Inelastic x-ray scattering measurements at BM29

An inelastic x-ray scattering spectrometer has been implemented on the bending magnet beamline BM29 at the ESRF. It comprises a spherically bent perfect crystal as a Bragg analyser in near back reflection and a linear position sensitive detector (PSD) in Rowland's geometry. The setup exploits the wide horizontal radiation fan from a dipole magnet to create an extended source so that several eV of scattered radiation are simultaneously imaged onto the PSD with a static analyser crystal. This is in contrast to existing configurations using undulator or wiggler sources where one component of the emission spectrum is imaged and the analyser has to be scanned in angle. Results are shown at the holmium L-III edge where the resolution is better than similar to 0.3 eV throughout the whole spectrum.