Tests of an asymmetric monochromator to provide increased flux on a synchrotron radiation beamline.

Asymmetric channel-cut monochromators have been tested at the SRS. Results from both focused and unfocused beamlines have shown a threefold improvement in flux when compared with the flux obtained from a symmetric cut Si(111) monochromator. Some problems with using such monochromators and possible modifications are described.