Bent crystal spectrometer for both frequency and wavenumber resolved x-ray scattering at a seeded free-electron laser
Abstract
We present a cylindrically curved GaAs x-ray spectrometer with energy resolution and wave-number resolution of , allowing plasmon scattering at the resolution limits of the Linac Coherent Light Source (LCLS) x-ray free-electron laser. It spans scattering wavenumbers of 3.6 to \AA\ in 100 separate bins, with only 0.34\% wavenumber blurring. The dispersion of 0.418~eV/m agrees with predictions within 1.3\%. The reflection homogeneity over the entire wavenumber range was measured and used to normalize the amplitude of scattering spectra. The proposed spectrometer is superior to a mosaic HAPG spectrometer when the energy resolution needs to be comparable to the LCLS seeded bandwidth of 1~eV and a significant range of wavenumbers must be covered in one exposure.
Keywords
Cite
@article{arxiv.1407.7489,
title = {Bent crystal spectrometer for both frequency and wavenumber resolved x-ray scattering at a seeded free-electron laser},
author = {Ulf Zastrau and Luke B. Fletcher and Eckhart Foerster and Eric Ch. Galtier and Eliseo Gamboa and Siegfried H. Glenzer and Philipp Heimann and Heike Marschner and Bob Nagler and Andreas Schropp and Ortrud Wehrhan and Hae Ja Lee},
journal= {arXiv preprint arXiv:1407.7489},
year = {2015}
}