture significantly extends diagnostic capabilities, enabling multichannel processing, low-latency deterministic feedback and AI/ML real-time control. This framework lays the foundation for deploying physics-informed machine learning models to suppress noise and correct drift beyond conventional hardware limits, paving the way for robust sub-10 fs synchronization in next-generation UED experiments.

Speaker: Wei Liu (Accelerator Technology and Applied Physics Division, Lawrence Berkeley National Laboratory)

72 Photonic lanterns: flexible, efficient, and affordable radiators for novel diagnostics at picosecond resolution

To measure longitudinal profiles at picosecond resolution, optical diagnostics using Cherenkov Radiation (ChR) must generate light with sufficient intensity, ensuring propagation to a detector with minimum dispersion and attenuation. Existing radiators (ChR generation media) exhibit a trade-off between ChR intensity and dispersion, with larger radiators creating higher ChR intensity at the cost of increased dispersion, and smaller radiators suffering the opposite. Conventional multimode optical fibers constitute flexible ChR radiators allowing convenient light outcoupling, but suffer a similar trade-off. We demonstrate a novel radiating light guide, the photonic lantern, to overcome this problem. Developed at SAIL (Sydney Astrophotonic Instrumentation Laboratory), the multimode lantern tip is irradiated with electrons at the PEER facility (Pulsed Energetic Electrons for Research) of the Australian Synchrotron, emitting ChR at intensities comparable to conventional multimode optical fibers. Multimode ChR is fed to 300 single mode cores via an adiabatic transition for dispersion-free transport to a streak camera. Bunch profiles from the lantern are compared to those from conventional optical fibers. Advantages of fiber radiators are retained, such as greater flexibility, relative affordability and convenient outcoupling, while dispersion characteristics are improved. We highlight potential to retrofit the photonic lantern at existing IR-FELs, alongside S-band and X-band linacs.

Speaker: Paarangat Pushkarna (The University of Melbourne)

MC01: Beam Charge and Current Monitors TUTB

73 High-intensity heavy-ion beam diagnostics over a nine-order-of-magnitude dynamic range

Monitoring high-power heavy-ion slow extraction requires instrumentation capable of handling extreme intensity gradients. This paper reports on the design and performance of a beam diagnostic system developed to characterize $^{209}\text{Bi}^{31+}$ beams at $850\text{ MeV/u}$, covering a wide dynamic range from $10^{1}$ to $2 \times 10^{10} \text{ pps}$. To achieve this, a composite detector architecture was implemented, integrating plastic scintillators, Ionization Chambers (IC), and Secondary Electron Intensity Monitors (SEIM) for intensity measurements, alongside strip ionization chambers for profile monitoring. The study focuses on the calibration strategies and linearity management required to bridge overlapping sensitivity regions and mitigate saturation effects at high flux. Bench tests and beam experiments validate the system's high bandwidth and noise suppression, enabling the first detailed observation of the beam's 3D microstructure at these intensities. Results demonstrate that the instrumentation successfully maintains linear response across nine orders of magnitude, providing a robust tool for optimizing nanosecond and microsecond beam spill structures in high-intensity accelerators.

Speaker: Tong Liu (Institute of Modern Physics, Chinese Academy of Sciences)

Tuesday Poster Session 2

74 Design and simulation of a resonant stripline transverse feedback kicker

This paper presents a method to improve the shunt impedance of a transverse feedback kicker within a constrained longitudinal space. By modifying the internal geometry of the electrodes to transition from a conventional wideband traveling-wave design to a quasi-resonant configuration, the efficiency of the kicker is enhanced at the expense of operational bandwidth. The proposed design aims to provide a higher transverse kick for a given input power without increasing the total length of the device. The paper describes the structural modifications, discusses the underlying physical principles, and provides preliminary simulation results to verify the feasibility of the approach.

Speaker: Xiaoyu Liu (Institute of High Energy Physics)

75 Enhanced reconstruction method employing machine learning for electro-optic sampling of shaped high energy electron beams

Electro-optic sampling (EOS) is an attractive technique for non-destructive measurement of electron bunch profiles. Its importance continues to grow for next generation high-energy accelerators, where intercepting diagnostics are no longer viable. In EOS, the measured signal corresponds to the phase retardance, rather than a direct measurement of the electric field. The electro-optic (EO) response acts like a finite-bandwidth transfer function, which attenuates high-frequency components and makes the reconstruction ill-conditioned. In this work, we investigate machine learning (ML) as a data-driven approach to improve reconstruction of the underlying THz pulse from EOS measurements. While the fundamental information content remains constrained by the EO response, the ML framework leverages prior knowledge of physically plausible pulse structures to stabilize the inversion.

Speaker: Spencer Kelham (Northern Illinois University)

76 A study on beam orbit stability improvement in the BEPCII storage ring via neural network and filtering techniques

BEPCII, the upgrade project of the Beijing electron positron collider, is operated not only as a collider for high energy physics research but also as a synchrotron radiation source. Orbit stability is critical for high performance operation. In recent years, an orbit feedback method leveraging neural network was studied and tested on BEPCII, demonstrating improvements in orbit stability. However, it’s observed that the orbit stability is still significantly affected by the noises of BPM data. To eliminate the impact of noises, the Kalman filtering method is introduced into the orbit feedback system and combined with the existing neural network framework, creating a dual neural network orbit feedback system. This approach led to further improvements in overall orbit stability.

Speaker: Jiuqing Wang (Institute of High Energy Physics)

77 AI-controlled SRF linac based on phase-locked CW magnetrons

We propose an AI-driven control architecture that sustains resonance among magnetrons and SRF cavi-ties, enabling efficient accelerator operation. Injection locking will be achieved by extracting pick-up signals from normal-conducting cavities integrated into a beamline with the main SRF cavities. A bunched elec-tron beam behind injector section will excite these resonators to deliver controllable extracted RF power to the magnetrons. This approach eliminates the need for external RF sources to obtain phase locking. AI will optimize cavity tuning to preserve the phase-locked condition, and AI-driven Ferro-Electric Tuners (FRTs) will compensate microphonics and other detun-ing effects in accelerating SRF cavities. We highlight the complexity of controlling FRTs, which require both fast (sub-millisecond) bias-voltage signals and slower temperature-driven adjustments from an integrated chiller. Fast control covers microphonics compensa-tion and magnetron power amplitude, while tempera-ture control expands tuning range to compensate for slow fluctuations. A human-in-the-loop approach is impractical for such a system. We therefore plan to develop and deploy high-fidelity AI-driven digital twins to enable dynamic, in-situ linac control and op-eration, ultimately reducing linac cost, improving beam quality, and increasing reliability by mitigating undesired trips.

Speaker: Sergey Kuzikov (Thomas Jefferson National Accelerator Facility)

78 Background and timing from the LANSCE longitudinal profile monitor

For high power ion accelerators such as the machine at the heart of the Los Alamos Neutron Science Center (LANSCE), beam “tails” and “halo” can pose significant problems. Such small fractions of the beam current are easy to lose and difficult to measure, yet can contain enough charge to generate significant radiation; thus, halo and tails can pose a direct threat to instrumentation through radiation, and impact maintenance due to activation. At LANSCE, we have nearly completed installation of a laser-neutralization based bunch length diagnostic. When complete, we will use a ~1 ps pulse length laser to strip to H- secondary electron. We will slew the phase of the laser with respect to the H- bunch to measure the bunch temporal profile. Currently, we can characterize background signals in the beam tunnel and test operation and timing for all components except the laser. We present an installation update and initial findings.

Speaker: Heather Andrews (Los Alamos National Laboratory)

79 Beam position stability and global orbit feedback system at SESAME

Since becoming a user facility in 2017, SESAME has
employed a Slow Orbit Feedback (SOFB) system, implemented in MATLAB, to stabilize the global orbit of the Storage Ring (SR) at a low correction rate of 0.2 Hz. However, achieving improved synchrotron performance requires sub-micron beam orbit stability across a broader frequency
range, extending up to 100 Hz. To address this, the SOFB
system has been upgraded to operate at 10 Hz sampling rate
using an in-house developed control system written in C,
marking an important first step toward a Fast Orbit Feedback
(FOFB) system. This paper presents the upgraded SOFB,
its performance, beam position st ability studies and preliminary studies toward the development of a full FOFB system,
including the necessary system requirements and potential
implementation strategies

Speaker: Hussein Al-Mohammad (Synchrotron-Light for Experimental Science and Applications in the Middle East)

80 Bunch Length Measurement using Beam Spectrum at ALBA

The ALBA Synchrotron is preparing its upgrade to ALBA II, requiring reliable diagnostics of longitudinal beam properties. Bunch length measurements are currently performed using a streak camera, providing a precise determination of the bunch profile. In addition, a new method has been implemented to deliver complementary and more readily available measurements during routine operation. The method is based on the analysis of the frequency spectrum of BPM button signals. It provides relative bunch length measurements calibrated against streak camera data. This work shows the relative bunch length measurement and extends the frequency spectrum analysis to the theoretical scenarios anticipated for ALBA II.

Speaker: Laura Torino (ALBA Synchrotron (Spain))

81 Bunch length measurement with a stripline fast Faraday cup at the end of SCL3 and the KoBRA beamline in RAON

RAON is a heavy-ion accelerator facility that delivers beams with various energies to experimental areas. To measure bunch lengths shorter than 1 ns, a 50 Ω-matched stripline fast Faraday cup (FFC) was developed. The FFC signal was amplified using a 4 GHz broadband amplifier with a gain of 42 dB and measured with an oscilloscope having a sampling rate of 25 GS/s and a bandwidth of 4 GHz. The developed FFC was installed in the straight section at the downstream end of SCL3 and in the KoBRA beamline. Bunch-length measurements were carried out using an Ar 9+ beam with a current of 40 μA and a pulse width of 100 μs. This poster presents the bunch-length measurement results obtained with the stripline fast Faraday cup at the downstream end of SCL3 and the KoBRA beamline.

Speaker: Jangwon Kwon (Institute for Basic Science)

82 Bunch-by-bunch feedback subsystems to measure beam characteristics on SuperKEKB rings

At the SuperKEKB collider, many challenging phenomena arise from the high current and narrow bunch spacing. In particular, there are urgent issues that require clarification and resolution, such as the sudden beam loss (SBL) phenomenon, in which the beam suffers significant loss within the first one or two circuits, and the betatron tune shift along the bunch train due to wake fields. Using the digital bunch feedback system, we have employed several monitors to measure beam characteristics without disrupting the bunch feedback function. This paper presents the subsystems with several examples of measured results.

Speaker: Makoto Tobiyama (High Energy Accelerator Research Organization)

83 Bunch-selective diagnostics of operational H⁻ beams enabled by single picosecond laser pulses

Particle beams in accelerators exhibit temporal structures from picoseconds to milliseconds, reflecting processes of generation, capture, acceleration, and stabilization. At the SNS linac, the H⁻ beam displays a hierarchical time structure governed by RF phase stability, beam chopping, and pulsed operation. Bunch-resolved measurements enable detailed studies of transient beam dynamics and support model validation for beam loss mitigation.

We demonstrate bunch-selective diagnostics using a laser wire system driven by picosecond pulses. The laser pulse structure and timing are precisely tailored to probe individual H⁻ bunches at selected locations within a macropulse or mini-pulse using a single laser pulse. Combined with a laser comb technique, transverse and longitudinal profiles of multiple bunches are acquired simultaneously in a single scan. This approach enables high-precision characterization of intra–mini-pulse beam evolution, revealing fine temporal structures beyond conventional diagnostics. System implementation and measurement performance are presented.

Speaker: Yun Liu (Oak Ridge National Laboratory)

84 Canadian Light Source PicoScopes

In 2025, the Canadian Light Source (CLS) began replacing some traditional oscilloscopes with digital oscilloscopes from Pico Technology. These headless oscilloscopes have been exposed via process variables (PVs) in an Experimental Physics and Industrial Control System (EPICS) Input/Output Controller (IOC) application. This allows secondary control, visualization, and analysis software to monitor various system parameters and beam diagnostic equipment.

Speaker: Chloe Mertin (Canadian Light Source (Canada))

85 Cavity-based beam charge and arrival time monitor

Characterizing bunches non-destructively is extremely useful in a variety of accelerator use cases. In single-event effects testing with pulsed electrons, the bunch charge (~1-10 fC) needs to be measured precisely so that the microelectronic device response can be well correlated with the delivered dose. Cavity-based beam monitors, based on wake field excitation from the beam, offer a highly sensitive single-shot measurement for both charge and time of arrival. Recent experiments at UCLA PEGASUS have shown sub-fC sensitivity, with ongoing work to understand the theoretical and practical limits for measuring the bunch charge. The wake field signal also gives access to the time of arrival information for the bunch, paramount for probing temporal dynamics in schemes like ultrafast electron diffraction. Efforts at UCLA are ongoing to understand the sensitivity limits of the arrival time monitor, making using of a two-pulse scheme to isolate the resolution of the cavity monitor and acquisition system. Further progress will require advanced acquisition hardware to reduce noise or a cavity redesign to increase the outcoupled signal.

Speaker: Atharva Kulkarni (Particle Beam Physics Lab (PBPL))

86 Design and development of a fast Faraday cup for bunch length measurements in the CSNS MEBT

For the CSNS-II upgrade, which targets a beam power of 500 kW by increasing the linac output energy from 80 MeV to 300 MeV and the peak current to 50 mA, the Medium Energy Beam Transport (MEBT) line will undergo a major redesign. The new MEBT features an optimized lattice with enhanced collimation to effectively manage the stronger space charge effects at higher beam intensity. Precise bunch length measurement is essential for optimizing the RF buncher cavities to achieve proper longitudinal compression and ensure good beam matching into the downstream Drift Tube Linac (DTL). To meet this requirement, a 20 GHz bandwidth fast Faraday cup (FFC) has been designed for the CSNS MEBT. The design incorporates impedance-matched structures and a minimized drift gap to mitigate the low-β effect while maintaining the bandwidth. To mitigate the high frequency signal transmission losses in long coaxial cables an electro-optical module has been adopted to transmit high frequency signal. Additionally, a cable correction scheme also has been studied for the signal transmission over long distance coaxial cable.

