A high energy X-ray scattering beamline for the ESRF

Abstract

High energy photon or gamma-ray scattering ( E > 100 keV) is a widely recognised technique in condensed matter physics which has specific advantages. For instance, when performing diffraction experiments the low absorption, the small Bragg angles and the small wavelengths substantially reduce or eliminate corrections for absorption, polarisation and extinction, and facilitate sample environment control. A major shortcoming of both elastic and Compton scattering using high energy photons is the relatively weak intensity produced by the nuclear gamma-ray sources which have mainly been used until now. The availability of bright high energy synchrotron radiation sources and the development of adequate X-ray optics will permit a gain of several orders of magnitude in flux and open up new experimental possibilities, for instance high Q scattering and studies of anharmonicities. While designed mainly for diffraction experiments, the instrument recently proposed for the European Synchrotron Radiation Facility in Grenoble also provides the possibility of Compton scattering studies [1].