Monochromator
The monochromator chamber is bolted on two granit blocks (2 tons in total) also bolted onto the concrete floor. The monochromator crystal is kept under high vacuum and cryocooled by liquid nitrogen. It has been carved in a single Silicon (111) crystal whith a channel in the middle, called channel-cut design.This design has the main advantage of having only one crystal for both diffraction side but still allows twicking by rotating the second diffracting part of the crystal (pusher motor m1).
The monochromator and its chamber are entirely motorised:
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translation of the chamber (perpendicular to the Xray beam) in order to use either crystal 1 or crystal 2 (not yet implemented)
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rotation of the crystal (motor mono) from 5.5° to 27° (i.e. from 20.600 keV to 4.300keV)
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pusher to twick the second diffracting part of the crystal (motor push111)