Present Status of Pin-post Water-cooled Silicon Crystals for Monochromators of SPring-8 X-ray Undulator Beamlines

Several monochromator first silicon crystals of SPring‐8 undulator beamlines are effectively cooled with water at lower running costs. The crystals were newly designed and the fabrication process was improved in order to reduce various strains to deteriorate the performance. Results of performance tests show that the initial performance of the crystal has been enhanced sufficiently. Deterioration of the performance with time is discussed as a remaining problem.