Speaker: Muhammad Abdul Rehman (Institute of High Energy Physics)

87 Design and Monte Carlo simulation of a high-power beam dump for LEDP in the CSNS-II linac

The beam commissioning of the CSNS-II Drift Tube Linac (DTL) requires a beam dump capable of absorbing high-intensity H⁻ beam pulses with energies of 20–80 MeV and an average beam power of up to 200 W at 1 Hz. A major challenge is to mitigate both the severe thermal load on the dump itself and the radiation impact on the downstream superconducting section. To address these issues, a Faraday dump was designed with a TZM (Ti-Zr-Mo) alloy entrance foil and cup to tolerate thermal shock, a Red-8 isostatic graphite block for heat sink and dissipation, and an additional shielding layer(W/W85Cu15) to reduce downstream activation. The calculated energy deposition distributions were further imported into thermal conduction analysis to assess the temperature field and structural response of the dump with COMSOL. The results show that the TZM-graphite configuration effectively reduces the peak power density and prevents melting or excessive thermal deformation under the design operating conditions. In addition, W85Cu15 provides better overall shielding performance than pure tungsten in suppressing downstream proton and neutron flux, while also offering improved thermal conductivity and manufacturability. The residual dose rates behind the dump remain within the safety limits for superconducting linac operation. These results demonstrate that the proposed design satisfies the requirements for DTL beam commissioning and provides effective protection for downstream components.

Speaker: Renjun Yang (Institute of High Energy Physics, Chinese Academy of Sciences)

88 Design of beam arrival time monitor for beam-driven plasma wakefield accelerator project

In beam-driven plasma wakefield acceleration (PWFA) facilities, highly precise measurement of beam arrival time is crucial, as it is a key physical parameter determining acceleration efficiency and beam quality. Two beam arrival time monitors (BAMs) are installed in the PWFA beamline 2 at the Institute of High Energy Physics (IHEP), each monitor employs a dual cavity design operating in the TM010 mode. The radio frequency signals from individual cavities are down-converted to obtain intermediate frequency signals, whose phases encode the beam arrival time at the respective cavity location. By mixing the output signals from the two cavities with different resonant frequencies, the beam transit time between the cavity positions is determined. This paper presents the design and offline test results of the BAMs, along with an overall evaluation of the system resolution based on laboratory measurements.

Speaker: Xiaoyu Liu (Institute of High Energy Physics)

89 Design of the stripline kickers for Materials Science Synchrotron Light Source

The Materials Science Synchrotron Light Source is a newly proposed accelerator facility, aimed at providing a powerful platform for materials science research. Two kickers are installed in the booster for tune measurement, while another two kickers in the storage ring serve for transverse feedback and tune measurement. All four kickers adopt a stripline‑type structure. This paper presents the design of these kickers.

Speaker: Longwei Lai (Shanghai Advanced Research Institute)

90 Development of a compact Cryogenic Current Comparator for CRYRING@ESR at GSI

The Cryogenic Current Comparator (CCC) is a non-interceptive beam diagnostic device for measuring low-intensity ion beams down to the nanoampere range. This work focuses on developing a compact CCC system for CRYRING@ESR at GSI, where installation space inside the ring is limited. A key constraint is integration close to a correction solenoid and dipole magnet, where magnetic perturbations can affect the SQUID readout.

The study investigates a compact CCC design adapted to the mechanical, cryogenic, and magnetic constraints of CRYRING. The short detector length and pickup-coil design directly influence current resolution, which has to be investigated in detail. Special attention is given to detector positioning, magnetic shielding, vibration reduction, and thermal stability, since these factors also affect resolution and reliability. Concerning thermodynamic properties a CCC Simulation framework is being developed to estimate the cryogenic standing time, heat loads, helium consumption and operational stability of the compact system.

The goal is to optimize the compact CCC geometry and cryogenic support system for reliable operation in CRYRING, future nanoampere-level beam current measurements and compact CCC diagnostics for FAIR.

Speaker: Sankalp Shinde (Friedrich Schiller University Jena)

91 Development of an iGp12-based bunch-by-bunch current and lifetime diagnostic system for current/lifetime-aware top-up injection at PLS-II

Stable top-up operation requires bunch-by-bunch fill-pattern control as well as total beam current regulation. In PLS-II, time-based top-up injection makes it difficult to promptly identify under-filled buckets, over-filled buckets, or abnormal injection shots, which can cause fill-pattern modulation and beamline micro-flux variations.

We developed a bunch-by-bunch current diagnostic IOC using the SUM signal of the Dimtel iGp12 feedback processor. The BPM SUM signal is down-converted to baseband, converted into per-bucket amplitudes, baseline-subtracted, and calibrated to the DCCT total current, providing a robust fill-pattern monitor without additional photodiode hardware.

An Injection Difference Viewer visualizes shot-by-shot current increments versus bucket number and injection step, enabling identification of missing shots, under-filling, over-filling, and abnormal injection sequences. A lifetime IOC also estimates train, camshaft-bunch, total-current, and DCCT-based lifetimes using stitched fitting under top-up operation.

This infrastructure supports the transition from time-based top-up injection to current/lifetime-aware bucket selection for flatter fill-pattern control and future AI-assisted top-up operation.

Speaker: Si-Won Jang (Pohang Accelerator Laboratory)

92 Development of bunch-by-bunch feedback electronics

This paper presents the design of a parameter-tunable turn-by-turn feedback system, integrating front-end analog and digital signal processing modules onto a single functional board. Tailored for storage rings such as BEPCII and HEPS, the system is capable of filtering the revolution frequency and adjusting the feedback phase within 0.5 ms to generate correction signals. Building upon existing self-developed feedback electronics and the IHEP digital BPM system, this study investigates signal down-conversion, sampling theory, clock phase-locked loops (PLL), and high-speed circuit design. We selected optimal ADC and DAC chips based on BEPCII parameters and designed a custom Analog Front-End (AFE) board to acquire down-converted sampling data. Furthermore, various Finite Impulse Response (FIR) filters were modeled in MATLAB. By comparing the frequency responses of filters designed via the Least Squares method and the Window method, optimal coefficients were determined and implemented in the FPGA. Crucially, the system addresses the phase relationship between the pickup and the kicker. Since the feedback signal requires a specific phase shift relative to the BPM signal (nominally 90°) plus the beam transit phase, the design incorporates a tunable coefficient mechanism. This allows for precise adjustment of the filter's phase-frequency response to ensure the correct feedback phase is achieved.

Speaker: liang xu (Institute of High Energy Physics, Chinese Academy of Sciences)

93 Development of new fast orbit feedback system for the SSRF storage ring

A Fast Orbit Feedback (FOFB) system is being developed for the SSRF storage ring to suppress beam orbit disturbances and improve beam stability. The system adopts a distributed architecture based on FPGA and EPICS, integrating beam position monitor (BPM) data acquisition, orbit correction computation, and corrector magnet control within a real-time feedback loop. The feedback algorithm is based on the response matrix method. The pseudo-inverse of the response matrix is calculated offline using Singular Value Decomposition (SVD) and loaded into the controller. During operation, orbit deviations measured by BPMs are processed in real time, and the corresponding corrector strengths are calculated through matrix-vector multiplication implemented in FPGA programmable logic. The processing system manages system configuration, diagnostics, and communication with the EPICS control system, while latency-critical computations are executed in dedicated hardware. An EPICS soft IOC and GUI have been developed for system configuration, beam orbit monitoring, and system status monitoring.

Speaker: Longwei Lai (Shanghai Advanced Research Institute)

94 Development of RFSoC-based transverse bunch-by-bunch feedback and real-time betatron tune monitor for SPring-8-II

Strong suppression of beam instabilities and real-time betatron tune monitoring are crucial for the 4th-generation light source, SPring-8-II. We developed a transverse Bunch-by-Bunch Feedback (TBBF) and a real-time betatron tune monitor based on the AMD RFSoC platform to replace the current legacy systems. Integrating ADCs/DACs, an FPGA, and ARM processors, the RFSoC enables low-latency processing and seamless integration into the accelerator control system. The TBBF performance was validated via beam studies at the SPring-8 storage ring. Grow-damp experiments showed a damping rate of 10 ms⁻¹, which meets the requirement for SPring-8-II. Furthermore, a high single-bunch current of 7 mA was successfully stored with the TBBF, which is 2.5 times higher than that without the feedback. These results show this TBBF is promising to be applicable to SPring-8-II. The RFSoC’s Real-time Processing Unit embeds a phase-locked loop (PLL) for automatic betatron tune tracking. It locks the 90-degree phase difference between a forced-oscillated bunch and its excitation source. This approach was validated against the conventional sweep method, showing high consistency with 10⁻³ precision. We demonstrated the PLL successfully tracks betatron tune shifts when varying the quadrupole magnet parameters. The real-time monitor has the potential for tune feedback to stabilize the ring's operating point.

Speaker: Toshinori ABE (Japan Synchrotron Radiation Research Institute)

95 Development of the Cryogenic Current Comparator for heavy ion accelerators

The Cryogenic Current Comparator (CCC) was proposed and first tested as a low intensity diagnostics in the mid 90s at GSI. After proof of principle, the device was considered having high potential but also high costs and difficult handling. Nonetheless, further research work was done to optimize pickup material and operation stability. With start of the plannings for FAIR, the necessity for a nA diagnostics for slow extracted beams and exotic ions in storage rings became evident again. Since 2014 a collaboration of specialized institutes worked on the optimization of the device, with GSI and CERN being the related accelerator laboratories. In the frame of this collaboration, all relevant properties have been investigated and modified, such as magnetic shielding, pickup materials, SQUIDs and SQUID circuit and least the cryogenic support system. In parallel, commercial electronics became available, providing better performance and control than homemade SQUID electronics. During the research work different types of CCC have been invented to achieve effective shielding, highest possible current resolution and maximum system robustness. As preliminary conclusion of this work, the axial shield Dual Core CCC (DCCC) has been designed, built and successfully tested with beam. It will be installed in the FAIR transport sections and rings as well as in the CERN SPS extraction lines. In this contribution we give an overview of the development work for the CCC.

Speaker: Thomas Sieber (GSI Helmholtz Centre for Heavy Ion Research)

96 Digital interference suppression methods for nA intensity measurements with the cryogenic current comparator

Highly sensitive measurement systems based on Cryogenic Current Comparators (CCCs) and SQUID sensors enable the detection of extremely small currents and weak spill signals. However, the beam signal is often superimposed by mechanical and electrical disturbances, such as the 1.4 Hz interference introduced by the helium reliquefier, making reliable signal extraction challenging.
This work investigates and compares interference suppression methods for CCC/SQUID-based measurements. The study combines transfer-function-based simulations derived from previously identified system transfer functions* with measurement data. The approaches include conventional filtering techniques, transfer-function-based disturbance prediction, and methods using redundant sensor information to suppress correlated interference components. In addition, combinations of these approaches are investigated. Performance is evaluated using metrics such as the Signal-to-Interference Ratio (SIR), signal amplitude preservation, and spectral similarity to a reference signal. Representative results show that a combined processing approach can improve the SIR from −3.0 dB to +6.9 dB while increasing the spectral similarity to the reference signal from 0.42 to 0.94.
The results demonstrate the potential of combining complementary interference suppression techniques for high-sensitivity CCC/SQUID measurements.

Speaker: Svenja Kolbe (Ernst Abbe University of Applied Sciences Jena)

97 Electro‑optical longitudinal bunch profile monitor at FLUTE: from commissioning to first bunch profile measurements

The Ferninfrarot Linac- und Test-Experiment (FLUTE) is a linac-based accelerator test facility at the Karlsruhe Institute of Technology (KIT). It is designed for electron bunches with energies up to 90 MeV over a wide range of bunch charges, tailored to a variety of accelerator studies. Its bunch compressor enables bunch length adjustments and is designed to compress the bunch length towards the femtosecond scale, providing a suitable platform to test and develop beam diagnostics for ultra-short bunches. An electro-optical (EO) bunch profile monitor is installed at FLUTE to provide non-destructive single-shot longitudinal bunch profile measurements and support R&D of EO methods towards a femtosecond-scale diagnostic. This contribution discusses the commissioning of the electro-optical spectral-decoding setup at FLUTE and presents the first measurements of bunches at 30 MeV to 40 MeV with different lengths to serve as a base line for further diagnostics development.

Speaker: Micha Reissig (Karlsruhe Institute of Technology)

98 Experimental study of a Cherenkov diffraction radiation bunch length monitor using Schottky detectors

A non-invasive bunch length monitor based on Cherenkov diffraction radiation (ChDR) has initially been designed for 150 MeV, sub-ps bunches and recently is also being considered for the AWAKE Run 2c 18 MeV seed electron beam line to measure bunches in the ps range. The monitor consists of dielectric radiators that generate polarization radiation when an electron bunch passes in close proximity to them. Coherent ChDR emitted from the radiators is measured by zero-bias Schottky detectors operating in different frequency bands, enabling a relative measurement of the RMS bunch length. We present measurements performed at the CERN Linear Electron Accelerator for Research (CLEAR) characterising the bunch length dependence of the diode response across two frequency bands, 50-75 GHz and 90-140 GHz, for bunch lengths of 0.4-2.5 ps.

Speaker: Jack McGunigal (University of Manchester)

99 Experiments with MEMS accelerometers at FLUTE@KIT

The development of minimally invasive beam diagnostics to characterise Ultra-High Dose Rate (UHDR) beams is essential in the increasingly relevant field of FLASH Radiotherapy. In this work we report on the results of irradiation experiments with the BMA580 Micro-Electro-Mechanical Systems (MEMS) accelerometer sensor at the in-air experimental section of the Ferninfrarot LINAC- und Test-Experiment accelerator (FLUTE@KIT) at the Karlsruhe Institute of Technology. The basis of our investigations is to explore the potential of such sensors in UHDR-suitable diagnostics.

