Setup for meV-resolution inelastic X-ray scattering measurements at the Matter in Extreme Conditions Endstation at the LCLS

TL;DR

This paper presents a setup for high-resolution inelastic X-ray scattering at LCLS's MEC endstation, enabling detailed measurements of ion dynamics in extreme conditions with potential applications in warm dense matter research.

Contribution

The paper introduces a novel setup combining a silicon monochromator and analyzers for ~50 meV resolution in inelastic X-ray scattering at LCLS, suitable for extreme condition studies.

Findings

Achieved ~50 meV energy resolution in single shot measurements.

Demonstrated measurement of longitudinal acoustic phonons in polycrystalline diamond.

Potential to combine with laser drivers for warm dense matter studies.

Abstract

We describe a setup for performing inelastic X-ray scattering measurements at the Matter in Extreme Conditions (MEC) endstation of the Linac Coherent Light Source (LCLS). This technique is capable of performing high-, meV-resolution measurements of dynamic ion features in both crystalline and non-crystalline materials. A four-bounce silicon (533) monochromator was used in conjunction with three silicon (533) diced crystal analyzers to provide an energy resolution of ~50 meV over a range of ~500 meV in single shot measurements. In addition to the instrument resolution function, we demonstrate the measurement of longitudinal acoustic phonon modes in polycrystalline diamond. Furthermore, this setup may be combined with the high intensity laser drivers available at MEC to create warm dense matter, and subsequently measure ion acoustic modes.