I.FAST Workshop 2025 on Stability of Storage Ring Based Light Sources

Mar 17, 2025, 6:30 PM → Mar 21, 2025, 2:30 PM Europe/Berlin

KARA large seminar room in building 348 (KIT North Campus)

Akira Mochihashi (Instuture for Beam Physics and Technology)

 

The I.FAST Workshop 2025 on the stability of storage ring based light sources is jointly organised by Synchrotron SOLEIL and KIT. 

For future synchrotron light sources with ultra low emittance beams, the stability of the light source is of paramount importance in order to exploit the properties of the high quality beams. Beam stability issues have been addressed as one of the relevant topics in synchrotron light sources from hardware and beam dynamics aspects, including the time range from sub-microseconds to years. The goal of the workshop is to share the latest information and knowledge on beam dynamics in order to understand and improve beam stability and the relevant hardware to ensure stable beam operation. 

The Stability Workshop will have four session blocks, namely Beam Position Stability, where beam dynamics, correction schemes, beam diagnostics will be discussed, Resistive and Permament Magnets, where stability on resistive and permanent magnets will be discussed, Infrastructure, where girders and temperature stability will be discussed, Challenging Issues, where prospects and future goals will be discussed. 

To ensure networking between the various scientific and industrial areas involved in accelerator science and technology, a joint experimental campaign will be organized immediately after the two-day workshop, where participants will jointly participate in beam stability related experiments at the Karlsruhe Research Accelerator KARA. 

 

 

 

Mon, March 17

Reception and kickoff meeting

Kickoff_Meeting_20250317.pptx

Tue, March 18

Transport from Karlsruhe to KIT Campus North

Registration

Opening

Convener: Akira Mochihashi (Instuture for Beam Physics and Technology)

1 Welcome greetings

Speaker: Akira Mochihashi (Instuture for Beam Physics and Technology)

2 General information

Speaker: Akira Mochihashi (Instuture for Beam Physics and Technology)

Source position stability: part 1

Convener: Akira Mochihashi (Instuture for Beam Physics and Technology)

3 SLS 2.0 BPM and Beam Feedback Systems - First Beam Commissioning Experience

Speaker: Dr Boris Keil (Paul Scherrer Institute)

2025_0317__KIT-iFast_Keil_SLS2_BPMs_Feedbacks_V10.pdf

2025_0317__KIT-iFast_Keil_SLS2_BPMs_Feedbacks_V10.pptx

4 Status of the design and simulations for the FOFB of PETRA IV

Speaker: Sven Pfeiffer (DESY)

1_2_SPfeiffer_Status_FOFB_PETRAIV_V2.pdf

SPfeiffer_Status_FOFB_PETRAIV_V2.pptx

10:15 AM Coffee break

Source position stability: part 2

Convener: Ian Martin (Diamond Light Source)

5 The orbit stability issue in the initial commissioning stage of High Energy Photon Source

Speaker: Dr Xiyang Huang (Institute of High Energy Physics)

iFastworkshop_huangxy_v3.pdf

6 Orbit Stability at BESSY II: Progress of FOFB Upgrade and Current Stability

Speaker: Günther Rehm (Helmholtz-Zentrum Berlin)

Orbit Stability at BESSY II Progress of FOFB Upgrade and Current Stability.pptx

7 Application of deep learning method for insertion device orbit and coupling feedforward at the SSRF

The Shanghai Synchrotron Radiation Facility (SSRF), a third-generation synchrotron radiation source, demands exceptional beam stability for high-precision user experiments. However, manufacturing and installation inaccuracies in insertion devices (IDs) can lead to beam orbit and coupling distortions. To address this, we developed a data-driven predictive model leveraging deep learning to forecast the effects of ID gap variations. The model facilitates real-time feedback control by adjusting corrector and skew quadrupole currents, effectively mitigating ID-induced perturbations on beam orbit and coupling. Implementation at SSRF demonstrates a substantial reduction in these perturbations, resulting in enhanced experimental stability and reliability.