Speaker: Micha Reissig (Karlsruhe Institute of Technology)

100 Femtosecond-scale bunch compression and arrival-time diagnostics at the MAX IV linear accelerator

This contribution describes design and results obtained with newly installed longitudinal diagnostics at the MAX IV linear electron accelerator: a Bunch Compression Monitor (BCM) and an Electro-Optical Arrival Time Monitor (EO-BAM). Both are part of a concerted effort to improve longitudinal stability to a level commensurate with the shortest available bunch lengths of about 3 fs. As MAX IV is a small lab with limited resources, these diagnostics build on existing, proven designs.

The BCM measures the intensity of diffraction transition radiation generated by a copper radiator. Holes allow the electron bunch to pass undisturbed. A ZnSe vacuum window, a number of THz filters and a LiTaO3 pyroelectric detector yield sensitivity for bunch lengths from hundreds down to a few femtoseconds. The installation location allows absolute comparison against a high-resolution transverse-deflecting cavity.

The EO-BAM is based on an 40 GHz bandwidth electrode pick-up design from DESY and can use fibre-transported reference laser pulses from both the recently commissioned 1550 nm laser-synchronisation system and from the 800 nm pump-probe experimental laser oscillator. At 800 nm a Treacy pre-stretcher counteracts dispersion in the fibre connections, at 1550 nm the laser link is already dispersion compensated. Free-space optical delays control temporal overlap in two commercial EO modulators, one for each wavelength.

Speaker: Oliver Grimm (MAX IV Laboratory)

101 Filling pattern monitor: An upgraded photon-based diagnostic system for SLS 2.0

The commissioning of the next-generation Swiss Light Source, SLS 2.0, at the Paul Scherrer Institut (PSI) required advanced diagnostic tools*. Built on established Avalanche Photodiode-based (APD) fill pattern monitoring principles used in previous storage ring diagnostic systems, we present an upgraded Filling Pattern Monitor (FPM) designed specifically for real-time evaluation of the SLS 2.0 fill pattern. The bunch frequency is ~500 MHz, and the APD produces pulses in the order of 300 ps. The FPM is built around CompactPCI-Serial hardware** and a commercial ADC FMC board. The ADC samples the signal from the APD with a time-interleaved sampling rate of ~96 GSPS, providing 192 samples per bucket resolution. The system processes the waveform in real time to calculate the bucket charge distribution for the entire SLS storage ring at a frequency of 3 Hz. The fill pattern is derived using four distinct methods. While each method can independently calculate the charge distribution, this implementation employs a hybrid approach, integrating selected method outputs at different stages of the data processing pipeline. Synchronized with the machine timing system, the FPM outputs measured fill pattern data at a latency of <40 ms relative to the selected trigger. These data can be used directly by downstream systems such as the Fill Pattern Feedback (FPFB)*** as needed.

Speaker: Daniele Felici (Paul Scherrer Institute)

102 First operation experience with the SLS 2.0 fast orbit feedback system

The upgraded Swiss Light Source storage ring, SLS 2.0, has employed a newly developed fast orbit feedback (FOFB) system since July 2026. This paper reports on the first year of operational experience and the resulting beam stability. We also detail the FOFB system design — including RF frequency correction and the decoupling of synchrotron oscillation frequencies within the FOFB bandwidth — and present measurements of the corrector magnet bandwidth.

Speaker: Boris Keil (Paul Scherrer Institute)

103 High-precision calibration and pulse invariant charge reconstruction in ICT-based diagnostics for C-band FLASH electron linacs

Accurate bunch-charge measurement is essential for FLASH and ultra-high-dose-rate (UHDR) electron accelerators, where therapeutic doses exceeding 40Gy/s are delivered in nanosecond-to-microsecond macropulses. We present the calibration and characterization of a non-intercepting charge measurement chain, based on a Bergoz integrating current transformer (ICT) coupled to a Libera ADC-500 digitizer, developed for the SAFEST compact C-band FLASH linac at Sapienza University of Rome. We show that conventional independent pulse-boundary detection introduces spurious pulse-width-dependent charge errors of up to 40% in the short-pulse regime, arising from ICT-induced pulse broadening rather than true chargeloss. A unified, output-driven integration window, combined with a near-zero-crossing boundary-detection method, removes this artifact entirely, achieving charge-reconstruction repeatability better than 2% and a combined measurement uncertainty of ≤2.2%, over the range 2ns–1000ns and 5pC–75nC, without any pulse-width-dependent correction factor. A segmented single-shot history buffer is further validated for dead-time-free pulse-by-pulse logging at repetition rates up to 200Hz, relevant for clinical FLASH dosimetry.

Speaker: Alessandro Curcio (Sapienza University of Rome, Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Frascati)

104 Injection efficiency measurement at SESAME

Efficient beam injection from the Booster into the Storage Ring is essential for reducing injection time and extending the life time of Microtron’s cathode and auxiliary gun. A range of beam diagnostic instruments including the Parametric Current Transformer (PCT), Fast Current Transformers (FCTs), and Beam Position Monitors (BPMs) have been employed to characterize and monitor the injection efficiency. This study discusses the specific challenges associated with each diagnostic system, as well as the improvements implemented to enhance measurement performance at different stages of injection. Increasing measurement accuracy and optimizing signals from the instruments was necessary in order to better understand the beam behavior over the injection process. These improvements contributed to a more precise evaluation of the overall injection process and lead to a measurable increase in the total injection efficiency in the machine.

Speaker: Hussein Al-Mohammad (Synchrotron-Light for Experimental Science and Applications in the Middle East)

105 Libera Digit 500 as a precise averaged bunch-by-bunch charge readout at ESRF

In an electron synchrotron, precise charge data in bunch-by-bunch domain allows real-time monitoring of bunch-selective charge operations and fill patterns. For ESRF, a new software release for Libera Digit 500 instrument was developed to provide high quality averaged bunch-by-bunch charge data without the need of very fast ADCs. The working principle is based on locking the ADC sampling rate to the RF frequency, which ensures sampling precisely on pulse peaks. The peak value of each individual bunch is integrated over N turns at the turn-by-turn rate, which decreases the noise by a factor √N (typically 600) - tests with beam show clear resolution of 1E-4 losses on a selected bunch. These capabilities allow very precise measurements of the evolution of bunch charges over time and enable applications such as bunch-selective charge variation monitoring over time (scraping, top-up ...), bunch-by-bunch beam position monitoring (4 input channels) and others. The main inconvenience is the strong dependence on the precise synchronization between the instrument's sampling phase and the beam phase. This paper will present the working principles of processing, characterize firsts results with the beam at ESRF and list limitations.

Speaker: Simon Mattiazzi (Instrumentation Technologies (Slovenia))

106 Live modelling of accelerator cavities in a digital twin using PyORBIT

The Spallation Neutron Source is developing a particle accelerator digital twin called Virac (Virtual Accelerator) for testing control room applications and training personnel and machine-learning models. Currently, Virac consists of PyORBIT, a Particle-in-Cell accelerator model, with model parameters read from and written to an EPICS server. As part of being a true digital twin, Virac maps the model parameters to the parameters as seen by operations. While this is straightforward in some cases, acceleration phase of the cavities requires determining the relationship between the reported operational phase and the physics model phase of each cavity. This is a report of how the relationship between these phases is determined for Virac, enabling online modelling of the acceleration cavities.

Speaker: Brandon Cathey (Oak Ridge National Laboratory)

107 Machine-learning reconstruction of injected-beam longitudinal phase space from transient longitudinal motion

We propose a machine-learning method to reconstruct longitudinal phase-space parameters of an injected beam from its transient longitudinal motion. An ELEGANT model of HEPS storage-ring injection simulated 500-turn evolution of the longitudinal distribution while scanning arrival-time offset, relative momentum offset, bunch length, and energy spread. A dataset of 72,000 simulated motion images trained a multi-output ResNet18 model, mapping each 224 x 224 image to the four injection parameters. For 1,000 simulated test samples, R-squared values were above 0.98, with mean absolute errors of 2.31 ps, 0.051 percent, 0.253 mm, and 0.026 per mille. The method was tested using streak-camera measurements of injected-beam motion at the HEPS visible-light beamline under eight RF-frequency settings. After matching time scale, turn number, intensity, and image size, the predicted energy offset showed a reasonable correlation with the expected RF-frequency dependence, and the predicted bunch length and energy spread were broadly consistent with streak-camera estimates. These preliminary results suggest that transient longitudinal motion images can support rapid diagnostics of injected beams.

Speaker: Dechong Zhu (Institute of High Energy Physics)

108 Measurement of neutron energy spectra and angular distributions using activation foils at NDPS of RAON

Rare Isotope Accelerator complex for On-line experiments (RAON) is a heavy-ion accelerator facility designed to provide stable and rare isotope beams in Korea. Nuclear Data Production System (NDPS) is one of the experimental systems at RAON and provides neutron beams for nuclear data measurements and other applications. At NDPS, an Ar-40 ion beam with an energy of about 18 MeV/u is delivered onto graphite or tantalum targets to produce neutrons. The activation foil method was used to measure the neutron fluence and the energy spectrum from the targets. Several activation foils, sensitive to different energy ranges, were used to reconstruct the neutron energy distributions. The foils were placed at angles from 0 to 90 degrees to obtain the angular distribution of the neutron fluence. In this presentation, the energy and angular distributions of neutron beams generated by the Ar-40 ion beams and each target will be presented.

Speaker: Sinchul Kang (Institute for Basic Science)

109 Modernising the ISIS ideal extract buffer unit

The ISIS Neutron and Muon Source is a particle accelerator located at the Rutherford Appleton Laboratory in the UK. Protons are energised to 70MeV through the linear accelerator, before accelerating in the synchrotron to 800MeV; with the facility providing beam at a rep rate of 50 Hz. At this energy, protons are delivered to two target stations to produce neutrons and muons (TS1 at 40 Hz and TS2 at 10 Hz). ISIS has been in operation for over 40 years, and as a result, there are many obsolete legacy systems that are nevertheless critical to ISIS operations. Two legacy systems included were the Riken Trigger Unit and the Extract Trigger Module: these two were updated and combined into the Ideal Extract Buffer Unit. These units are responsible for buffering the Ideal Extract Pulse (IEP), in the absence of the IEP they will provide a 50 Hz backup pulse, as this timing is critical for ISIS operations. The Extract Trigger module provides the IEP to Extracted Proton Beamline 1 (EPB), TS1 and the Riken Trigger Unit. Meanwhile, the Riken Trigger Unit is responsible for the IEP to the diagnostics monitors on EPB2, as well as the Riken Muon Target. The Extract Trigger Module buffered output to the High Energy Transfer (HET) rack on TS1. Here the HET Gated Trigger Box performs AND logic on both the IEP and the intensity. This unit will provide the gated outputs for timing on the TS1 instruments. This box is also obsolete and will be absorbed into this project. This paper will present the process of modernising the electronics of all three systems and combining them into one unit which conforms with modern conventions.

Speaker: Ryan Allinson (ISIS Neutron and Muon Source)

110 New electronics for bunch arrival time monitors

Electro-optical bunch arrival time monitor design at DESY has undergone a wide R&D effort, in order to improve its resolution below 1 fs level. The electronics of the BAM system is responsible for capturing and digitizing the optical pulses that result from laser modulation with the RF signal generated by the passing beam. Development and performance of the new electronics for BAM is presented in detail. The first experience with operation at EuXFEL and FLASH is presented as well.

Speaker: Jiri Kral (Deutsches Elektronen-Synchrotron DESY)

111 New intra-bunch feedback system in J-PARC Main Ring

The J-PARC Main Ring (MR) is being upgraded toward a beam power of 1.3 MW. As the beam intensity increases, higher-frequency intrabunch oscillations are expected to become more pronounced. To suppress these oscillations, the intrabunch feedback (IBFB) system is being upgraded.
The current IBFB system operates at a sampling rate of approximately 110$~$MS/s synchronized with the circulating beam. The upgraded system increases the sampling rate to 576$~$MS/s. As a consequence, the sampling clock is no longer synchronized with the beam revolution frequency. Therefore, the differentiated signal from beam position monitor is integrated over each RF period, where the integration timing is dynamically updated to follow the varying RF period during beam acceleration.
The upgraded IBFB system is currently under evaluation. This poster presents the results of beam tests in the non-acceleration region and simulation studies under beam acceleration.

Speaker: Daiki Nagao (High Energy Accelerator Research Organization)

112 Phase matching of longitudinal hollow electron bunch and ion bunch in a storage ring

In the cooling storage ring, a low-temperature electron beam from the electron cooling device overlaps with a high-temperature ion beam over a finite interaction length at matched average velocities. Through Coulomb interactions, electrons absorb excess thermal energy from the ions, thereby reducing the transverse emittance and longitudinal momentum spread of the ion beam and increasing its phase space density. When cooling a Gaussian-distributed bunched ion beam with a longitudinal hollow electron beam, the longitudinal centers of both bunches must remain matched. This paper presents a phase match scheme for the longitudinal hollow electron beam and the ion beam, comprising bunch measurement, trigger delay setting, phase match monitoring, and a prospective feedback mechanism for automatic correction. The scheme ensures sustained bunch phase match and will be employed in longitudinal hollow electron beam cooling experiments at CSRm, supporting future investigations into the hollow beam cooling dynamics.

Speaker: Xiaodong Yang (Institute of Modern Physics, Chinese Academy of Sciences)

113 Progress on magnetic quadrupole pick-up structure at FRIB

A magnetic quadrupole pick-up structure has been assessed for creation and future use at The Facility for Rare Isotope Beams (FRIB) at Michigan State University (MSU). This device has been optimized for use in the FRIB beamline. Following the optimizations came changes due to manufacturing constraints. Due to the constraints, three smaller, but still suitable, pick-ups will be used instead. Presented here are expected signals and results from particle-in-cell (PIC) simulations of the new pick-ups, as well as expected time-of-flight results and the devices’ response to longitudinal satellites in the beam.

