Choose timezone
Your profile timezone:
13th Diagnostics Experts of European Light Sources (DEELS)
→
Europe/Zurich
Paul Scherrer Institute
Paul Scherrer Institute
PSI CH, PSI, Forschungsstrasse 111, 5232 Villigen,
Description
The Paul Scherrer Institute, Center for Accelerator Science and Engineering, is pleased to host the 13th Diagnostics Experts of European Light Sources (DEELS) workshop.
The goal of the workshop is to bring together the diagnostics community to discuss common challenges, share recent developments, and strengthen collaboration among different facilities.
As is customary for DEELS, we expect that all participating institutes will contribute to the scientific program.
We look forward to an engaging and productive exchange among all participants.
Information on the Instrumentation Technologies Libera Workshop can be found here.
Please note:
-
DEELS 2026 will be an in-person event. Remote participation will not be available.
-
There is no registration fee. Accommodation and transportation costs must be covered by each participant's home institute.
Contact Persons
Participants
-
-
08:30
Registration
-
Session: 1Convener: Cigdem Özkan Loch (PSI - Paul Scherrer Institut)
-
1
WelcomeSpeaker: Cigdem Özkan Loch (PSI - Paul Scherrer Institut)
-
2
The SLS 2.0 Booster-to-Ring Transfer Line - Design Criteria, Diagnostics Layout and Beam Results
Due to the limited transverse acceptance of fourth generation light sources, the characterization and control of the incoming beam from the booster to the storage ring is an important asset to achieve highly efficient and reproducible injection.
For the up graded Swiss Light Source (SLS 2.0) storage ring, a new booster to ring transfer line (BRTL) has been designed with a non dispersive section for beam parameter measurements and a double BPM corrector configuration for position and angle feedback of the injected beam.
Based on the BRTL design criteria, first beam results during SLS 2.0 commissioning are presented, including experience with quadrupole scans to document emittance exchange at the end of the booster ramp and steering stabilization of the beam at the injection point, resulting in a stepwise optimization of transmission into the storage ring.
Speaker: Volker Schlott (PSI - Paul Scherrer Institut) -
3
Overview of SLS 2.0 CommissioningSpeaker: Felix Armborst (PSI - Paul Scherrer Institut)
-
4
Commissioning of SLS 2.0 BPM and Fast Orbit Feedback System
In this contribution, we present the commissioning results and experience of the SLS 2.0 RF BPM and fast orbit feedback BPM system. This includes an analysis of the orbit stability in the storage ring.
Speaker: Boris Keil (PSI - Paul Scherrer Institut) -
5
SLS 2.0 MPS Commissioning and First Operation Experience
As SLS 2.0 transitions from machine commissioning to full beamline commissioning and user operation, the demands on long-term reliability and high availability of the accelerator complex increase significantly. Ensuring minimal downtime requires fault-handling mechanisms that are both rapid and systematic, enabling the machine to respond safely and consistently to unexpected conditions. This discussion will examine the architectural principles, integration strategy, and operational experience of the key machine‑protection systems. For SLS 2.0. these systems include the beam dump controller, the machine interlock system, the post‑mortem framework, the injection guard, and the controlled emergency beam‑dump procedure. Together, they form a coordinated protection layer essential for safeguarding equipment, maintaining beam quality, and supporting reliable user operation. The session aims to explore lessons learned, remaining challenges, and opportunities for further optimization as SLS 2.0 enters routine operation.
Speaker: Felix Armborst (PSI - Paul Scherrer Institut)
-
1
-
10:40
COFFEE
-
Session: 2Convener: Guenther Rehm (Helmholtz-Zentrum Berlin)
-
6
Proposed Transition to CW Mode at the Eu-XFEL: Implications for Beam Diagnostics
The European X-ray Free-Electron Laser (Eu-XFEL) currently operates in a pulsed mode, delivering ultra-short, high-intensity X-ray pulses for a wide range of scientific applications. However, transitioning to a continuous-wave (CW) operation mode could significantly enhance its capabilities by enabling higher average brightness, improved temporal coherence, and novel experimental opportunities. This contribution addresses the critical modifications required in the electron beam diagnostics system to accommodate the transition from pulsed to CW operation.
