Please note: these are the design specifications. Potential users should contact the B18 beamline team to discuss current capabilities.
The design of B18 is based on three main optical elements: a collimating mirror, a water-cooled double crystal monochromator and a focusing mirror.
The first element is a water-cooled, vertically collimating Si mirror, which is placed at 20 m from the source. It is coated with Cr and Pt stripes and will be able to cover the whole energy range from 2 to 35 keV.
The fixed exit double crystal monochromator is water cooled and capable of fast scanning. It has two sets of crystals, Si(111) and Si(311), that can be translated horizontally under vacuum to allow a rapid configuration change. A double toroidal mirror, coated again with Cr and Pt, is placed at 25 m from the source to focus the two beam branches horizontally and vertically onto the sample. The position of this mirror is also fixed in the vertical and horizontal directions. Finally, a pair of smaller plane mirrors for harmonics rejection will be placed in the Experimental Hutch. They will be inserted in the beam path for low energy (<11 keV) operations.