Speaker: Carlos Sarabia-Cardenas (Facility for Rare Isotope Beams)

114 RF-measurements using planar pickups on a printed circuit board down to the present single-digit femtocoulomb detection limit

A novel planar pickup structure on a printed circuit board (PCB) with an integrated combination network has been developed for the electro-optical bunch arrival-time monitors (EO-BAMs) used at the European XFEL and other free-electron laser (FEL) facilities. The design aims for single-digit fs resolution during 1 pC operation in FEL and ultrafast electron diffraction facilities, as well as an overall performance improvement during standard FEL operation. Initial measurements with the first vacuum-sealed demonstrator at the ELBE accelerator proved the viability of this approach, though design trade-offs limited the realization of its full potential. In 2025, an in-air test stand was manufactured to allow for extensive studies of different PCB layouts at the FLUTE accelerator at KIT. In this work, results of two RF measurement series are presented. These radio-frequency (RF) signal measurements were performed down to 80 fC utilizing an 80 GHz real-time oscilloscope adjacent to the beamline. The results surpassed the design goals set for 1 pC bunches. Additionally, through signal averaging, another distinct signal component is visible. Preliminary analysis suggests this is attributable to dark currents with an equivalent bunch charge of less than 10 fC, demonstrating the high sensitivity of the planar pickup design.

Speaker: Bernhard Scheible (Technische Hochschule Mittelhessen)

115 Software-Defined TCSPC with Dynamic BPM Phase Tracking for Multi-Bunch Longitudinal Diagnostics at the HLS-II Storage Ring

Conventional TCSPC bunch-length measurements are degraded by low-frequency longitudinal phase drift. A previously proposed dynamic compensation method based on BPM zero crossing extraction was validated in single bunch mode, but multi bunch operation introduces additional challenges: system delay misassignment and baseline superposition in BPM waveforms. This paper extends the method to the “2 + 35” multi bunch filling mode of the HLS II storage ring. Using a dual channel oscilloscope to simultaneously acquire PMT sin-gle photon pulses and BPM signals, offline processing incorporates dCFD, per bunch zero crossing detection, and a delay scan calibration. Independent longitudinal profiles of all 37 bunches are reconstructed, all exhibiting clean Gaussian single peak shapes with consistent cen-troids. The average bunch length is about 232 ps, with a relative standard deviation of approximately 3% across bunches. The results demonstrate that the method effec-tively eliminates phase drift, requires simple hardware, and is robust for routine multi bunch operation, making it readily transferable to other storage rings.

Speaker: MingDong Ma (University of Science and Technology of China)

116 Toroid diagnostics development for the ISIS MEBT upgrade

The ISIS Neutron and Muon Source at the Rutherford Appleton Laboratory (UK), operated by STFC, is a pulsed neutron spallation facility that employs a rapid cycling synchrotron to accelerate protons to 800 MeV before delivering them to two fixed targets at a combined repetition rate of 50 Hz. As part of an ongoing upgrade programme, a Medium Energy Beam Transport (MEBT) line is being installed downstream of the RFQ in the ISIS pre injector to enhance injection efficiency. This work includes the transfer and adaptation of the existing ISIS Intensity Toroid Monitoring System to ensure reliable, high integrity signal acquisition from the toroids within the upgraded section. To achieve this, several amplifier configurations have been evaluated, and the associated electronic systems have been modified to meet the requirements of the Pre Injector Test Stand (PITS). Additionally, a new toroid is being designed for installation at the end of the MEBT, immediately upstream of Tank 1 in the injector. This diagnostic will be tested, integrated, and commissioned on PITS to validate the MEBT’s performance and readiness for deployment on the operational ISIS accelerator.

Speaker: James FitzGibbon (Science and Technology Facilities Council)

117 Ultra-broadband direct THz detectors for longitudinal electron beam diagnostics

Free‑electron lasers rely on extremely high‑quality, ultrafast electron bunches. Among various diagnostic tools, THz detectors play an essential role in longitudinal diagnostics of electron bunches, such as during the bunch compression process. To address both the existing and future machines, we are developing ultra-broadband THz detectors. Here, we present the development of Schottky diodes and field-effect transistor (FET) detectors operating at room temperature for electron-beam diagnostics. The four aspects of newly developed detectors are: (i) frequency coverage: ultra-broadband single-pixel THz detectors based on both technologies (ii) ultra-wide band IF bandwidth up to ~50 GHz: this enables single shot detection of ps-scale THz pulses with response time in ps range (overcome the pile up issue faced by its counterparts), (iii) experimentally realized bunch compression monitoring capability from single-digit pC to ~ 220 pC: this is essential for precise machine settings for desired beam parameter output, and (iv) Radiation hardness examination of the developed detectors for their smooth operation at accelerator facilities. These detectors are tested at the ELBE facility and can be implemented at other FEL facilities.

Speaker: Bernhard Scheible (Technische Hochschule Mittelhessen)

18:20 SPC Meeting (By invitation)

19:30 Chair's Reception (By invitation)

Wednesday 2 September

MC07: Data Acquisition and Processing Platforms

Convener: Tonia Batten (Canadian Light Source (Canada))

118 Development of a multimode fiber system for remote transverse beam imaging at CLEAR

Remote transverse beam imaging by relaying scintillation light through a multimode fiber (MMF) offers a means of relocating cameras and associated electronics away from accelerator areas with high radiation levels, but practical implementation requires calibration of the fiber relay system. This contribution presents an acquisition platform developed and deployed at CERN's CLEAR facility for collecting images of a Chromox screen under electron beam and controlled laser illumination, using one camera viewing the screen directly and two cameras recording the outputs of two different 15 m MMFs. The system enables automated collection of calibration data using laser illumination, together with electron beam data for subsequent evaluation. During the experiment, the platform archived 268,294 frames across the three cameras, while individual spatial calibration scans could be completed in less than 30 min. The resulting datasets provide calibration and beam data for transverse beam image reconstruction studies.

Speaker: Qiyuan Xu (University of Liverpool, European Organization for Nuclear Research, Cockcroft Institute)

119 Neural network applications for real-time processing

Neural networks (NNs) are commonly implemented on CPU or GPU, which often struggle to meet the strict latency and throughput demands of real-time data processing.
FPGAs offer an alternative: deterministic, low-latency inference directly in the data path.
We present the opportunities FPGA-based NNs offer, how to implement NNs on FPGAs, and how to identify possible use cases.

As our case study, we implemented an NN on the FPGA of a COTS digitizer hardware for real-time determination of particle arrival time in particle counters such as scintillator or semiconductor detectors used at GSI.
When multiple particles arrive at almost the same time, their signals superimpose and the detector response can become non-linear. The presented NN still allows accurate and reliable arrival time detection under these conditions, enabling particle counters to operate reliably at much higher rates.

Speaker: Tobias Habermann (Fulda University of Applied Sciences)

120 A next-generation hybrid pixel detector readout system for beam instrumentation at CERN

The Beam Gas Ionization (BGI) transverse beam profile monitor is a promising diagnostic instrument for the CERN Proton Synchrotron (PS) and Super Proton Synchrotron (SPS) for achieving optimal beam quality and operational efficiency of the accelerator complex. To address new requirements in throughput, reliability, and long-term maintainability, its Hybrid Pixel Detector (HPD) readout system has been redesigned from the ground up. Based on a performant and flexible PCI Express (PCIe) hardware platform, the new architecture combines open-source gateware and software from SLAC National Accelerator Laboratory with CERN software layers: custom C++ readout libraries integrated into the FESA real-time control framework. In addition to being structured to enable clear separation of concerns and robust operation with the current Timepix3-based instruments, the architecture has been designed for extensibility toward future detector technologies such as Timepix4, and reuse in spin-off beam instrumentation projects. This contribution presents the system architecture from a software perspective, design choices based on previous versions, and integration status for PS and SPS operation.

Speaker: Jüri Jõul (European Organization for Nuclear Research)

10:20 Break

MC02: Beam Loss Monitors and Machine Protection

Convener: Jonah Weber (Lawrence Berkeley National Laboratory)

121 Machine protection systems for modern light sources

The PETRA IV project at DESY (Hamburg, Germany) aims to upgrade the PETRA III synchrotron into an ultra-low-emittance light source. Both electron and photon beams can cause damage to accelerator components. The Machine Protection System (MPS) is a critical element of the accelerator’s safety infrastructure, designed to prevent beam-induced damage. It aggregates information from multiple subsystems and intervenes to inhibit beam operation in the event of unsafe or ambiguous machine states.
This contribution presents an overview of the MPS implemented at PETRA III, including long-term operational experience, and discusses further developments and technologies envisaged to meet the demanding requirements of PETRA IV. Additionally, a comparative overview of machine protection systems at other 6 GeV-class light sources is provided.

Speaker: Timmy Lensch (Deutsches Elektronen-Synchrotron DESY)

MC07: Data Acquisition and Processing Platforms

122 An ultra-low latency ATCA-based data acquisition platform for real-time beam current monitoring and fast protection at CSNS-II

The Phase-II upgrade of the China Spallation Neutron Source (CSNS-II) introduces a superconducting linear section, which imposes stringent machine protection requirements by necessitating a total system response time of less than 10 μs. This paper presents a high-throughput, ultra-low-latency data acquisition and processing platform specifically engineered for real-time beam status monitoring and the Fast Protection System. By bypassing standard bus protocol overheads, the architecture employs high-speed LVDS signaling (250 MHz on the backplane) and multi-gigabit serial links (up to 10 Gbps) to achieve deterministic, point-to-point data transmission between front-end modules and the master logic board. During the critical data acquisition process, an RFSoC-based digitizer utilizes 14-bit, 5 GSPS direct RF sampling to capture signals from the low-noise front-end electronics for Fast Current Transformer. To achieve the lowest possible latency, ardware-level DSP algorithms were implemented, including optimized IQ demodulation, pipelined CORDIC, and parallelized fault detection logic. This optimization constrains the processing latency to under 3 μs, enabling an end-to-end system response time of precisely 4.5 μs for superconducting cavity protection. This robust platform provides not only a reliable solution for bunch-by-bunch diagnostics but also a high-performance framework for future AI-driven predictive interlock and edge-computing applications in high-power accelerators.

Speaker: peng zhu (University of Science and Technology of China, National Synchrotron Radiation Laboratory, USTC, China Spallation Neutron Source, Institute of High Energy Physics, Chinese Academy of Sciences)

12:00 Lunch (not included in registration)

Lunch is not provided in the registration fee. Attendees are encouraged to visit the many restaurant locations in the Village of Whislter

MC02: Beam Loss Monitors and Machine Protection

123 Operational experience with the SLS 2.0 beam loss monitoring system

Three types of Beam Loss Monitors (BLMs) have been installed at the Swiss Light Source (SLS 2.0) for both commissioning and routine user operations: Libera BLMs for fast loss detection, RadFETs for dose distribution, and the novel CMOS-based BLM system that has been developed and integrated into the facility's operations. This presentation details the applications of these monitors (eg, injection optimization, and postmortem analysis of loss distributions) and addresses the distinct technical challenges encountered during the first phase and second phase commissioning of the SLS 2.0.

Speaker: Cigdem Ozkan Loch (Paul Scherrer Institute)

124 Design of the LCLS-II HE burn-through monitor readout electronics

The Linac Coherent Light Source II (LCLS-II) is currently undergoing a High Energy (HE) upgrade. This upgrade adds 23 additional cryomodules to the LCLS-II Linac, increasing its energy from 4GeV to 8GeV; which subsequently increases the hard X-ray source photon energy from 5keV up to 12keV. In the photon experimental beamlines, X-ray beam stoppers, located at the entrance to the experimental hutches, can be inserted to absorb the beam indefinitely, up to its full energy. In the event that the beam should somehow breach the stopper, a burn-through monitor (BTM), placed directly in back of the stopper is designed to detect and respond to this occurrence. The BTM detector consists of a YAG:Ce scintillator coupled with a photodiode, which detects the burst of fluorescent photons produced by the breach. The electronics system reads out the photodiode and signals a fault to the LCLS-II Beam Containment System (BCS), interrupting accelerator and FEL beam production. Additional BTMs are added to beam collimators and the photon beam dump. The BTM readout electronics must be simple, reliable and self-checking. This paper describes the design of this electronics system, including its operation and performance.

Speaker: John Dusatko (SLAC National Accelerator Laboratory)

MC10: Special Talks

125 Diagnostics devices, challenges and developments at the SESAME light source

Beam diagnostics play a central role in the commissioning, operation, and performance optimization of synchrotron light sources. Since the start of SESAME’s user operation, a variety of diagnostic systems have been employed to monitor beam properties, evaluate machine performance, and to support the development of advanced control and feedback systems. As operational requirements evolve toward higher beam stability, improved injection efficiency, and enhanced beam characterization, several diagnostic techniques and instrumentation upgrades have been developed and implemented.
This contribution presents an overview of selected diagnostic systems at the SESAME light source, the challenges encountered during their operation, and the developments undertaken to improve their performance. Topics including beam position monitoring and orbit stability studies which support the upgrade of the Slow Orbit Feedback system and the ongoing development of a Fast Orbit Feedback system will be discussed. The talk also discusses the development of an In-Air X-ray Detector for vertical beam size measurements using the hard X-ray from the Storage Ring dipole, providing a complementary tool for beam characterization. In addition, the diagnostic methods used to evaluate injection efficiency are presented, highlighting the use of current transformers and beam position monitors to better understand beam behavior during transfer from booster to storage ring and to optimize the injection process.

