PERFORMANCE OF A VERSATILE INSTRUMENTATION FOR INELASTIC X-RAY-SCATTERING SPECTROSCOPY (IXSS) WITH SYNCHROTRON RADIATION

The performance and test of an instrument for inelastic X-ray scattering spectroscopy (IXSS) using synchrotron radiation from the HARWI wiggler at DESY/HASYLAB, Hamburg, are described. The instrument can be used both for Compton profile measurements with 0.13 a.u. momentum space resolution using 32 keV X-rays and for measurements of the electronic dynamic structure factor S(q, omega) with 1.6 eV resolution using 13.7 keV X-rays. The fixed-exit monochromator consists of a plane water-cooled Si (511) crystal acting together in a nondispersive setup with a cylindrically bent sagittally focusing second Si (511) crystal. The energy analysis for Compton profile measurement is performed by means of a Cauchois-type cylindrically bent Si crystal and a 1D position sensitive 200-strip Ge detector. The energy analysis for S(q, omega)-measurements is done by using a spherically bent nearly back-reflecting Si crystal in full Rowland geometry, where the advantages of dispersion compensation are fully exploited. Test measurements on Si (Compton profiles) and graphite (S(q, omega)) are presented.