Key challenges include the need for real-time, high-resolution monitoring of beam parameters under continuous conditions, such as beam position, energy spread, emittance, and charge stability. Existing diagnostic tools, optimized for pulsed operation, may face limitations in bandwidth and sensitivity. We propose adaptations such as the integration of high-speed, low-noise detectors and advanced signal processing techniques.
This work outlines a roadmap for upgrading the Eu-XFEL’s electron beam diagnostics infrastructure, ensuring compatibility with CW operation while preserving the facility’s cutting-edge performance for next-generation X-ray science.Speaker: Dirk Lipka (DESY) -
7
Digital Platform Reusability for Elettra 2.0 Systems
An FPGA-based platform has been developed in-house for the Electron Beam Position Monitor (eBPM) systems of Elettra 2.0, the ongoing upgrade of the Italian synchrotron toward a higher brilliance lightsource. Leveraging its modularity and high processing capabilities, this platform has been extended to various subsystems, including the Digital Low-Level Radio Frequency (DLLRF).
To maximize firmware and software reuse, a scaled-down version utilizing a lower-density FPGA was developed for less resource-intensive applications, such as Beam Loss Monitors (BLM) and Fast Beam Dump systems.
This paper discusses the advantages of this standardized framework, highlighting not only the increased development efficiency but also the benefits of a unified architecture. This approach enables the delivery of synchronous turn-by-turn data across all integrated units via a coherent data ecosystem, which then interfaces with the DPDK-based (Data Plane Development Kit) control layer.
Speaker: Gabriele Brajnik (Elettra-Sincrotrone Trieste Scpa) -
8
Libera Digit 500 as a precise averaged bunch-by-bunch charge readout at ESRF
The Libera Digit 500 at the ESRF is equipped with firmware that does a real-time internal summing-up at Turn-by-Turn rate (355KHz)
on the charge of each of the individual bunches (992 for SR , 352 for SY), effectively providing averaged data in bunch-by-bunch domain. (bunch period is 2.8nsec, RF-frequency 352MHz)
This allows very precise measurements of the evolution of these bunch charges over an acquisition duration of typically 1 second.
i.e. this summing-up reduces the noise by roughly a factor 600 w.r.t. to single shot noise.
Results obtained with tests on the beam show that e.g. a tiny loss on one bunch of the order 1E-4 can be clearly detected.
This technique works both during injection and the slow decay of the stored beam.
The inconveniences of e.g. the precise & strong dependence of the phase & synchronization of the device w.r.t. the beam phase will also be mentioned, e.g. the above technique works only well for filling-patterns with a stable beam phase over time.Speaker: Simon Mattiazzi (Instrumentation Technologies) -
9
Zynq FPGA processing signal system for SOLARIS storage ring diagnostics.
After the successful testing of the BBQ system for passive tune measurements using direct diode detectors at the SOLARIS storage ring, the next step - and a significant challenge - was the proper acquisition and processing of the analog signal. To address this, a 24-bit ADC system integrated with a Zynq FPGA was developed to ensure high-quality signal acquisition and reliable data processing.
In addition, based on the developed hardware platform, a dedicated BPM signal spectrum analyzer is currently being designed, with the ultimate goal of replacing the device presently in use.
The presentation will summarize the progress achieved to date, planned improvements, technical challenges encountered, and the expected final performance parameters of the system.Speakers: Mateusz Szczepaniak (NSRC SOLARIS), Mr Michal Zurek (NSRC SOLARIS) -
10
Data Timestamping for Fast Data Acquisition (sniffer archiver)
In the context of the new BPM readout electronics deployment on the machine, the fast data capture (Diamon Sniffer Archiver) is becoming obsolete and will be replaced with enhanced capability for Soleil II :
- the storage of any types of data: BPM, PSC (instructions and/or re-read values), LLRF (?)
- coming from different equipments,
- for several days (currently 2 weeks)Main purposes of this "fast archiver" is to:
- investigate in case of problems: search for repetitive patterns
- perform measurements to identify the machine (fast matrix, BBA, etc.)
