Monochromator for a soft X-ray photochemistry beamline BL27SU of SPring-8

A high-resolution monochromator with varied line space plane gratings (VLSG) and spherical focusing mirrors was installed in one of three branches of BL27SU in SPring-8. The performance of the monochromator was roughly evaluated from the photo ion yield of nitrogen molecule. Furthermore, the kinetic energy of the photoelectron from Xe 5p(3/2) orbit was also measured at the same photon energy with the N-2 to avoid the influence of natural width. The resolving power over 10(4) has been confirmed at the N K-edge. (C) 2001 Elsevier Science B.V. All rights reserved.