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arXiv · 2610.24989

HEXRD and HEXRDGUI: a flexible toolkit for X-ray diffraction analysis in dynamic compression experiments

Patrick Avery·Joel V. Bernier·Brianna Major·Saransh Singh
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Abstract

This article describes the application of HEXRD, an open-source Python library for X-ray diffraction analysis, and HEXRDGUI, its companion graphical application, to dynamic compression experiments. Built on a generic multi-detector geometric model, the toolkit supports arbitrary instrument configurations with independently positioned planar or cylindrical detector panels, arbitrary beam directions, and multiple X-ray sources. It calibrates instruments from powder rings, Laue spots or the rings of an unknown phase, fits whole patterns by Le Bail or Rietveld refinement, and imports data from the TARDIS, FIDDLE and PXRDIP platforms at the National Ignition Facility (NIF) and OMEGA EP. Although originally developed for high-energy diffraction microscopy at synchrotron sources, HEXRD has been adopted as an analysis tool for dynamic compression X-ray diffraction experiments at facilities including the NIF, the Matter in Extreme Conditions end-station at the Linac Coherent Light Source, the Dynamic Compression Sector (DCS) at the Advanced Photon Source, OMEGA EP at the Laboratory for Laser Energetics, and the High Energy Density (HED) instrument at the European XFEL. Calibrated from the same ring positions on a single planar detector, HEXRD and the independent code pyFAI predict the same scattering angle 2$θ$ to numerical precision. On a dual-source dataset from the NIF, calibrating the detectors against both X-ray sources at once fits the rings of both to an RMS of 0.18° in 2$θ$, about one image-plate pixel, whereas a fit to either source alone, with the plate tilts held at their nominal values, fits its own rings nearly as well but mispredicts the other's by about 0.6°. The software is freely available under a BSD license.

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Patrick Avery, Joel V. Bernier, Brianna Major, Saransh Singh. 2026-10-18. HEXRD and HEXRDGUI: a flexible toolkit for X-ray diffraction analysis in dynamic compression experiments. https://arxiv.org/abs/2610.24989

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