Speaker: Hussein Al-Mohammad (Synchrotron-Light for Experimental Science and Applications in the Middle East)

14:40 Break

MC08: Machine Parameter Measurements

Convener: Lorraine Bobb (Diamond Light Source)

126 Complete 6-dimensional phase space reconstruction based on neural networks and differentiable simulation with standard elements

Comprehensive knowledge of the six-dimensional phase space distribution of particle beams is critical for optimizing accelerator performance. While conventional diagnostics such as transverse deflecting cavities enable detailed characterization, they require dedicated hardware and significant beamline space. Generative phase space reconstruction (GPSR) techniques have emerged as a promising alternative for beam diagnostics; however, previous implementations have continued to rely on specialized components.

An experimental implementation and validation of a GPSR methodology based solely on standard accelerator elements, including accelerating cavities and dipole magnets, is presented. The approach enables full six-dimensional phase space reconstruction without the need for dedicated longitudinal diagnostics. Simulation studies and experimental measurements conducted at the Pohang Accelerator Laboratory X-ray Free Electron Laser facility demonstrate successful reconstruction of complex and nonlinear beam structures.

The methodology is validated by predicting independent downstream beam measurements that are excluded from the reconstruction process, with the inferred phase space distributions showing close agreement with the corresponding reference data. These results establish a pathway toward predictive, hardware-efficient beam diagnostics applicable across multiple beamline segments and accelerator facilities.

Speaker: Seongyeol Kim (Pohang Accelerator Laboratory)

127 Estimation of beam parameters with the bunch-shape monitor using the machine learning

The Feschenko-type bunch shape monitor (BSM) is often utilized to measure the longitudinal bunch profile in the hadron linac. In the Japan Proton Accelerator Research Complex (J-PARC) linac, several BSMs are installed to measure the negative hydrogen (H-) ion beam with a peak current of 50 mA, supplied for the high-intensity user operation. As for the notable features of the J-PARC BSM, the 3-MeV H- ion beam in the linac front-end can be measured with the dedicated BSM using the graphite target probe. Thanks to this dedicated BSM, the longitudinal profile can be measured in the low-energy region, where the space-charge force is strongly affected to the H- ion beam. A series of longitudinal profiles was measured with scanning the probe position of the BSM in the horizontal direction, which is the test usage to obtain the two-dimensional profile in the horizontal-longitudinal plain. This 2d profile is expected to contain the interesting information about the correlation of the beam spatial distribution by the space-charge force of the high-intensity H- ion beam. Despite a challenging approach, beam parameters such as the Twiss parameters and the emittance tried to be extracted from a set of 2d profiles under the single quadrupole scan by the machine learning. The convolutional neural network is used to estimate beam parameters of the x, y, and z direction from a series of 2d profiles in the horizontal quadrupole scan. The preliminary result will be reported.

Speaker: Ryo Kitamura (Japan Proton Accelerator Research Complex)

Wednesday Poster Session 3

128 RFSoC-based direct RF sampling scheme with preliminary tests on CBPM & BAM pickups

With the ever-increasing performance of ADC, digital electronics systems based on direct RF sampling have become capable of serving many areas of beam instrumentation. One of the most significant applications is the electronics for CBPM (Cavity Beam Position Monitor) and BAM (Beam Arrival Monitor) pickups, as the signals generated by these pickups are high-frequency signals above 3 GHz. By adopting the direct RF sampling scheme, the complexity of the RF front-end can be greatly reduced, and the high cost of local oscillator (LO) design is also saved.

This paper presents the test results of our direct RF sampling electronics on the CBPM and BAM pickups at the Dalian Advanced Light Source (DALS). The core ADC chip is the XCZU47DR model from the RFSoC family. Under actual beam conditions, the relative transverse position resolution achieved is 0.02235% @ 100 pC, and the time-of-arrival resolution is approximately 19 fs@100pc, well meeting the specifications of the pickups.

Speaker: Ruizhe Gong (Institute of Advanced Light Source Facilities Shenzhen)

129 Development and test of 3.3 GHz cavity BPMs for cSTART at the Swiss Light Source

The Karlsruhe Institute of Technology (KIT) will utilize PSI-developed cavity beam position monitors (CBPMs) for the cSTART storage ring transfer line. This contribution presents beam tests of these CBPMs at the Swiss Light Source injector linac, characterizing performance ahead of cSTART commissioning in 2027. While based on SwissFEL designs, the cSTART CBPMs are adapted for single-bunch operation at 10 Hz with 1–500 pC charge. Resolution requirements for cSTART are <10 μm RMS (10–500 pC) over a 2 mm range, compared to SwissFEL's <1 μm RMS (10–200 pC) over 1 mm. While SwissFEL has six ADCs per 3.3 GHz CBPM to resolve position and charge for individual bunches at 28 ns spacing in the linac and transfer lines, the cSTART version adopts a 3.3 GHz pickup with a loaded quality factor increased from 40 to ~250. This longer signal decay enables more cost-effective 4.9 GHz SwissFEL undulator BPM electronics (adapted to 3.3 GHz); these use three ADC channels per BPM to sample an IF of ~135 MHz, eliminating analog IQ downconversion.

Speaker: Boris Keil (Paul Scherrer Institute)

130 Evaluation of MTCA.4 based Libera Brilliance X BPM electronics at NSLS-II

The MTCA.4 BPM system has been set up using two newly developed modules: DAMC-UNIZUP (by DESY) and 2BPMRTM (by I-Tech). The modules have been installed in a prototype NATIVE server R1 and connected to NSLS-II spare BPMs. To test the performance of the electronics alone, a BPM button signal was split using a four-way splitter and routed to the switching matrix module. Due to tunnel access constraints, the module was installed in the electronics rack rather than in close proximity to the BPM. The system was configured to process two non-overlapping, low-current bunches within a fill pattern independently, while simultaneously providing turn-by-turn readout. Intensity dependence was verified during machine filling, and a 12-hour stability test was performed under user beam conditions. The effectiveness of the external switching module was assessed by introducing controlled physical disturbances to the RF cables. This paper presents the results and the estimated measurement performance of the BPM system.

Speaker: Manuel Cargnelutti (Instrumentation Technologies (Slovenia))

131 Upgrade of the BPM and FOFB electronics for SSRF

Beam Position Monitor (BPM) and Fast Orbit Feedback (FOFB) electronics are critical for ensuring the stability of synchrotron light sources. As part of the intelligent and digital upgrade of the Shanghai Synchrotron Radiation Facility (SSRF), significant enhancements are being made to these electronics, targeting improved beam-position measurement resolution and the integration of precise time-stamping functionality. This upgrade employs MPSoC FPGAs as the system controllers and digital signal processors. The BPM electronics generate a pilot-tone signal to improve measurement resolution and integrate a White Rabbit timing card for accurate synchronization. The FOFB electronics receive high-speed acquisition data from the BPM modules via 10 Gb SFP links and perform real-time feedback computations directly on the FPGA. This paper presents the overall electronics design and details the ongoing upgrade process at SSRF.

Speaker: Longwei Lai (Shanghai Advanced Research Institute)

132 Channel-level anomaly detection for beam position monitors at HEPS with multi-window autoencoder and physics validation

The beam position monitor (BPM) system of the High Energy Photon Source (HEPS) storage ring consists of 578 BPMs distributed over 48 cells. Since BPM faults can affect the fast orbit feedback and beam stability, real-time monitoring with precise localization is essential. This work proposes a channel-level anomaly detection framework that integrates a multi-window autoencoder with a physics-based diagnostic module. The autoencoder captures normal spatial correlations among neighboring BPMs, while the electrostatic constraint inherent to button BPM signals provides an independent cross-check. By analyzing the four electrode signals (A, B, C, D) of each BPM, the system identifies not only the faulty BPM but also the specific electrode channel. Implemented with a GUI for training, offline, and real-time detection, the method is validated on HEPS operational data, successfully detecting and localizing real anomalous signal channels.

Speaker: Xiaoyu Liu (Institute of High Energy Physics)

133 A scalable phosphor-based beam profile monitoring platform at RAON

Beam profile monitoring is essential at every stage of an accelerator beamline, yet deploying dedicated diagnostic systems at each focal plane remains costly and time-consuming. This work demonstrates that a single, standardized software platform, combined with commodity hardware, can provide facility-wide beam profile monitoring with rapid scalability. The platform uses phosphor screens and industrial GigE cameras as a common hardware base. It has been deployed at two beamlines at the RAON heavy-ion accelerator: the KoBRA separator and the NDPS neutron source. Expanding to a new focal plane requires only mounting the hardware, registering the imaging geometry, and minimal software configuration. A single server instance operates all monitoring points simultaneously, preserving independent background models and measurement histories for each. Adaptive rebinning automatically adjusts the analysis granularity to match beam statistics, enabling stable profile measurements from primary beams to low-rate radioactive ion beams without manual intervention. Real-time results are accessible through a web interface and EPICS channel access from anywhere on the facility network. Position measurement performance and operational experience from both beamlines will be presented.

Speaker: Geonhee Oh (Institute for Basic Science)

134 ALS-U beam diagnostics: beam position monitor (BPM) characterization and testing

At Lawrence Berkeley National Laboratory, ongoing work is underway for the Advanced Light Source Upgrade (ALS-U), whose primary objective is to increase photon beam brightness by two orders of magnitude. Achieving this goal requires the delivery of a high-quality electron beam, along with the development of advanced diagnostics to monitor its properties, including beam size, position, current, energy spread, and bunch length. These diagnostics are essential for the tuning, commissioning, and reliable operation of the future facility. Presented here is a report on the development, testing, and characterization of Beam Position Monitors (BPMs), a critical diagnostic for the commissioning and operation of the ALS-U. Due to the complexity of the ALS-U storage ring and small beam size, these BPMs need to be carefully characterized to accurately measure the beam’s position. We performed precision measurements of the electrical properties of the BPMs and associated electronics across multiple units to evaluate fabrication consistency and verify matching performance across units. These measurements support the commissioning of the ALS-U storage ring by providing increased precision of the beam’s position, to help ensure compliance with the stringent requirements of the ALS-U.

Speaker: Jared De Chant (Lawrence Berkeley National Laboratory)

135 An FPGA-based BPM with simultaneous harmonic acquisition and dual RF/White Rabbit synchronization for IFMIF-DONES

The IFMIF-DONES facility requires high-performance BPM electronics capable of providing accurate beam position and intensity measurements while ensuring seamless integration with the facility-wide control and synchronization infrastructure. The joint venture AVS-BTESA, leading the DONES-VATIAC contract with CDTI*, subcontracted SAFRAN for the development of a new BPM electronics architecture to support the validation of accelerator control technologies for future IFMIF-DONES installations.
Based on a modular uTCA platform, the solution includes an AMC for high-speed digital processing and an RTM for analog front-end functions. FPGA-based digital signal processing enables direct RF acquisition and flexible implementation of beam diagnostics algorithms. The BPM electronics supports two complementary synchronization approaches: reference to facility RF signal and compatibility with White Rabbit technology for high-precision timing distribution and event timestamping.
This poster highlights the BPM electronics capability to simultaneously acquire the fundamental and second beam harmonics, which are subsequently separated using digital filtering techniques.
This approach enables flexible operation and facilitates comparative studies between harmonics without requiring hardware reconfiguration. The system also incorporates self-calibration capabilities to improve measurement stability and reduce drifts.

Speaker: Janis DeWitt (Safran Trusted 4D, Inc.)

136 Analog front end for a ultra-short pulse acquisition system at the cSTART accelerator: circuit simulation

This work presents the simulation and conceptual design of an electronic data acquisition system for the characterization of ultra-short pulses generated with high repetition rate. The project is developed within the framework of the cSTART initiative at the Karlsruhe Institute of Technology (KIT) and will be evaluated at the KArlsruhe Research Accelerator (KARA).

The primary focus of this study is the accurate detection and analysis of short time signals with a bandwidth in the order of 100 GHz. Due to their high analog bandwidth, digitization of such signals require very high sample rate digitizers to maintain signal integrity.

To address these challenges, a detailed simulation of the required circuitry is presented, demonstrating how the bandwidth of the analog signal can be effectively reduced, thereby enabling digitization at a significantly lower sample rate. The simulation model incorporates realistic component parameters to ensure a high degree of correspondence between the simulated and the expected physical response. These simulations not only confirm the theoretical feasibility of the approach but also serve as a refined basis for subsequent hardware development. The insights gained from this simulation study lead to a concrete design foundation and enable the realization of an upcoming physical prototype, whose real-world behavior under practical operating conditions will be used to verify and further substantiate the simulation results.

Speaker: Marvin Noll (Karlsruhe Institute of Technology)

137 Bunch‑by‑bunch phase detection and filling pattern measurement via digital I/Q demodulation

A high-precision, bunch-by-bunch (BbB) synchrotron phase detection system has been developed and successfully commissioned at the Taiwan Photon Source (TPS). Designed to characterize complex beam dynamics and longitudinal filling patterns, the system operates across both the booster and storage rings. By leveraging digital in-phase and quadrature (I/Q) demodulation, the architecture systematically suppresses direct-current (DC) offsets and quadrature phase errors inherent in conventional analog schemes, achieving synchrotron phase extraction and filling pattern measurement at a 3 Hz repetition rate. The resolved BbB data are seamlessly integrated into the accelerator control framework for real-time visualization. This robust digital diagnostic framework provides the necessary precision to investigate transient beam loading and multi-bunch instabilities, establishing a critical tool for advanced beam physics studies in third-generation light sources.

Speaker: Chih-Hsien Huang (National Synchrotron Radiation Research Center)

138 Calibration of the simulation model based on 6-dimensional phase space reconstruction at the PAL-XFEL

The Generative phase space reconstruction (GPSR) method, based on neural networks and differentiable simulations, has been actively investigated to obtain comprehensive information of 6-dimensional phase space of particle beams. At the Pohang Accelerator Laboratory X-ray Free Electron Laser (PAL-XFEL) facility, 6-dimensional phase spaces along the first bunch compressor section were successfully obtained using the GPSR method. Through the successful AI/ML-based beam diagnostics, we plan to optimize the beamline to preserve the beam quality for high-brightness FEL. By using the reconstructed phase space as an input to simulations, we perform optimizations to achieve optimal settings such as quadrupole strengths. Even though we found the optimal condition, it is essential to calibrate the simulation model to accurately represent the real machine. Therefore, we present simulation model calibration based on the reconstructed phase space and experimental datasets with a variety of beamline settings. We further show the uncertainty of the model associated with the measurement. Through this model calibration, we finally present the optimal beamline setting that preserves the beam parameters such as emittances along the undulator section. We expect that the calibrated model can be incorporated into the digital twin frameworks for real-time virtual diagnostics and robust beam optimization for different FEL modes.