- perform analyses to understand the machineTwo architectures are currently evaluated in term of performance at Soleil. But there is still an open question :
which time source should be used to timestamp the data ?
Granularity issue, synchronisation, strategy, philosophy... Let's discuss!Speaker: Aude Grabas (Synchrotron Soleil)
-
6
-
13:00
LUNCH @OASE & COFFEE @TIME OUT
-
Session: 3Convener: Laura Torino (ALBA-CELLS)
-
11
Electron bunch length measurement at ESRF-EBS using Time Correlated Single Photon Counting
The commonly used bunch length diagnostics in electron storage rings is the streak camera, fed by visible synchrotron light. Although this instrument is able to precisely measure the shape of very short longitudinal profiles of idividual bunches, it also has a major disadvantage: its photocathode is subject to aging upon permanent exposure to incoming light. It is therefore mainly used for dedicated beam studies under controlled conditions.
Time correlated single photon counting (TCSPC) is already used in synchrotron light sources to precisely measure the filling pattern and bunch purity. Modern fast single photon counting detectors and TCSPC electronics open the way to apply this technique to resolve the bunch lengths of stored electron beams.
We present our first results of bunch length measurements using TCSPC at the ESRF.Speaker: Friederike Ewald (ESRF) -
12
Filamentation due to the Vacuum-to-Air Window of the X-ray Pinhole Camera
X-ray pinhole cameras are still the preferred option for emittance measurement in synchrotron light sources due to their simplicity in design, operation and data analysis. It has been observed over many years at multiple facilities, that a structure similar to a diffraction pattern is observed when the electron beam size is squeezed. This effect is called filamentation and has been identified to come from the vacuum-to-air window of the pinhole camera. It is problematic due to its interference with beam size measurements, particularly when operating close to the resolution limit of the pinhole camera. Given that the brilliance and coherence will increase in 4th generation synchrotrons, such as Diamond-II, from the reduction in beam emittance, it is important we minimise this filamentation effect to ensure accurate beam size measurements are available. Here we report on recent measurements in preparation for Diamond-II.
Speaker: Lorraine Bobb (Diamond Light Source)
-
11
-
15:20
SLS 2.0 Tour
-
18:00
DINNER
-
08:30
-
-
Session: 4Convener: Friederike Ewald (ESRF)
-
13
Calculation of BPM electrical centers using BpmLab and CST
We present a comparison of BPM electrical center calculations using the 2D electrostatic solver BpmLab and full 3D simulations in CST.
While BpmLab accurately reproduces electrostatic potentials for 2D geometries, it cannot capture the 3D field distortions introduced by realistic BPM button structures. As a result, discrepancies arise between 2D and 3D models, and in the presence of button displacements, 2D models systematically underestimate electrical offsets.
These results demonstrate that reliable prediction of BPM electrical centers in the presence of mechanical imperfections requires full 3D modeling
Speaker: Dirk Lipka (DESY) -
14
Using a Button BPM at 3GHz
This talk illustrates an attempt to use an installed BPM pickup to detect signals at 3 GHz.
Speaker: Guenther Rehm (Helmholtz-Zentrum Berlin) -
15
Electromagnetic characterization of the first 16 pickup prototypes for the Elettra 2.0 BPMs
A total of 916 button type beam position monitor (BPM) pickups have been foreseen to meet the requirements of the Elettra 2.0 light source.
The first 16 prototype units, intended to validate the complete set of mechanical, vacuum, and electromagnetic characteristics, have been fully evaluated and successfully
qualified through Factory Acceptance Tests (FAT) and Site Acceptance Tests (SAT).
After a brief overview of the pickup design rationale, this contribution presents the results obtained from the electromagnetic characterization of each pickup sample,
performed using two types of RF test fixtures. The first test fixture operates up to 16 GHz, while the second one extends the measurement range up to 40 GHz.