Speaker: xinzhong liu

Application of Deep Learning Methods for Insertion Device Effects in the SSRF_IFAST.pptx

Discussion

8 Source position stability: short discussion 1

Group picture

12:25 PM Lunch Break

Source position stability: part 3

Convener: Sven Pfeiffer (DESY)

9 Orbit stability and reproducibility at SOLARIS storage ring

Speaker: Dr Adriana Wawrzyniak (SOLARIS)

Beam stability_IFAST_AW.pptx

10 Design and commissioning of the asymmetric beam optics in the SSRF storage ring

Lattice upgrade, consisting of replacing the conventional bending magnets with super-bend locally, constructing two double-mini-𝛽y optics (DMB) and installing a superconducting wiggler (SCW), was implemented in the Beamline-Project of Shanghai Synchrotron Radiation Facility (SSRF). The symmetry of the SSRF storage ring was completely destroyed, forcing the global optics to be modified. The lattice of the new SSRF storage ring, matching the new elements perfectly, was designed. Sufficient dynamic aperture and energy acceptance were obtained by elaborate lattice design and nonlinear optimization. Study on beam dynamics, including the closed orbit correction, the linear optics correction, the coupling correction, the chromaticity correction and the nonlinear dynamic optimization, achieved good results for the new lattice. The critical step in the study is the restoration of the linear beam optics, which greatly restored the machine performance. The resulting beam parameters, as well as the operation status, are also presented.

Speaker: Shunqiang TIAN (SARI, CAS)

SQTian-202503-Design and commissioning of the asymmetric beam optics in the SSRF storage ring.pptx

11 BESSY III orbit correction scheme layout and performance

Currently in its Conceptual Design Phase (CDR), the 4th generation light source BESSY III aims to become a world-leading soft X-ray source, enabling numerous applications in metrology, life sciences, energy and catalysis materials, and many more. Its performance relies on ultra-low transverse emittances, achieved through the use of strong focusing magnetic elements that are sensitive to magnetic and alignment errors.
If left uncorrected, these errors give rise to a distortion of the closed orbit, beta beating, linear coupling, and a stronger impact of resonances thus impairing the storage ring performance.
In this work, we address how to devise an initial BESSY III orbit correction scheme. Two criteria were considered to find the optimal locations of Beam Position Monitor (BPM) and dipolar Corrector Magnet (CM). Different orbit correction scheme candidates are presented and their advantages and disadvantages are discussed. All calculations were performed in parallel with the Matlab toolkit Simulated Commissioning (SC) and its Python counterpart (pySC).

Speaker: Sebastien Joly (HZB)

I_FAST25_JOLY.pdf

Source position stability: part 4

Convener: Xiyang Huang (Institute of High Energy Physics)

12 A transparent injection scheme for Diamond-II

Speaker: Ian Martin (Diamond Light Source)

KIT_Stability_DII_Injection_Mar2025.pdf

KIT_Stability_DII_Injection_Mar2025.pptx

13 Experimental Application of Neural Network Fast Feedback Modeling at the Canadian Light Source

(Online talk)

Speaker: Dr Shervin Saadat (Canadian Light Source)

IFAST_25.pptx

14 (Tentative) XBPM system development and applications

Speaker: Massimo Camarda (STLab)

SenSiC_STLab_Camarda_fin.pdf

Discussion

15 Source position stability: short discussion 2

4:50 PM Coffee break

Resistive and permanent magnets: part 1

Convener: Chamseddine Benabderrahmane (ESRF)

16 Qualification of Series Magnets in the SLS Upgrade at the Paul Scherrer Institute: Challenges, Results, and Lessons Learned

To enhance the performance of the Swiss Light Source (SLS) at the Paul Scherrer Institute (PSI), a comprehensive upgrade known as SLS 2.0 is currently underway (2021–2026). This ambitious project involves the renewal of the storage ring, achieving 40 times lower emittance in user operation mode, thereby significantly increasing the source brightness, and enabling groundbreaking research capabilities. The SLS 2.0 upgrade imposes stringent requirements on field quality and magnetic alignment across a total of 1,285 magnets, which are being magnetically qualified at PSI. For the first time in a light source facility, the storage ring will utilize a unique combination of three magnet types: 1) NdFeB-based permanent magnets, offering high field quality with minimal power consumption. 2) Combined-function electromagnets, optimizing compactness and efficiency. 3) two 5-T Nb-Ti superconducting longitudinal gradient dipoles, to be installed during the second phase of the machine upgrade. This talk will provide an overview of the magnetic measurement challenges encountered during the project, the measurement strategy and results related to permanent and electromagnets, as well as the lessons learned from executing a large-scale magnetic test campaign achieving a 10-3 relative accuracy level under tight time constraints.

