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arXiv · 0809.3617

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 mm-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 non-focusing 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 meter working distance. We find good agreement with prior work for measurements of the Mn K_beta x-ray emission and resonant inelastic x-ray scattering (RIXS) for MnO and also for measurements of the x-ray absorption near-edge structure for Dy metal using Lalpha2 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.

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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. 2008-09-21. A Short Working Distance Multiple Crystal X-ray Spectrometer. https://doi.org/10.1063/1.3048544

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