Final considerations focus on the comparison between measured data and electromagnetic simulations.Speaker: stefano cleva (Elettra SincrotroneTrieste) -
16
Evaluation of Kovar for buttons BPMs
As part of our current facility upgrade, we are developing Beam Position Monitors (BPMs) designed for integration into a copper vacuum chamber. Following the preliminary design phase, the manufacturer suggested utilizing Kovar as an alternative to stainless steel for the housing. This presentation aims to discuss the implications of this material shift with the community, supported by Opera simulation results regarding magnetic field interference and thermal performance.
Speaker: Laura Torino (ALBA-CELLS) -
17
Electromagnetic Resonances near BPMs: Impact of Vacuum Chamber Discontinuities on BPM Signal Integrity
Electromagnetic resonances localized near Beam Position Monitors (BPMs) can significantly distort the beam induced signal on the electrodes and compromise BPM readings. At the European Synchrotron Radiation Facility (ESRF), a detrimental resonance was identified in the vicinity of a BPM. It originates from a small break in the electrical continuity (~2-3µm) due to the nearby RF gasket that expands and deforms during the bakeout. But other small gaps (for example from welds) may create similar resonances.
To prevent such a situation in SOLEIL II under-design storage ring, we are investigating the situation around the BPM that are integrated on bending magnet vacuum chamber. There is indeed a welding between two pieces of vacuum chambers located 30 mm from the BPM buttons creating a possible cavity. In collaboration with colleagues from ESRF, we have initiated simulation studies to assess the influence of such welding on nearby BPM readings. This contribution does not present results, but aims to trigger a discussion and gather feedback from the community, particularly regarding experience with possible resonances at welding location, simulation practices, and strategies to suppress or mitigate such effects.Speaker: moussa El Ajjouri (Synchrotron SOLEIL)
-
13
-
10:30
COFFEE
-
Session: 5Convener: Lorraine Bobb (Diamond Light Source)
-
18
BPM electronics upgrade in the scope of SOLEIL II
SOLEIL II is the low emittance upgrade project for SOLEIL light source. Dark period is foreseen in October 2028 for a duration of 2 years (including commissioning time).
In this scope, it has been decided to anticipate the upgrade of the old BPM electronics to:
• Develop the commissioning tools on the new system and its final interfaces.
• Restart the new machine with an already validated and operational BPM system which is a key diagnostic for an efficient commissioning.
220 commercial Libera Brilliance Plus modules have been delivered at the end of 2025, and one cell of SOLEIL storage ring (7 BPMs) is already equipped with the new system.
The talk will focus on:
• The dedicated hardware and software developments that have been done by Instrumentation Technologies to fit SOLEIL requirements,
• The FAT and (ongoing) SAT results
• The strategy that is followed to upgrade such a critical system on an operational machine.Speaker: Nicolas HUBERT (Synchrotron SOLEIL) -
19
Test of the iTech XBS-FE module with the Spark BPM electronics
We have acquired 2 XBS-FE modules from iTech to perform tests with real beam signals and to evaluate their performance for enhancing the long‑term stability of the Spark electronics, and in particular by reducing their dependence on hardware temperature.
The tests were performed by controlling the switching with an home-made controller, with software‑based compensation applied externally. Switching was performed at a low frequency, each full cycle lasting 8 seconds.
The results of these tests are presented here.
Speaker: Benoit Roche (ESRF) -
20
Overview of FOFB developments for PETRA IV
We will report on various simulations and measurements that we have carried out for the FOFB signal chain of the PIV project. These include the fast corrector, the vacuum chamber, the simulation framework and other blocks.
Speaker: Sven Pfeiffer (DESY) -
21
First Beam Commissioning Experience with the RF System-on-Chip Based SLS 2.0 Filling Pattern and Multi-Bunch Feedback
For the new SLS 2.0 storage ring, we have replaced the SLS 1.0 filling pattern feedback (FPFB) and multi-bunch feedback (MBFB) systems with newly developed systems that deploy RF System-on-Chip (RFSoC) technology for data conversion, signal processing, communication and control system integration. In this contribution, the status and first beam commissioning experience will be presented.