Speaker: Seongyeol Kim (Pohang Accelerator Laboratory)

139 Canadian Light Source Machine Toolbox

The Canadian Light Source (CLS) is a third generation 2.9 GeV synchrotron. For many years, the CLS has relied on a version of MATLAB Accelerator Toolbox (AT) which was adopted in 2005 to compute accelerator parameters and beam properties. Since 2022 we have been working to port this functionality into python. This paper will provide an overview of what work has been completed and describe what work is yet to come.

Speaker: Tonia Batten (Canadian Light Source (Canada))

140 Cryogenic beam position monitors production for high luminosity LHC

A total of 32 Beam Position Monitors (BPMs) will be installed in the cryogenic magnet assemblies for the CERN High Luminosity Large Hadron Collider (HL-LHC) project. These BPMs of total 3 types are of challenging mechanical design and built at CERN. The complexity results from the multiple requirements that these BPMs must fulfil, including their operation in a cryogenic environment and their exposure to heat load resulting from the debris of the LHC experimental interactions. Robust design with tight and interlinked mechanical tolerances compatible with the HL-LHC beam induced prerequisites are needed to assure the long-term functionality of these BPMs. This work discusses the requirements of the cryogenic HL-LHC BPMs, including their design, multiple production steps and installation in the cryomagnet assembly.

Speaker: Gerhard Schneider (European Organization for Nuclear Research)

141 Design and optimization of a non-interceptive capacitive pick-up monitor for TOF-based beam energy monitoring at the RFT-30 cyclotron

The RFT-30 cyclotron at the Advanced Radiation Technology Institute (ARTI) of the Korea Atomic Energy Research Institute (KAERI) is a multipurpose proton cyclotron, which is particularly utilized for the production of medical radioisotopes. In radioisotope production, the reaction cross-section, which is strongly dependent on the proton energy and target material, critically influences the production yield. Therefore, precisely monitoring the beam energy during irradiation is considered one of the most important factors.
This presentation introduces the implementation and optimization of a non-destructive capacitive pick-up monitor for the RFT-30 cyclotron, designed to determine the beam energy from the time-of-flight (TOF) of beam bunches. The proposed non-interceptive diagnostic system is expected to enable continuous, real-time TOF-based beam-energy monitoring during irradiation without interrupting routine radioisotope production.

Speaker: Donghyun Kwak (Korea Atomic Energy Research Institute)

142 Design of a high-performance BPM diagnostic system

LCLS-II, the next-generation X-ray free-electron laser at SLAC National Accelerator Laboratory, will employ a continuous-wave 4 GeV superconducting linear accelerator with a nominal bunch spacing of 1 μs to deliver both soft and hard X-ray FEL radiation to experimental users. To meet the stringent beam diagnostics requirements of this facility, the SLAC Technical Innovation Directorate has developed a unified hardware and firmware platform for beam instrumentation based on the Advanced Telecommunications Computing Architecture (ATCA) crate standard. Leveraging this platform, we have designed a beam position monitor (BPM) system incorporating both stripline and cavity BPM pickups, capable of measuring beam position at the full repetition rate of the machine. The system is designed to operate over a wide dynamic range, accommodating bunch charges from 1 pC to 300 pC. This paper presents the design of the BPM electronics, describes the overall system architecture, and reports on performance results obtained during testing on the existing LCLS-II accelerator.

Speaker: Andrew Young (SLAC National Accelerator Laboratory)

143 Design optimization and RF characterization of the SPS-II storage ring BPM prototype

The SPS-II storage ring requires high-precision beam position monitors (BPMs) for orbit control and fast feedback operation. The design employs a button-type BPM with a removable feedthrough flange, allowing independent fabrication, testing, and replacement without disassembling the main vacuum chamber. Following the first prototype, further improvements have been implemented in both mechanical design and signal performance. The main improvement focuses on mechanical tolerance control to ensure precise button positioning with respect to the chamber reference axis. A redesigned flange interface and alignment scheme were developed to reduce eccentricity and angular misalignment, improving geometric symmetry and measurement accuracy. Time domain reflectometry (TDR) measurements of the first prototype showed larger-than-expected reflections. CST Studio Suite was used to perform wake impedance, S-parameter and TDR simulation to intensively investigate impedance discontinuities along the button to connector transition. The feedthrough geometry was optimized to improve impedance matching. This paper presents the mechanical redesign, simulation analysis, and RF measurement results, confirming that the updated BPM design satisfies the SPS-II performance requirements.

Speaker: Porntip Sudmuang (Synchrotron Light Research Institute)

144 Development and performance evaluation of a new BPM data acquisition system for J-PARC MR

J-PARC MR has achieved its initial goal of 750 kW beam delivery and is upgrading equipment toward the next target of 1.3 MW. The Beam Position Monitor (BPM) system comprises 186 sensors and associated data-processing units, and precise determination of accelerator optics is required. We aim to improve Closed Orbit Distortion (COD) and bunch-by-bunch (BxB) position measurements to better than one-third of the current system’s uncertainty, with target precisions of 10 μm for COD and 100 μm for BxB.
To meet these targets, we have developed a new data acquisition (DAQ) system consisting of a front-end attenuator board (ATT), ADC boards, and data storage. The system is scheduled for installation during this summer’s long maintenance period; pre-installation calibration is currently underway. We are considering implementing frequency-dependent calibration and estimating its potential impact on BxB measurement accuracy.
This presentation will report the DAQ design, present the calibration methodology, evaluate the results of DAQ bench tests, and discuss the expected BPM performance.

Speaker: Kenichirou Satou (High Energy Accelerator Research Organization)

145 Development of a BPM system for the ISIS MEBT

The ISIS Neutron and Muon Source, at the Rutherford Appleton Laboratory in the UK, is a pulsed neutron source whose 50 Hz rapid cycling synchrotron accelerates beams of up to 3e13 protons to 800 MeV and delivers them to one of two fixed targets. A Medium Energy Beam Transport (MEBT) will be installed in the ISIS pre-injector after the 202.5 MHz RFQ, to improve transport and injection efficiency, and the MEBT is currently on a test stand. Four button Beam Position Monitors (BPMs) have been installed on the test stand and will be used to optimise transverse position and set-up a series of bunching cavities. Signals from the four pickups on each BPM are mixed to an intermediate frequency (IF) of 10.125 MHz, IQ sampled and processed on an FPGA to measure beam position and phase at each BPM location. In this paper, the physical and electrical characteristics of the BPM system will be summarised, with a detailed description of the front-end electronics.

Speaker: Yusuf Fazlee (Science and Technology Facilities Council)

146 Development of a new BPM system for the HL-LHC Inner Triplets

As part of the upcoming High Luminosity upgrade (HL-LHC), the LHC will be equipped with novel, large aperture Nb3Sn Inner Triplet magnets around the ATLAS and CMS experiments. Each Inner Triplet region will contain 6 new directional coupler Beam Position Monitors (BPMs) to independently measure both LHC beams circulating in a common vacuum chamber. The BPM signals will be measured and processed by a brand-new data acquisition platform based on nearly-direct digitisation using an RF System-on-Chip (RFSoC). This paper discusses the design of the entire system. Results of the laboratory qualification of the new BPMs are shown. The performance of the new data acquisition platform is compared to the one of the systems currently used operationally in the LHC based on laboratory and beam measurements.

Speaker: Chris Hulley (European Organization for Nuclear Research)

147 Development of a novel bunch-by-bunch beam size monitor using silicon strip sensors and the RFSoC architecture

This presentation will discuss the development of a novel bunch-by-bunch beam size monitor (SiXRM) employing silicon strip sensors and an RFSoC-based readout architecture. SiXRM is an ultrafast X-ray beam size monitor developed at the SuperKEKB electron-positron collider, and its development has been ongoing for the past ten years. The existing system uses a 2.7 Gsps ASIC for AD conversion of signals from 42 channels of the silicon strip sensors. During the 2025-2026 SuperKEKB runs, we observed beam-size fluctuations in each bunch during beam collisions, as well as their betatron-tune dependence. The main features of the next-generation SiXRM currently under development are: 1) protecting the digital readout electronics from X-ray exposure by connecting the analog and digital electronics with a differential cable several meters long; 2) the RFSoC integrates fast ADCs, enabling continuous high-speed readout of multiple channels; and 3) a large-scale Zynq FPGA within the RFSoC makes it possible to implement ML-based beam size anomaly detection, thereby enabling early abort of unstable beams. This presentation will focus on these features and discuss the development progress of the next-generation SiXRM.

Speaker: Gaku Mitsuka (High Energy Accelerator Research Organization)

148 Development of a universal broadband synchronous beam signal acquisition daughter board at the SSRF

A universal broadband synchronous beam signal acquisition daughter board has been developed at SSRF. It features four 125 MSPS, 16-bit ADC channels, a low-jitter synchronous clock phase-locked loop (PLL) circuit, a pilot-tone signal generator, and a low-noise power supply circuit. The daughter board is designed to be integrated into the universal FPGA-based data acquisition platform developed by SSRF. By incorporating different RF front-end daughter boards, the system can accommodate a variety of beam measurement applications. This paper presents the design details and reports on the board's application at SSRF.

Speaker: Longwei Lai (Shanghai Advanced Research Institute)

149 Development of an EPICS-based 8-channel 5 GSample/s waveform digitizer and 10 GSample/s function generator for RF System-On-Chip generation 3

In this contribution, we present the development of general purpose 8-channel 5 GSample/s waveform recorder and 10 GSample/s function generator for a 3rd generation AMD Radio Frequency System-On-Chip (RFSoC). The system has an EPICS IOC running on a CPU inside the RFSoC, as well as a direct fiber optic interface to the Swiss Light Source event system. This enables to trigger the data acquisition and waveform synthesis via accelerator events, to synchronize the system with beam injection, pinger magnets, etc. Applications include the monitoring of the attenuated return signals of the SLS multibunch feedback (MBFB) kicker magnets, with the goal to automatically tune the MBFB round-trip delay by temporally overlapping the signal of a single electron bunch and the MBFB kicker response to this bunch. Lab and beam test results will be presented, as well as the benefits of upgrading the present SLS MBFB hardware based on RFSoC generation 1 to generation 3.

Speaker: David Madlener (Paul Scherrer Institute)

150 Development of next-generation universal beam diagnostic electronics platforms at SSRF

At the Shanghai Synchrotron Radiation Facility (SSRF), two next-generation universal beam diagnostic electronics platforms have been developed to meet the diverse beam measurement requirements of the accelerator. The first platform is a digital carrier board based on the Xilinx XCZU19EG, featuring 16-Gbps GTH transceivers and 32-Gbps GTY transceivers. The board provides two FMC HPC connectors and one FMC LPC connector, supporting up to 16 channels of 1-GSPS, 14-bit ADCs and a White Rabbit timing card. It is compatible with various in-house functional daughter boards, enabling flexible adaptation to different application requirements. The second platform is based on the Xilinx XCZU47DR RFSoC, integrating eight 5-GSPS ADC channels and eight 7-GSPS DAC channels. Its high-speed sampling capability enables bunch-by-bunch beam measurement and feedback in the electron storage ring. The board also provides an RF board connector and an FMC LPC connector for the White Rabbit timing card. Both platforms have a wide range of peripherals, including SFP+, Ethernet, DDR4, interlock connectors and GPIOs. These features make the platforms powerful and versatile solutions for beam signal sampling and processing.

Speaker: Longwei Lai (Shanghai Advanced Research Institute)

151 Development of readout software for EPICS-based beam position measurement system of CSNS-II

In the MEBT section of the China Spallation Neutron Source Phase II project, eight strip-type beam position monitor are deployed for precise transverse beam position measurement. The original system employed Bergoz LRBPM electronics modules and NI 1.25 MSPS multifunction data acquisition cards, with upper-layer software developed on the LabVIEW platform to realize orbit measurement functions. The new system described in this paper replaces the NI cards with self-developed 20MSPS high-speed data acquisition cards. The signal readout and processing part is built as a hard IOC based on the EPICS Base framework, completing signal acquisition, real-time processing, and beam orbit data output. Under the standard EPICS IOC architecture, asynchronous mode is utilized to achieve synchronized acquisition of the differential Xout/Yout output signals from the Bergoz LRBPM electronics, while EPICS standard record types are used for data processing and orbit calculation. The system features a clear software hierarchy and stable operational performance.

Speaker: Zhihong Xu (Institute of High Energy Physics)

152 FPGA machine learning for ESS beam diagnostics using Vitis AI DPU and hls4ml on Xilinx Versal board

In collaboration with the European Spallation Source (ESS) and Riga Technical University, we wanted to explore real-time ML model inference on FPGAs for beam waveform classification. To identify a viable solution, we evaluated two ML toolchains on the Xilinx Versal VCK190 adaptive SoC. The first uses the Vitis AI toolchain to integrate the DPUCVDX8G deep learning processing unit and 64-tile AI Engine in the Versal programmable logic. A custom ResNet50 retrained for seven beam waveform classes from the beam position monitor is compiled with Vitis AI framework and deployed at runtime. The second uses the hls4ml framework to convert a CNN-GRU Keras classifier trained on the same seven-class dataset to HLS C++ IP blocks. The model is partitioned into four AXI-Stream blocks to fit synthesis memory, with fixed-point quantization validated against the Keras reference. The Vitis AI toolchain achieved full hardware deployment with measured inference of 2-4 ms. The hls4ml IP blocks fit on the Versal FPGA with synthesis-estimated inference in the tens of microseconds, theoretically outperforming the DPU approach in latency, though demanding greater FPGA resource utilization.

