A diamond double‐crystal transmission monochromator for the TROIKA II station at ESRF Available to Purchase

The performance of a diamond double‐crystal monochromator for the TROIKA II station at the ESRF was studied. Two (111) oriented diamond crystals for Bragg geometry (120 mm and 500 mm thick) were combined in a nondispersive horizontal scattering geometry and characterized in the white Troika undulator beam. The observed rocking curves were slightly broadened due to nonuniform defect distributions present in the crystals. No heat‐load‐induced broadening was found. The measured reflectivities compared well to the calculated values, and it was shown that a double‐crystal Bragg monochromator can replace a single‐reflection Laue monochromator without loss in flux.