Speaker: Boris Keil (PSI - Paul Scherrer Institut) -
22
Connection Checker for the Elettra 2.0 eBPM System
The upgrade of the Elettra synchrotron to the ultra-high brightness Elettra 2.0 requires the installation of a new electron Beam Position Monitor (eBPM) system. The infrastructure comprises 168 BPMs, each featuring a complex signal chain: two pairs of four-conductor RF cables connecting the pickups to the RF front-end (PTFE), followed by five-conductor RF cabling and a network link to the DAQ10SX acquisition unit.
With over 3,000 cables and 6,000 total connections—including triggers, clocks, and data networks—systematic validation is critical. To ensure reliable beam trajectory measurements from the onset of machine commissioning, it is essential to verify that all physical links and associated subsystems are correctly mapped and fully operational.
This contribution describes the dedicated hardware and software tools developed for this purpose. We outline the automated test strategy, the verification workflow, and the management of the data collected during the large-scale installation phase.Speaker: Raffaele De Monte (Elettra-Sincrotrone Trieste S.C.p.A.)
-
18
-
13:00
LUNCH @OASE & COFFEE @TIME OUT
-
Session: 6Convener: Volker Schlott (PSI - Paul Scherrer Institut)
-
23
Single bunch phase measurement
Accurate knowledge of the longitudinal phase of individual bunches relative to a reference RF signal is essential for applications that demand tight synchronization, such as bunch‑by‑bunch transverse or longitudinal feedback systems. While many beam‑phase diagnostics exist, they are not always optimal with sparse‑filling or single‑bunch operation.
Here we would like to discuss a method for measuring the phase of a single bunch directly from a BPM button signal, without using ultra fast ADC. The approach is based on IQ demodulation at the reference RF frequency, and moderately fast ADC. The system aims to be simple, low‑cost, and readily integrable.
Applied to our booster synchrotron, it would generates a beam‑synchronous reference signal that follows the rapidly varying beam phase throughout the acceleration cycle, enabling synchronous measurements even when only a single bunch is present.
Speaker: Benoit Roche (ESRF) -
24
Overview of Silicon Carbide detector for synchrotron environments
Silicon carbide (SiC) sensors have been widely validated as compact, radiation-hard, and high-resolution X-ray beam diagnostics elements, able to perform in-line beam intensity and position monitoring with minimal perturbation of the photon beam.
The intrinsic properties of SiC as a wide-bandgap semiconductor, thermal and radiation resistant, with a silicon-like industrial maturity, make it particularly suitable for high-brilliance photon sources and harsh radiation environments.
This contribution provides an overview of different SiC-based detector concepts developed across a wide range of beamline conditions, from white-beam to monochromatic X-rays.For high-power polychromatic beams, non-fully intercepting SiC sensors have been developed as white-beam monitors, capable of operating directly in the front-end sections of synchrotron beamlines. These devices typically feature a central aperture allowing the main photon beam to pass, while collecting a fraction of the radiation halo and higher-energy harmonics. The detection mechanism relies on internal photoemission at the semiconductor interface, providing signals significantly larger and more stable than conventional metal blade monitors. This approach enables robust beam intensity and position diagnostics upstream of monochromators, where radiation levels and spectral bandwidth would rapidly degrade conventional semiconductor detectors.
Among the most innovative monochromatic beams SiC detectors, resistive X-ray beam position monitors (rXBPMs) exploit lateral charge division on a resistive layer. Unlike conventional segmented XBPMs, whose response depends on the beam spot size and geometry, rXBPMs measure the beam centroid independently of the beam-spot size, enabling more robust and calibration-free position monitoring over a wide range of beam conditions.
Speaker: Gabriele Trovato (University of Catania) -
25
Complexities in Designing Front-end XBPMs for APPLE Insertion Devices for Diamond-II
With the move to a 4th generation light source for Diamond-II, modifications to the front-end X-ray beam position monitors (XBPMs) are required to prevent damage due to the higher power loads. Several Diamond beamlines use advanced planar polarized light emitting (APPLE) undulators, which provide variable polarisation of the X-ray beam, including circular polarisation to minimise on-axis power provided to the beamline. The different transverse beam profiles resulting from the polarisations means that solutions for the APPLE-II XBPMs are a compromise between position sensitivity and risk of damage. The APPLE-Knot undulator for the I05 beamline in Diamond-II has provided further challenges in the design of the XBPMs due to the complex power densities provided by the magnetic fields present in the insertion device. Solutions found for APPLE-II XBPMs will be presented, as well as the design challenges caused by the X-ray beam profile from the APPLE-Knot.
