Setup for inelastic x-ray scatering at XDS beamline

S. A. CEPPI

Campinas

Seminario; 23º Reunión anual de usuarios; 2013

LNLS

Since a decade ago, inelastic x-ray scattering (IXS) experiments have been performed at the XRD1 beamline of the LNLS with high energy resolution but with a very limited photon flux. The construction of the new wiggler beamline at the LNLS (XDS) will open up the possibility of carrying out new IXS experiments with even better resolution and much higher photon fluxes thanks to the superior x-ray beam quality provided by this source . In this work we present a new setup to be mounted at the XDS beamline to perform IXS experiments with sub-eV energy resolution along with high counting rates. This beamline has a 6+2 circle goniometer which will allow measurements on horizontal, vertical and oblique scattering planes to be performed, while the momentum transfer will can be continuously modified by changing the scattering angle. In order to improve even more the energy resolution we propose to extend the spectrometer arm to 1 m and at the same time to construct analyzer crystals with larger curvature radius. The implementation of the dispersion-compensation method, along with a linear detector, has been considered. The setup design is aimed to two configurations, a high energy resolution mode (0.5 eV, with an incident beam intensity of 2*10 ^11 photons /s/100mA) and a high flux mode (1*10^13 photons /s/100mA photons / s, with an energy resolution of 1 eV). This setup will provide access to the experimental study of valence and core electronic excitations in condensed matter by means of the inelastic x-ray scattering spectroscopy both using resonant and non-resonant regimes