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A short working distance multiple crystal x-ray spectrometer

B. Dickinson·G.T. Seidler·Z.W. Webb·J.A. Bradley·K.P. Nagle·S.M. Heald·R.A. Gordon·I.-M. Chou
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Abstract

For x-ray spot sizes of a few tens of microns or smaller, a millimeter-sized flat analyzer crystal placed ???1 cm from the sample will exhibit high energy resolution while subtending a collection solid angle comparable to that of a typical spherically bent crystal analyzer (SBCA) at much larger working distances. Based on this observation and a nonfocusing geometry for the analyzer optic, we have constructed and tested a short working distance (SWD) multicrystal x-ray spectrometer. This prototype instrument has a maximum effective collection solid angle of 0.14 sr, comparable to that of 17 SBCA at 1 m working distance. We find good agreement with prior work for measurements of the Mn K?? x-ray emission and resonant inelastic x-ray scattering for MnO, and also for measurements of the x-ray absorption near-edge structure for Dy metal using L??2 partial-fluorescence yield detection. We discuss future applications at third- and fourth-generation light sources. For concentrated samples, the extremely large collection angle of SWD spectrometers will permit collection of high-resolution x-ray emission spectra with a single pulse of the Linac Coherent Light Source. The range of applications of SWD spectrometers and traditional multi-SBCA instruments has some overlap, but also is significantly complementary. ?? 2008 American Institute of Physics.

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B. Dickinson, G.T. Seidler, Z.W. Webb, J.A. Bradley, K.P. Nagle, S.M. Heald, R.A. Gordon, I.-M. Chou. 2008-12-23. A short working distance multiple crystal x-ray spectrometer. https://doi.org/10.1063/1.3048544

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