1st Hard X-ray Self-seeding Workshop (HXRSS 2025)

Oct 15, 2025, 1:30 AM → Oct 17, 2025, 10:45 PM Asia/Seoul

PAL-XFEL Auditorium (PAL, Pohang, Korea)

Gianluca Geloni

We are pleased to announce the first Self-seeded FEL workshop will be held in Pohang, South Korea. This workshop aims to share new ideas and promote collaboration in self-seeded FEL techniques and their scientific applications.

Today, Self-seeding is the only scheme that provides hard X-ray FEL users with pulses of radiation characterized by high-brightness (an order of magnitude higher than SASE) and narrow-bandwidth (down to a fraction of eV). Four facilities, LCLS-I, SACLA, PAL-XFEL, and European XFEL, use a self-seeded scheme for narrow-band scientific applications. At upcoming CW XFEL facilities, like SHINE and LCLS-II, self-seeding is considered for advancing the scientific case.

The workshop topics will include X-ray FEL self-seeding techniques and their science cases, including their development and applications, discussions on collaboration, etc. During the workshop, all participants are invited to have a hands-on experience of joining the self-seeded FEL tuning and optimization team at the PAL-XFEL operation room.

Topics to be discussed:

• experiments (cool things we can do with it)
• current performance (or expected performance from facilities that will install it)
• developments and schemes (transmission/reflection, single/double chicane, harmonics, phase locking)

 

HXRSS_Workshop_PAL_timetable_20251015.pdf

Wed, October 15

7:30 AM Bus Pickup and Transfer to Venue

Bus pickup at Hotel Lahan

8:00 AM Registration

Breakfast(sandwich) at multipurpose room
&
Registration in front of PAL-XFEL auditorium

Session A: Introduction and perspectives

1 Workshop introduction and goals - general introduction to HXRSS

Speaker: Gianluca Geloni (European XFEL)

HXRSS2025_intro.pdf

2 Coherence Control and Limitation with HB SASE

Speaker: Philipp Dijkstal (Paul Scherrer Institut)

HB_SASE_HXRSS.pptx

3 Extrapolation of EEHG towards higher photon energies

Speaker: Enrico Allaria (Elettra - Sincrotrone Trieste)

4 Overview of cavity based XFEL activities

Speaker: Nanshun Huang (Shanghai Optoelectronic Science and Technology lnnovation Center)

5 The cavity-based XFEL demonstrator at the European XFEL

Speaker: Patrick Rauer (Deutsches Elektronen-Synchrotron DESY)

FirstLasingCBXFEL.pptx

FirstLasingOfCBXFELEuXFEL

11:00 AM Coffee Break

Session B: Current performance

6 Self-seeding FEL for experiments requiring energy scans at PAL-XFEL

Speaker: Haeryong Yang (Pohang Accelerator Laboratory)

7 High repetition rate HXRSS system at the European XFEL

Speaker: Shan Liu (DESY)

8 Recent activities of hard X-ray self-seeding at LCLS

Speaker: Alberto Lutman (SLAC)

9 Daily optimization of reflection self-seeding

Speaker: Dr Toru Hara (RIKEN SPring-8 Center)

10 Discussion (B)

1:30 PM Lunch

Session C: Developments and schemes (I)

11 Self-seeding option and status at SHINE

Speaker: Tao Liu (Shanghai Advanced Research Institute, CAS)

12 Bandwidth and signal to noise ratio control for hard X-ray self-seeding

Speaker: Tianyun Long (DESY)

13 Pulselength Control in Self-Seeding

Speaker: Philipp Dijkstal (Paul Scherrer Institut)

14 Development and applications of combined self-seeding and crystal optics

Speaker: Ichiro Inoue (The University of Tokyo)

15 Discussion (C-I)

Self-Seeding Demo.

16 Accelerator Demo.

17 Beamline Demo.

Banquet

POSCO International Center, Buffet

8:00 PM Move to Hotel Lahan

Thu, October 16

7:30 AM Bus Pickup and Transfer to Venue

Bus pickup at Hotel Lahan

8:00 AM Breakfast

Breakfast(sandwich) at multipurpose room

Session C: Developments and schemes (II)

18 Generation of tunable phase-locked hard X-ray pulses

Speaker: Philipp Dijkstal (Paul Scherrer Institut)

19 Comparison same bunch and fresh bunch self seeding at PAL

Speaker: Myunghoon Cho (Pohang Accelerator Laboratory)

(20251010)ss.pptx

20 Self-seeding at higher harmonics

Speaker: lu cao (Deutsches Elektronen-Synchrotron DESY)

21 Self-seeding systems for CW FELs - Remote

Speaker: David Reis (Stanford PULSE Institute)

22 Advanced studies at the LCLS - Remote

Speaker: Aliaksei Halavanau (SLAC National Accelerator Laboratory)

23 Discussion (C-II)

11:10 AM Coffee break

Session D: Experiments (I)

24 IXS challenges - Remote

Speaker: Mark Dean

25 Dynamics of compressed gas/liquid (CO2, water, alcohol)

Speaker: Matthias Ihme (Stanford University)

26 Water dynamics

Speaker: Robin Tyburski (Stockholm University)

27 Discussion (D-I)

1:15 PM Lunch

Lunch at multipurpose room

Session D: Experiments (II)

28 Time-resolved Bragg Coherent X-ray Diffraction Imaging of Ferroelectric Transition

Speaker: Hyunjung Kim (Soagng University)

29 3D time-resolved single-shot imaging

Speaker: Changyong Song (POSTECH)

30 Discussion (D-II)

PAL-XFEL Tour

5:05 PM Move to restaurant

Social Dinner

Fri, October 17

7:30 AM Bus Pickup and Transfer to Venue

Bus pickup at Hotel Lahan

8:00 AM Breakfast

Breakfast(sandwich) at multipurpose room

Session D: Experiments (III)

31 Single-shot structure determination under high magnetic field over 100 T

Speaker: Akihiko Ikeda (University of Electro-Communications, Tokyo, Japan)

32 Atomic-scale imaging of strong-field optically induced electron motion in imperfect crystals - Remote

Speaker: David Reis (Stanford PULSE Institute)

33 Scandium-45 Nuclear-Clock Isomer driven by hard X-ray self-seeding - Remote

Speaker: Yuri Shvydko (Argonne National Laboratory)

251017-Sc45-XFELs.pdf

34 Discussion (D-III)

10:45 AM Coffee break

Session D: Experiments (IV)

35 Application of hard X-ray self-seeding at higher photon energies

Speaker: Angel Rodriguez Fernandez (European XFEL)

36 Nonlinear spectroscopy utilizing two-color pulses composed of seeded and broadband beams

Speaker: Thomas Linker (SLAC)

HXRSS_Linker.pptx

37 Ultrafast Photocatalytic Reaction Dynamics Probed by HERFD-XAS with Self-seeded XFEL Pulses

Speaker: Tae Wu Kim (Kyung Hee University)

38 Discussion (D-IV)

39 Overall discussion and wrap-up

1:20 PM Lunch box pickup & Move to Pohang KTX station