NEW APPROACH TO THE COOLING OF FIXED EXIT DOUBLE-CRYSTAL MONOCHROMATOR AT THE EUROPEAN SYNCHROTRON-RADIATION FACILITY

The stability and reproducibility of positioning of the fixed exit dou ble crystal monochromator are the crucial points at the modern synchro tron beamlines dealt with the high resolution imaging techniques and m icroscopy at high energies. Due to high heat load, the monochromator c rystals must be cryogenically cooled. The cooling loop of the second c rystal impact the performance of the monochromator. We suggest the use of the silicon-germanium (Si1-xGex) bulk crystal as the first cooled crystal of the monochromator. The second crystal in that case is held at room temperature. (C) 1997 American Institute of Physics.