Speaker: Rok Hrovatin (Cosylab)

153 Integrated beam diagnostics and simulation for online proton storage ring tuning at LANSCE

The Beam Position Monitors (BPMs), the primary tuning diagnostics for the Proton Storage Ring (PSR) at the Los Alamos Neutron Science Center (LANSCE), recently underwent an upgrade to their data acquisition system. Whereas the previous system relied on a multiplexed architecture, the new system provides independent readbacks for each BPM and incorporates beam phase measurements. In parallel, the beam current modulation at the beginning of the pulse was transferred from a deflector to a chopper, enabling the delivery of a single pilot minipulse to the PSR on every pulse. This enhancement allows continuous, online monitoring of PSR optics parameters. We present a new tuning software package, RingTune, which integrates multi stream diagnostic data with an online model to provide real time feedback for the Central Control Room and the development environment that simulates the PSR response.

Speaker: En-Chuan Huang (Los Alamos National Laboratory)

154 Laboratory closed-loop testing of the HALF beam current monitor based on high-fidelity beam signal simulator

The beam current monitor for the Hefei Advanced Light Facility (HALF) can acquire the slow, high-precision DC signal from the DCCT and the high-repetition-rate (500 MHz), broadband narrow pulses from a stripline beam position monitor (SBPM) simultaneously. The SBPM was specifically designed for HALF and we deal with the special signals in the time domain. Conventionally, commissioning such processors used up the costly accelerator beam time. To overcome this limitation, we have constructed a laboratory closed-loop test system that replicates realistic beam signals. A programmable current source emulates the DCCT signal, while a custom beam signal simulator built on an FPGA platform generates the SBPM-like wideband pulses with ultra-high sampling rate and high time-domain fidelity. The simulator output closely approximates true beam waveforms, providing a realistic test environment. This work eliminates the reliance on physical beam for the development and validation of beam instrumentation electronics and offers an efficient, repeatable test solution that can significantly reduce machine time occupation.

Speaker: MingDong Ma (University of Science and Technology of China)

155 Measurement of loaded and intrinsic Q-factors of overcoupled SRF cavities operated in SEL mode

We describe a method for measuring the loaded and intrinsic quality factors, the external quality factor, and cavity detuning using algorithms based on solutions of the cavity differential equations in the I/Q domain. We report measurement results for Nb₃Sn cavities at Jefferson Lab’s UITF facility. The measurements include several tens of forward, probe, and reflected signal traces, each several minutes long, recorded at various accelerating gradients and with different klystron amplitude modulation profiles. We evaluated several noise-reduction and Q-factor fitting methods, achieving good accuracy for loaded and external Q values and satisfactory accuracy for Q₀.

Speaker: Sergey Kuzikov (Thomas Jefferson National Accelerator Facility)

156 Non-invasive determination of scaling and skew factors for X-ray beam position monitors

X-ray beam position monitors (XBPMs) are an indispensable tool for determining the position of the white beam in beamline front-ends at synchrotron light sources. White beam XBPMs at Diamond Light Source typically use four tungsten blades which intercept the tails of the transverse beam profile in order to not disrupt user beam. The measured currents from the four blades are converted to a beam position using the difference-over-sum calculation and a scaling factor. This scaling factor is dependent on the transverse profile of the X-ray beam, and thus reliant on the gap of the insertion device providing the X-rays to the front-end. A method for determining the scaling factor using correlation of the intrinsic electron beam position monitor (EBPM) noise with XBPM measurements has been presented previously. This approach introduces error when there is a rotation of the XBPM measurements with respect to the EBPM measurements. In order to resolve this, an affine transformation between the EBPM and XBPM measurements has been tested, and the scaling factors extracted. The affine transformation can also be used to calculate rotation or skew factors. Measurements of these scaling and skew factors are presented along with interpretations.

Speaker: Claire Houghton (Diamond Light Source)

157 Operational experience with the RF-SoC for the HL-LHC BPM system

The High-Luminosity upgrade of the LHC requires new
Beam Position Monitor (BPM) Data Acquisition Electronics
capable of improved resolution and robustness. The new sys-
tem is based on a Xilinx RF System-on-Chip, which digitises
the eight BPM signals using integrated high-speed ADCs.
During testing at the end of 2025, significant perturbations
were observed in the system’s orbit measurements after the
first injection of each fill. Subsequent tests revealed that the
cause was the internal background calibration mechanism
of the ADC, which aims to compensate for drifts due to
temperature of the gain, offset and time skew of the internal
sub-ADCs. This paper presents the investigation into the
cause of the perturbations, evaluates candidate mitigation
strategies, and validates the chosen approach with beam data
from the 2026 LHC run.

Speaker: Chris Hulley (European Organization for Nuclear Research)

158 Optimization of ALBA II BPM pickups

As ALBA II is currently under development, the machine design has undergone several updates. Some of these modifications directly impact the Beam Position Monitor (BPM) pickup response. Specifically, the transition of the vacuum chamber cross-section from circular to rhomboidal brings the pickup electrodes closer to the beam, increasing the wakefield effects and potential parasitic heating. An improved design, validated through simulation, is presented in these proceedings. Furthermore, the integration of these pickups into the copper vacuum chamber introduces material compatibility challenges; in particular, the use of Kovar in these assemblies will be discussed.

Speaker: Laura Torino (ALBA Synchrotron (Spain))

159 Optimized beam position monitor for the RFT-30 cyclotron

The RFT-30 cyclotron at the Advanced Radiation Technology Institute (ARTI) of the Korea Atomic Energy Research Institute (KAERI) is a multipurpose proton cyclotron that delivers proton beams of up to 30 MeV for medical radioisotope production and the neutron applications. In the beam transport line, reliable information on the transverse beam position is essential for stable beam delivery and efficient beam tuning. A misaligned beam can collide with the beam pipe or nearby accelerator components, resulting in beam loss, unwanted activation, and potential hardware damage. Therefore, real-time beam-position diagnostics are required for the straight beamline section of the RFT-30 cyclotron.
This presentation introduces the design and optimization of a beam position monitor (BPM) specific to the beam conditions and beamline geometry of the RFT-30 cyclotron. The design process considered key parameters such as proton energy, beam current, beam pipe geometry, and bunch length. The electrode configuration and arrangement were investigated to enhance position sensitivity and signal response under the expected operating conditions. The proposed BPM is expected to provide real-time transverse beam-position information and contribute to stable beam tuning and operation of the RFT-30 cyclotron beamline.

Speaker: Donghyun Kwak (Korea Atomic Energy Research Institute)

160 Performance improvement of the XBPM2 in the TPS front end

Two sets of blade-type X-ray beam position monitors (XBPMs) are installed in the front end of Taiwan Photon Source (TPS), with the downstream monitor designated as XBPM2. Significant challenges in the calibration and operation of XBPM2 in the TPS front end have been primarily attributed to the upstream mask aperture size being nearly identical to the blade tip spacing. It leads to a restricted effective horizontal linear region and results in discrepancies between Kx and Ky, thereby increasing horizontal measurement error. By enlarging the upstream mask aperture, a significant improvement in the performance of XBPM2 was observed, and the detailed results will be presented in this paper.

Speaker: Chia-Mu Cheng (National Synchrotron Radiation Research Center)

161 Performance testing of DBPM for the HALF storage ring

The Hefei Advanced Light Source (HALF) is a fourth-generation diffraction-limited storage ring under construction in China, imposing stringent requirements on its beam position monitor (BPM) system for sub-micron resolution, low-latency fast orbit feedback, and robust long-term stability. This paper presents the comprehensive performance testing of all DBPM developed for the HALF storage ring. The test campaign evaluated each processor in three parallel acquisition modes: turn-by-turn (TBT) at 624.75 kHz, fast acquisition (FA) at 20 kHz and slow acquisition (SA) at 10 Hz. A simulated beam signal testbed based on an RF signal source was constructed, enabling reproducible and automated batch testing. DBPM also underwent temperature drift characterization within 10~40 ℃, as well as beam current dependence evaluation covering 1–400 mA. The test results show that all DBPMs meet the technical specifications, and the statistical distributions demonstrate high consistency, satisfying the requirements of the HALF project.

Speaker: MingDong Ma (University of Science and Technology of China)

162 Phase calibration of signal cables for TOF measurement at KOMAC 100 MeV proton accelerator

The Korea Multi-purpose Accelerator Complex (KOMAC) operates a linear proton accelerator consisting of an ion source, a Low Energy Beam Transport (LEBT), a Radio Frequency Quadrupole (RFQ), and two Drift Tube Linac (DTL) sections. The beam is extracted at 50 keV and accelerated to 3 MeV through the RFQ, subsequently reaching 20 MeV in DTL Section 1 and a final energy of 102.6 MeV in DTL Section 2. DTL Section 2 comprises seven individual tanks, each followed by a Beam Position Monitor (BPM) to monitor beam parameters.

To implement accurate online beam Time-of-Flight (TOF) measurements using these BPMs, precise knowledge of the phase offset for each signal cable is essential. However, environmental factors have introduced unknown phase shifts, limiting the accuracy of real-time energy monitoring. In this study, we performed a phase calibration of the BPM signal cables across the DTL Section 2. This paper summarizes the calibration methodology employed, the measured phase offset values for each BPM, and the resulting improvements in TOF measurement precision.

Speaker: Seok Ho Moon (Korea Multi-purpose Accelerator Complex)

163 Precise trigger and bunch ID distribution for SHINE beam data synchronization

The Shanghai High Repetition Rate XFEL and Extreme Light Facility (SHINE) is a high repetition rate X-ray free-electron laser facility currently under construction in Shanghai, China. Beam data synchronization plays a vital role in beam parameter analysis, performance optimization and fault diagnosis. Based on White Rabbit technology, a timing system is established to distribute synchronous trigger signals and unique bunch IDs to various beam diagnostic electronics. It covers the measurements of beam position, beam loss, beam length, beam arrival time and other relevant parameters. The system enables long-distance precise timing signal distribution over a span of 3.1 km, with the RMS jitter of trigger signals lower than 10 picoseconds. The system design scheme and experimental test results are presented in this paper.

Speaker: Yingbing Yan (Shanghai Synchrotron Radiation Facility)

164 Preliminary design of the digital signal processing scheme for the CSNS-II RCS BPM electronics

The CSNS-II upgrade aims to further increase the RCS beam power from the presently achieved level of about 185 kW to 500 kW. Under the higher beam power, the RCS BPM electronics will face challenges due to the increased input signal voltage and the requirement for a larger dynamic range. To achieve both a wide dynamic range and high position resolution, a new BPM electronics system is being designed. For the digital signal processing, different position calculation methods were compared, including the integral method, RSS and the standard deviation method. The results indicate that, in our case, an ADC resolution higher than 14 bits is required when noise is taken into account. In addition, the standard deviation method shows better immunity to DC noise. Based on these results, a preliminary digital signal processing scheme was designed.

Speaker: Chunjie Xie (Institute of High Energy Physics)

165 Radiation hardness test of a silica aerogel cherenkov radiator for a muon beam profile monitor for the J-PARC muon g-2/EDM experiment

A muon linear accelerator accelerating muons up to 212 MeV is being developed for the J-PARC muon g-2/EDM experiment. The beam intensity is estimated at only a few tens of muons per pulse, and the required transverse emittance is 1.5 π mm·mrad or less. The beam radius is expected to be σ ~ 1 mm, requiring a resolution of about 0.1 mm to resolve it. We are developing beam profile monitors at 40 MeV and 212 MeV satisfying this resolution. Conventional monitors are difficult to apply, since dark current electrons accompanying the beam make accurate measurement challenging. We exploit the difference in Cherenkov angle between muons and electrons to extract the muon signal alone; at 212 MeV, a silica aerogel is used as the Cherenkov medium.
Since the aerogel is irradiated by the beam during operation, its radiation hardness must be evaluated. Radiation-induced changes in refractive index alter the focal length of the optical system, affecting spatial resolution.
We irradiated the aerogel samples with electron beams under different conditions and measured transmittance and refractive index before and after irradiation, and report the results, discussing the feasibility of the monitor.

Speaker: Risa Nakagawa (The Graduate University for Advanced Studies, SOKENDAI)

166 Real-time prediction of multi-turn beam dynamics using ML surrogates for the proton storage ring at LANSCE

While basic beam parameters can be determined quickly using an optics model for the Proton Storage Ring (PSR) at LANSCE, some parameters, like effective beam current, beam sizes, and the impacts of RF bunchers, normally require multi-turn beam dynamics simulations that are often too long for the control room. In this effort, we present an ML surrogates based on PyORBIT simulations of the PSR to allow real-time feedback for parameters requiring 1715-turn simulations as well as an improvement to the optics parameters We further demonstrate an AI-assisted workflow that streamlines Monte Carlo simulation generation, post-processing, data analysis, model building, and training, enabling rapid iteration of surrogate models. This rapid prototyping capability, combined with fast surrogate inference, enables a model-based diagnosis for real-time operational decision-making in the CCR.

Speaker: En-Chuan Huang (Los Alamos National Laboratory)

167 Recent beam characterization and performance baseline of the Siam Photon Source injector

As part of an ongoing performance improvement at the Siam Photon Source (SPS), the 40 MeV electron injector system is undergoing an evaluation of its present beam properties. While previous measurements reported an overall transmission efficiency of approximately 26 % through the injector linac and Low-Energy Beam Transport line (LBT), recent investigations were conducted to evaluate the current machine status and investigate the origins of residual beam losses. To identify the mechanisms limiting transmission efficiency, transverse beam characteristics were evaluated using phosphor screen monitors with dipole and quadrupole scan techniques. Image processing routines with region-of-interest bounding and Kernel Density Estimation (KDE) were implemented to extract beam profiles from the screen data. The diagnostic analysis showed a relative energy spread of 3.2 %, which causes the transverse beam envelope to expand and approach the physical aperture limits within the LBT, alongside geometric transverse emittances of $\varepsilon_x = 6.2$ mm$\cdot$mrad and $\varepsilon_y = 1.9$ mm $\cdot$mrad. These measurements identify the root cause of the beam losses and provide critical data for beam dynamics simulations and machine optimizations.

