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 µJ at a wavelength of 12.4 nm (i.e.photon energy of 100 eV) with an electron beam energy of 780 MeV.
Improved free-electron laser stability and performance using a hollow electron beam
