A soft X-ray free-electron laser beamline at SACLA: the light source, photon beamline and experimental station

Abstract

The design and performance of a soft X-ray free-electron laser (FEL) beamline of the SPring-8 Compact free-electron LAser (SACLA) are described. The SPring-8 Compact SASE Source test accelerator, a prototype machine of SACLA, was relocated to the SACLA undulator hall for dedicated use for the soft X-ray FEL beamline. Since the accelerator is operated independently of the SACLA main linac that drives the two hard X-ray beamlines, it is possible to produce both soft and hard X-ray FEL simultaneously. The FEL pulse energy reached 110 mJ at a wavelength of 12.4 nm (i.e. photon energy of 100 eV) with an electron beam energy of 780 MeV.

Characterization of soft X-ray FEL pulse duration with two-color photoelectron spectroscopy

“…The experiment was performed at the endstation of SACLA BL1 [0.2-0.3 nC per bunch, 0.5-0.8 MeV (Owada et al, 2018)]. The incident FEL beam (h = 40-120 eV, ÁE/E ' 0.02, $ 24 mJ per pulse) was introduced to a wavefront-splitting mirror (an elliptic cylindrical mirror with a sharp edge) for the arrival time diagnostic.…”

Time-resolved photoelectron angular distributions from nonadiabatically aligned CO2 molecules with SX-FEL at SACLA

“…The experiments were performed at the SX beamline BL1 at SACLA [53]. The SX-FEL was operated at the wavelength of 22.4 nm (55.4 eV) and the bandwidth of ∼2% (∼1 eV).…”

“…In the above mentioned context, prior to the final goal of the UXPD, here we present the time-resolved PADs from an aligned CO 2 molecular ensemble with the femtosecond soft x-ray (SX) pulses from SACLA SX-FEL [53]. The aligned molecular ensemble was prepared using the SACLA in-house Ti:sapphire NIR laser [54], and then evolves under field-free conditions.…”

Coulomb implosion of tetrabromothiophene observed under multiphoton ionization by free-electron-laser soft-x-ray pulses

“…The experiments were carried out at beamline 1 (BL1) [23] of the SACLA free-electon-laser facility [24] operating at a repetition rate of 60 Hz. The pulse duration of the x-ray FEL was estimated to be about 70-fs full width at half-maximum.…”