A wide-aperture dynamically focusing sagittal monochromator for X-ray spectroscopy and diffraction

Abstract

A scanning dynamically focusing sagittal X-ray monochromator accepting 7mrad of the fan from a 6T wiggler is in routine use on beamline 16.5 (ultra-dilute spectroscopy) of the SRS at CCLRC Daresbury Laboratory, UK. The energy range covered is 7-27keV, with a horizontal spot size of <1.1mm FWHM. Measured monochromatic flux from a Si 220 crystal pair is 1 × 10 11photons s-1 (100mA)-1 at 9keV. This level of flux, usually associated with an insertion device on a third-generation source, permits collection of EXAFS data on concentrations at or below 10ppm. © 2006 International Union of Crystallography Printed in Great Britain - All rights reserved.