Speaker: Stéphane Sanfilippo (Paul Scherrer Institute)

SLS2.0 Magnetic Measurements _IFAST 2025.pdf

SLS2.0 Magnetic Measurements _IFAST 2025.pptx

17 Elettra 2.0 magnets and girders

Speaker: Dr Davide Castronovo (Elettra Sincrotrone Trieste)

4_2_Elettra 2.0 magnets and girders.pptx

Discussion

18 Magnets and power supplies: short discussion 1

Transport from KIT Campus North to Karlsruhe

Workshop dinner

Wed, March 19

Transport from Karlsruhe to KIT Campus North

Information and announcements

Convener: Akira Mochihashi (Instuture for Beam Physics and Technology)

Additional Session

19 HEPS Fast Orbit Feedback System

Speaker: Dr Shujun Wei (Instutute of High Energy Physics, CAS)

HEPS Fast Orbit Feedback system_2025.03.18.pdf

HEPS Fast Orbit Feedback system_2025.03.18.pptx

Resistive and permanent magnets: part 2

Convener: Samira Fatehi (LAS, Karlsruhe institute of technology)

20 Radiation damage in permanent magnet materials

Online talk

Speaker: Dr Ben Shepherd (Science and Technology Facilities Council (STFC))

2025-03-19 Shepherd - Radiation damage in PMs - I.FAST Workshop on Stability of Storage Ring Based Light Sources.pptx

21 Development of permanent magnet dipoles for ESRF-EBS

Speaker: Dr Chamseddine Benabderrahmane (ESRF)

1_2_ESRF_DLs_Magnets_Benabderrahmane_19032025_I.FAST_Karlsruhe.pptx

Discussion

22 Magnets and power supplies: short discussion 2

10:40 AM Coffee break

Orientation session for the joint experiment

Convener: Akira Mochihashi (Instuture for Beam Physics and Technology)

23 Orientation talk for joint experiment: Quadrupole offset measurement by BBA

Speaker: Christian Goffing (CERN and KIT)

20250319_IFAST_Workshop_Presentation.pdf

24 Discussion: joint experiment

Experiment_Session_20250319.pdf

Experiment_Session_20250319.pptx

12:00 PM Lunch break

Infrastructure: part 1

Convener: Günther Rehm (Helmholtz-Zentrum Berlin)

25 Vibration analysis and stability control for High Energy Photon Source in China

Speaker: Dr Fang Yan (Institute of High Energy Physics)

yanfang-IHEP-ifast2025.pdf

26 Beam-based girder alignment in PETRA-IV: conceptual simulations

(Online talk)

Speaker: Dr Sajjad Hussain Mirza (DESY)

Girder_alignment_Sajjad_KIT_I.Fast.pptx

Infrastructure: part 2

Convener: Jonas Breunlin (MAX-IV)

27 Effects of the ALBA slab movement on ALBA-II

Speaker: Dr Oscar Roberto Blanco García (ALBA)

2025mar19_ALBA_II__OscarBLANCO.pdf

28 Topology-Optimized Girder Design for PETRA IV: Achieving High Eigenfrequencies for Enhanced Stability

Speaker: Normann Koldrack (DESY)

I.FAST WS Girder- Koldrack 2.pptx

Discussion

29 Infrastructure: short discussion

3:00 PM Coffee break

Challenging issues: part 1

Convener: Akira Mochihashi (Instuture for Beam Physics and Technology)

30 Statistical and interferometric beam diagnostics in IOTA at Fermilab

At the Fermilab Integrable Optics Test Accelerator (IOTA), we are
carrying out a research program on the statistical and quantum-optical
properties of undulator radiation from electron bunches down to single
electrons [1]. As a result of this program, novel beam diagnostic
techniques have been developed. From the intensity fluctuations of
undulator radiation, it is possible to infer very small beam sizes,
which would otherwise be very challenging to observe [2]. In addition,
we applied interferometric methods to observe vibrations of the
apparatus at the nanometer scale [3]. A review of these methods is
given, with an outlook on possible developments.

