Extended X-ray Absorption Fine Structure Temperature Analysis at High-Energy-Density Conditions

ORAL

Abstract

A critical next step in understanding high-energy-density (HED) matter is to characterize the temperature of materials at HED conditions. Temperature measurements are historically difficult at low temperature HED conditions (above 100 GPa and below 5000 K) and extended x-ray absorption fine structure (EXAFS) spectroscopy is one of the few experimental techniques capable of constraining temperature at these conditions by measuring the variation in the distances between neighboring atoms. A variety of synthetic and experimental EXAFS spectra of iron, nickel and invar (Fe64Ni36) were analyzed with a Bayesian inference routine to infer the atom positions using both a cumulant expansion and a parametrized ion-distribution model. The parametrized ion-distribution model was found to improve the constraint on the true ion distribution for the synthetic asymmetric systems. These ion distributions were ultimately related to the temperature of the compressed sample using a variety of models that will be discussed herein.

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Publication: D.A. Chin et al., Parametrized ion-distribution model for extended x-ray absorption fine-structure analysis at high-energy-density conditions Phys. Plasmas 31, 042708 (2024) https://doi.org/10.1063/5.0191549

Presenters

  • D. A. Alexander Chin

    University of Rochester, Laboratory for Laser Energetics

Authors

  • D. A. Alexander Chin

    University of Rochester, Laboratory for Laser Energetics

  • Matthew Edward Signor

    University of Rochester, Laboratory for Laser Energetics, University of Rochester

  • David T Bishel

    University of Rochester

  • Ethan A Smith

    University of Rochester, Laboratory for Laser Energetics, University of Rochester

  • Philip M Nilson

    Lab for Laser Energetics

  • James Ryan Rygg

    Dept. of Mechanical Engg, Dept. of Physics and Astronomy, University of Rochester. Laboratory for Laser Energy, Rochester, NY, USA.

  • Gilbert W Collins

    Laboratory for Laser Energetics, University of Rochester, Laboratory for Laser Energetics, University of Rochester

  • Silvia Boccato

    Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, Sorbonne Université, Muséum National d'Histoire Naturelle

  • Raffaella Torchio

    ESRF

  • Federica Coppari

    Lawrence Livermore Natl Lab

  • Yuan Ping

    Lawrence Livermore National Laboratory, Lawrence Livermore Natl Lab

  • Maitrayee Ghosh

    University of Rochester

  • John J Ruby

    Department of Mechanical Engineering, University of Rochester

  • Grant B Bunker

    Illinois Institute of Technology

  • Danae N Polsin

    Laboratory for Laser Energetics