FEL2026 - 42nd International Free Electron Laser Conference

Coherent Twin-Pulse Generation at XFELs: Dual- Injector-Laser Production of Electron Bunch Pairs for SASE, HXRSS and PWFA

TUX03

25 Aug 2026, 09:10

20m

Invited Oral Presentation Session 4: SASE FEL SASE FEL (Invited)

Speaker

Ingmar Hartl (Deutsches Elektronen-Synchrotron DESY)

Description

The recently commissioned dual NEPAL photocathode laser systems at EuXFEL and FLASH enable the generation of twin electron bunches with unprecedented flexibility. Each laser pulse can be independently tuned in pulse energy, temporal and longitudinal profile, and relative timing, allowing for electron bunch production in the same or any two 0.77 ns spaced RF buckets. This capability unlocks novel operation modes at both facilities, such as: Twin SASE or self-seeded hard X-ray pulses without split-and delay unit and driver-witness bunch production for laser-plasma wakefield acceleration. At EuXFEL, twin X-ray pulse operation is currently being considered for first users in October this year.