FEL2026 - 42nd International Free Electron Laser Conference

Session

Undulators and Photon Beamline Instrumentation (Invited)

WEX

26 Aug 2026, 08:30

157. Hard x-ray attosecond metrology via split-delay autocorrelation (WEX01)

Yanwen Sun (SLAC National Accelerator Laboratory)

26/08/2026, 08:30

Session 11: Undulators and Photon Beamline Instrumentation

Invited Oral Presentation

I will present the design and commissioning results of a broadband hard x-ray delay line for generating attosecond pulse pairs. The system utilizes an unconventional delay adjustment mechanism, in which the relative path length between the two beams is controlled through the rotation of an x-ray mirror pair. The exit beam pointing stability is guaranteed by the mirror-pair...

36. X-ray diagnostics for a Cavity-based XFEL (WEX02)

Dr Jan Grünert (European X-Ray Free-Electron Laser)

26/08/2026, 08:55

Session 11: Undulators and Photon Beamline Instrumentation

Invited Oral Presentation

European XFEL is commonly providing user operation with self-amplified spontaneous emission (SASE) and hard x-ray self-seeding (HXRSS), ref [1]. A facility-internal project had been started to demonstrate operation of a cavity-based XFEL (CB-XFEL), ref [2], which promises to improve spectral purity and brightness significantly. The first demonstration of a CBXFEL was achieved in May 2025, ref...

150. CASPER: a Compact Arbitrary Superconducting Polarisation Emitting Radiator (WEX03)

Marco Calvi (Paul Scherrer Institute)

26/08/2026, 09:20

Session 11: Undulators and Photon Beamline Instrumentation

Invited Oral Presentation

To provide fully controllable elliptical polarisation to all experimental stations of the SwissFEL facility, spanning soft to hard x-rays, the PSI ID group is developing a novel undulator concept based on HTS REBCO tapes. The proposed design enables the superposition of right-handed and left-handed helical fields with comparable strength, allowing the generation of horizontal and vertical...