Speaker: Samuel Jackson (Diamond Light Source) -
26
Status and Prospects of Readout and Control Systems for Real-Time X-ray Beam Monitoring at SenSiC GmbH
SenSiC GmbH is a Swiss technology company delivering advanced Silicon Carbide (SiC)–based
sensor solutions and customized electronics for high-brilliance X-ray and particle beam diagnostics.
Originating as a spin-out of the R&D activities of the Swiss Light Source (PSI), SenSiC designs and
manufactures ultra-compact, radiation-hard beam position (XBPM) and intensity monitors tailored
for high-brilliance X-ray beams in synchrotron and accelerator facilities.
Besides the SiC sensors, which will be presented by Dr. Trovato in this workshop, a central
element of the detection platform is the PCR4, a multichannel pico-to-milliammeter system designed
for the readout of SiC X-ray Beam Position Monitors (XBPMs). The system performs bipolar current
measurements across a very wide dynamic range, from ±2.5 nA up to ±50 mA, with nominal
resolution down to a few femtoamperes, noise levels down to 1 ppm (@10 Hz) with respect to the
selected current range, and sampling frequencies up to 10 kHz at 24-bit resolution. It integrates a
programmable sensor bias source (±20 V) and communicates through standard Ethernet interfaces
compatible with both EPICS- and TANGO-based control infrastructures. This architecture enables
accurate current measurements across more than five decades, supporting precise beam diagnostics
and high-resolution spatial monitoring of synchrotron radiation beams, the system has been tested in
multiple beamlines at PSI/SLS. The PCR4 also incorporates a proportional–integral feedback control
system for active beam stabilization. The system has been experimentally validated at the SOLEIL
synchrotron (GALAXIES beamline), where slow drifts during energy-scan experiments were
effectively compensated, reducing the RMS beam displacement from approximately 15 µm to about
1 µm at the feedback monitor.
Together with this system, the company is now working on three important developments: (i)
dual-sensor monitoring, (ii) multi-sensor asynchronous readout, and (iii) Enhanced Lateral
Resolution (ELR) Front-Ends (FE).
(i) By using a multi-input multi-output (MIMO) controller based on signals from two
synchronized XBPMs, it will be possible to reconstruct, and correct in real time, both beam tilts and
beam offsets thus compensating the angular and translational components of beam motion and
enabling stabilization directly at the sample location. First experimental tests on this new system are
planned for May at the SOLEIL synchrotron.
(ii) Multi-sensor asynchronous readout (MUX) enables the connection of up to 16 signal channels
and 4 bias lines, corresponding to the monitoring of up to four XBPMs. This architecture allows
several beam position monitors, each optimized for a specific photon-energy range, to be operated
and read out using a single acquisition system without the need for parallel hardware. The MUX
system is fully integrated with EPICS and TANGO control frameworks, the system has been tested
at BESSYII synchrotron facility.
(iii) ELR-FE circuits are dynamically adjustable transimpedance stages capable of optimizing
the mapping between sensor signal and the ADC input range. They allow maximizing sensitivity thus
enabling significant improvements in beam position lateral resolution. Preliminary results indicate
resolution enhancements exceeding a factor of five, benefiting all sensor types but particularly
improving the performances of resistive-XBPM and White-beam sensors.
These results demonstrate the effectiveness of the PCR4 platform for high-dynamic-range beam
diagnostics and active beam stabilization, while ongoing developments aim to further extend the
capabilities of SiC-based instrumentation to meet the increasingly stringent requirements of real-time
beam monitoring in modern high-brilliance synchrotron beamlinesSpeaker: Massimo Camarda (SenSiC GmbH)
-
23
-
16:10
Closing Remarks
-