[1] https://doi.org/10.18429/JACoW-IPAC2024-MOPG06
[2] https://doi.org/10.1103/PhysRevLett.126.134802
[3] https://rpubs.com/gist/clara-vibration-studies https://doi.org/10.5281/zenodo.14897587

Speaker: Giulio Stancari (Fermilab / UChicago)

Stancari_iFAST_Stability_Workshop_2025-03-19.pdf

31 Beam position measurements: from pickups to stable beams

Speaker: Dima El Khechen (LAS)

iFAST2025_Elkhechen.pdf

32 Bunch-by-bunch feedback system used as a diagnostic device for multi-bunch instabilities in the DAΦNE collider

DAΦNE is an electron-positron collider operating at INFN-LNF. Bunch-by-bunch feedback systems installed in each of the two rings allow to store high-intensity and stable beams, by counteracting strong coupled-bunch instabilities due to e-cloud and RF higher-order modes. These feedback systems can be also used as a diagnostic tool which is able to measure beam parameters which are important for the evaluation of the instabilities. In this talk, we first describe the acquisition system used to record the beam data obtained with the feedback systems. Then we report transverse-tune shift and grow-damp measurements performed in 2024 with positron beams, by using the feedback as a diagnostic device. These measurements contributed to the characterization of the e-cloud beam instability, which currently is one of the main limitations for the DAΦNE performances. Finally, we describe the first beam measurements and feedback-system setup designed to automatically record turn-by-turn bunch position displacements when an unexpected loss in beam current occurs due to any faults in the collider. This tool can be useful in identifying the causes of these events.

Speaker: Danilo Quartullo (INFN-LNF)

quartullo_2025_03_19_IFASTworkshop.pdf

quartullo_2025_03_19_IFASTworkshop.pptx

Challenging issues: part 2

Convener: Dima El Khechen (LAS)

33 Observing sudden beam loss events using bunch-by-bunch BPMs at SuperKEKB

Speaker: Dr Riku Nomaru (The University of Tokyo)

IFAST2025_nomaru.pdf

34 Microbunching control and CSR stabilization at KIT-KARA

Speaker: Luca Scomparin

ifast_scomparin.pdf

ifast_scomparin.pptx

35 Development of Control Systems for the Stabilization of Synchrotron X-Ray beams

This work investigates the study, design, and implementation of a control system for stabilizing focused X-ray beams in synchrotron beamlines. Due to the challenges and high costs associated with direct and continuous access to these facilities, a custom Lab-replica was instead employed.
This replica utilizes an analog oscilloscope to represent the X-ray beam, two electromagnets to simulate disturbances, and two electrical deflection plates to replicate the actuation system. A custom detection system was integrated to identify a first-order experimental model, establishing a correlation between the light spot position on the oscilloscope screen and the input voltage signals of the replica's actuators. Based on this model, a PID control loop was designed and validated, first through simulations and later through experimental campaigns.

As a proof of concept, a typical disturbance encountered in X-ray Absorption Spectroscopy (XAS) was simulated by inducing drift in the Lab-replica setup using an electromagnet. The PID controller, tested at control frequencies up to 1 kHz, successfully tracked the reference signal, maintaining an error below 0.2% of the total drift and achieving a rise time of less than 15 ms. These results demonstrate the controller’s effectiveness in mitigating beam drift within the Lab-replica, highlighting its potential for optimizing real XAS measurements.

Speaker: Niccolò La Rosa

i_Fast_Niccolo_La_Rosa.pptx

Discussion

36 Discussion: Stability issues in general

Closing remark and information

Convener: Akira Mochihashi (Instuture for Beam Physics and Technology)

Closing_Remark_20250319.pdf

Transport from KIT Campus North to Karlsruhe

Thu, March 20

Transport from Karlsruhe to KIT Campus North

Organization

Joint experiment

12:00 PM Lunch break

Joint experiment

Discussion

37 Joint experiment: discussion 1

Transport from KIT Campus North to Karlsruhe

Fri, March 21

Transport from Karlsruhe to KIT Campus North

Joint experiment

Discussion

38 Joint experiment: discussion 2

12:00 PM Lunch break

Transport from KIT Campus North to Karlsruhe