UHV-compatible fixed-exit two-crystal monochromator

The principal objective for the monochromator is to be fixed exit. In addition the design is kept simple, practical and inexpensive. The monochromator design is based on the Cowan boomerang linkage. It has the ability to accept 18 mrad at a distance 12 m from the bending magnet. The crystals are at least 220 mm wide. The water cooling for the first crystal and the bending mechanism for the second have considerable weight. This design supports the crystals on either ends, thus the bearings can be much smaller. Due to the small size of the bearings, the monochromator infrastructure takes up less space. Ultra-high-vacuum compatibility is also one main concern. Though the monochromator will likely operate most of the time with Si(111) crystals, working with other crystals, other 24 spacings, and different energy ranges is being anticipated.