Speaker: Thakonwat Chanwattana (Synchrotron Light Research Institute)

168 RFSoC based stripline BPM readout hardware for use at SuperKEKB's injection points

At the SuperKEKB storage rings, a special stripline BPM is used at the injection points to measure the injection beam arriving from the beam transport line after it traverses all septum magnets, just before entering the storage rings. A new readout device based on the RFSoC platform and tailored to this application has been developed, successfully deployed and continuously operated during SuperKEKB operations since November 2025. The main motivation for this development was the clean, independent measurement of both 96 ns spaced bunches in the so called two-bunch injection mode, where two bunches are injected in one injection cycle. A secondary objective was, however, to also collect experience with the RFSoC platform towards future in-house developments at KEK. This presentation will summarize the important aspects of the development and evaluation of the developed device, the details of which are described in our previous publication, as well as report on the recent operations and future plans and considerations towards possible deployment to further locations at the beam transport line where performance of the present readout devices is poor.

Speaker: Bela Urbschat (Nagoya University)

169 Sensitivity of button- and stripline beam position monitors to crabbing angle and trajectory tilt angle

Crab crossing is used in the High-Luminosity LHC (HL-LHC) to increase luminosity. Button- and stripline beam position monitors (BPMs) are used to observe the beam crabbing and to use the signal for RF noise feedback. The BPMs are not only sensitive to the crabbing angle, but also the trajectory tilt and center-of-mass position. Untangling the individual contributions demands attention and potentially limits the crabbing angle measurement. The output signals of button- and stripline BPMs due to the crabbing angle and trajectory tilt angle are individually investigated with electromagnetic particle-in-cell simulations and compared to analytical approximations. The limits on the crabbing signal measurement in the presence of a trajectory tilt angle are discussed.

Speaker: Daniel Sittard (European Organization for Nuclear Research, Karlsruhe Institute of Technology)

170 Synchrotron beam position monitors performance with Libera Hadron system in CNAO facility

CNAO in Pavia is one of the first centers for hadrontherapy in Europe, treating patients since 2011. The center represents an international reference for machines specifically designed for this purpose. The synchrotron BPM electronics currently relies on analog boards that compute the ratio between difference and sum signals from the shoebox pickup, with signals subsequently acquired by digital cards. Although the system operates reliably, it provides beam position measurements at a rate of only 1 kHz, while the revolution frequency ranges from 0.5 to 3 MHz. Libera Hadron, developed by Instrumentation Technologies, is a well-established and widely proven instrument, extensively used in large accelerator facilities as well as in several smaller installations. The system is capable of acquiring pickup signals with 250 MSps ADCs and performing advanced beam diagnostics, including bunch-by-bunch and averaged position measurements, as well as FFT-based analysis for tune determination. A Libera Hadron unit was tested at CNAO, where turn-by-turn beam position data were analyzed at different energies and intensities using proton, helium, and carbon ion beams. This paper presents the results obtained with the Libera Hadron system.

Speaker: Manuel Cargnelutti (Instrumentation Technologies (Slovenia))

171 The importance of software in data acquisition: a Canadian Light Source example

At the beginning of my master’s thesis, the software used for acquiring images of the electron beam was BeamGage Professional, a paid software that came with the cameras. This software was prone to issues and would commonly crash or fail to connect to the camera. The solution to this problem was often to power cycle the camera, which involved turning off RF systems, breaking lockup, and accessing the accelerator section. Eventually FlyCapture2, a free-to-use software, was suggested by the software group. FlyCapture2 was used for the remainder of the image acquisition for my thesis. This work will go over the unexpected differences found between the two software packages, and how it gave the Canadian Light Source the confidence to transition away from BeamGage for good.

Speaker: Chelsea-Lea Randall (Canadian Light Source (Canada))

172 The new upgraded beam profile monitoring system of the CERN IRRAD proton irradiation facility for post LS3

The beam quality is of utmost importance in the operation of the IRRAD proton irradiation facility at CERN. During irradiation, the intensity, the transverse and longitudinal beam profiles are monitored online with custom-made Beam Profile Monitor (IRRAD-BPM) devices. The BPM sensors were developed and recently significantly improved thanks to a new manufacturing technology based on microfabrication of metal nano-layers. To be able to exploit all features of these new devices, the readout DAQ technology, as well as the handling and display of the BPM data, also needed to be substantially improved. The existing DAQ technology employed for the readout needed to be upgraded to cope with increasing sensitivity (nA range) and timing performance (sampling rate down to the ms range). Moreover, the display and analysis of the BPM data can also be substantially improved with the innovative idea of applying Machine Learning (ML) techniques. A first prototype of an ML model, aiming to perform the automatic pattern recognition or anomaly detection of beam profiles, was thus developed and tested. The first prototype of this full new system is currently being tested during the irradiation run 2026 of IRRAD with the goal to replace the former system after the CERN Long Shutdown 3 (LS3). In this work we present the design and the architecture of the new IRRAD-BPM system (featuring upgraded sensors, DAQ unit and data handling capabilities), and the latest results on its performance with beam.

Speaker: Federico Ravotti (European Organization for Nuclear Research)

173 Turn-by-turn tune analysis using adaptive BPM ensembles in the Fermilab Mu2e delivery ring

The Mu2e experiment at Fermilab requires stable resonant slow extraction from the Delivery Ring, making reliable tune monitoring an important operational diagnostic. This work investigates BPM-based tune-candidate extraction using synchronized turn-by-turn position data distributed across multiple digitizers. Each spill contains approximately 50,000 turns from many BPMs in both transverse planes, enabling spectral analysis of tune-like structure.

The analysis captures coherent spill snapshots, verifies synchronization using stream timestamps, and computes tune candidates in configurable horizontal and vertical tune bands. Rather than relying on a single BPM or fixed BPM list, it evaluates BPM quality on a spill-by-spill basis and selects small adaptive BPM ensembles.

A multi-spill study shows that tune observability is distributed and dynamic rather than concentrated in one globally optimal BPM. Adaptive ensembles improve tune-candidate quality compared with single-BPM selections, with the clearest results in the vertical plane. The horizontal plane shows useful ranking structure but weaker visibility under present thresholds.

Direct evaluation of fixed global BPM sets shows that static selections do not reproduce dynamic per-spill performance. These results motivate an adaptive BPM-ensemble approach for Delivery Ring tune analysis using selected BPM subsets, confidence metrics, and quality flags rather than a single preferred BPM or fixed BPM list.

Speaker: Derek Steinkamp (Fermi National Accelerator Laboratory)

174 Unsupervised deep learning framework for longitudinal bunch-by-bunch phase diagnostics and status monitoring at HLS-II

Real-time bunch-by-bunch diagnostics are essential for stable synchrotron operation under top-off conditions. Conventional monitoring based on individual observables struggles to characterize complex beam dynamics from multi-parameter coupling. To address this, an unsupervised deep-learning framework was developed for automatic longitudinal bunch-by-bunch phase diagnostics and machine parameter monitoring at the Hefei Light Source II (HLS-II). The framework utilizes high-precision steady-state bunch phase measurements through two complementary data-driven branches. An autoencoder (AE) branch with dimensionality reduction and ensemble clustering characterizes the global structure of machine operating states. In parallel, an LSTM-VAE branch captures temporal correlations in longitudinal oscillation signals, enabling localized anomaly detection via multi-scale reconstruction error analysis and an Isolation Forest. Applied to HLS-II operational data, the framework successfully identified a significant longitudinal anomaly on September 18, 2025. Correlation with historical machine parameters revealed that the event was driven by large phase fluctuations in the higher-harmonic cavity, which modified the longitudinal potential well and altered the synchrotron frequency. The results demonstrate that the proposed method effectively identifies latent parameter anomalies and their underlying physical origins without labeled data, providing a practical tool for online beam diagnostics.

Speaker: Xinru Gao (University of Science and Technology of China)

175 Usage of Red Pitaya single board DAQ system in COSY beam instrumentation

The Red Pitaya is a versatile single-board DAQ System equipped with two 125 MHz ADCs and DACs each, 16 DIOs, and four slow ADCs and DACs each. For signal processing, a Xilinx Zynq including a dual-core ARM Cortex and FPGA fabric is present. This low-cost board was used in several beam instrumentation devices at the COSY proton synchrotron, including the BLM system or for current measurements at a beamline. The applications at COSY and the integration within the EPICS control system are presented and, as well, the benefits and disadvantages of the setup are discussed.

Speaker: Christian Boehme (Forschungszentrum Jülich)

176 X-ray beam intensity monitoring for CBXFEL cavity alignment and commissioning

The Cavity-Based X-ray Free-Electron Laser (CBXFEL) project in the Linac Coherent Light Source (LCLS) Hard X-ray (HXR) undulator line requires X-ray beam diagnostics for alignment and optimization of the optical cavity. The instrumentation combines silicon and diamond X-ray Beam Intensity Monitors (XBIMs), direct and amplified signal paths, high-speed digitizers, accelerator timing, and EPICS-based controls. The system acquires beam-synchronous XBIM signals at up to \qty{120}{Hz} and associates each measurement with the corresponding accelerator pulse. This paper describes the system architecture and commissioning results, including crystal alignment, intra-cavity intensity measurements, cavity ringdown, and investigations of detector grounding, signal conditioning, and electrical noise.

Speaker: An Le (SLAC National Accelerator Laboratory)

19:00 Pre-dinner Reception

19:30 Conference Dinner

Dinner will be held at the Whistler Conference Centre, Grand Foyer

Thursday 3 September

Overview and Commissioning

Convener: Volker Schlott (Paul Scherrer Institute)

177 Experience with heavy ion beam instrumentation during HIAF beam commissioning

The High-Intensity heavy-ion Accelerator Facility (HIAF) is a proton and ion accelerator facility, coupling a superconducting linac (iLinac) with a synchrotron to produce intense stable and radioactive beams with energies ranging from MeV/u to GeV/u. The official construction began on December 23, 2018, with the entire beam commissioning phase launched on October 27, 2025. Within 30 hours, the 18O6+ beam was accumulated, accelerated to 2.6 GeV/u with a fast ramping rate of 12 T/s inside the BRing, and then transferred and stored in the SRing successfully. Following a month of iLinac optimization, two high-intensity beams were then commissioned and tested in December: 18O6+ at 2.6 GeV/u with 2.5E11 particles per pulse (ppp) extracted from BRing and 209Bi31+ at 851 MeV/u exceeding 3.0E10 ppp. Those results confirms that the facility’s performance has surpassed its design specifications. The day-one experiment was started by the end of 2025. A diverse suite of instrumentation systems played a crucial role during the extremely fast beam commissioning, enabled the matching of different accelerator sections with high transmission rates, helped to achieve efficient acceleration and high intensity with low beam loss. In this paper, we present the initial beam measurements, as well as lessons learned from the experience.

Speaker: Hong Ming Xie (Institute of Modern Physics, Chinese Academy of Sciences)

178 Overview and status of beam diagnostics development for the CSNS upgrade project

The China Spallation Neutron Source (CSNS) is a major facility for neutron science in China, currently operating at an average beam power of 170 kW, with a beam energy of 1.6 GeV and a repetition rate of 25 Hz. In 2024, the CSNS Upgrade Project (CSNS-II) was launched, introducing new instrumentation for the superconducting linac, RCS, and additional beamlines. In 2025, we have upgraded the instrumentations in the RCS injection area featured with the SEM grids with d100μm CNT fibers, and a rectangular linear-cut BPM. This presentation provides an overview of the new diagnostics systems and their associated challenges, such as the non-intercept beam profile monitors at the superconducting linac and RCS, the wide-dynamic range BPM system for the RCS, and the beam-loss monitors for the fast machine protection system. It also reviews recent R&D efforts on advanced technologies, including laser-wire monitors, ionization profile monitors, fast Faraday cup/EO modulation, RCS BPM electronics, and innovative materials such as carbon nanotube (CNT) wires, fluorescent wires, and anti-resonance hollow core fibers.

Speaker: Renjun Yang (Institute of High Energy Physics)

179 Optical imaging–based beam instrumentation for high-power accelerator commissioning and operation at the spallation neutron source

The recently completed Proton Power Upgrade (PPU) project at the Spallation Neutron Source (SNS) doubled the accelerator’s design capability from 1.4 to 2.8 MW by increasing the beam energy from 1.0 to 1.3 GeV and the beam current from 26 to 38 mA. Following multiple installation phases and extensive beam commissioning, SNS achieved reliable operation at 1.9 MW on target at 1.3 GeV in late 2025. Throughout this process, optical imaging–based beam instrumentation played a critical role in machine commissioning, tuning, and high-power operation. This paper reports commissioning results from several key optical diagnostic systems deployed during the PPU, including the stripper foil temperature monitoring system, ring injection dump imaging system, electron catcher imaging system, and target imaging system.

Speaker: Abdurahim Oguz (Oak Ridge National Laboratory)

10:20 Break

Invited Oral

180 An alchemist's dream - turning lead to gold

Radioisotope production and radioactive ion beam facilities are essential tools for advancing research in nuclear physics and enabling applications in medicine, materials science, and other fields. This talk provides an overview of the Advanced Rare Isotope Laboratory (ARIEL), the next expansion of TRIUMF’s isotope production and radioactive ion beam capabilities.  Following TRIUMF’s 2026 long shutdown, ARIEL will have completed its major construction phase and entered commissioning. The facility will triple TRIUMF's radioactive ion beam (RIB) availability and will include the world’s highest-power photofission RIB production facility. The presentation will describe ARIEL’s capabilities and scientific reach, review the facility’s construction status, and outline plans for commissioning and early operations.

Speaker: Luca Egoriti (TRIUMF)

Opening, Closing, Special Remarks: Closing

Convener: Marco Marchetto (TRIUMF)