EXAFS for probing thermal states of compressed materials at NIF

ORAL

Abstract



EXAFS (Extended X-ray Absorption Fine Structure) refers to the oscillatory modulations in x-ray absorption spectra above an absorption edge, generated by interference between photoelectron waves and scattering by neighbor atoms. EXAFS is sensitive to temperature of materials in the range of 100-10000K because ionic thermal motion reduces the coherence of the interference, leading to decay of the modulations. This talk will give a brief overview of the EXAFS platform at NIF, including development of a bright continuum backlighter [1], a high-resolution spectrometer [2], and a novel shape of crystal to achieve both high throughput and high resolution [3]. Excellent EXAFS data at K-edge have been obtained for Fe compressed up to 8 Mbar and Cu up to 10 Mbar. The EXAFS measurements at L-edge are more challenging due to smaller EXAFS amplitude. The high x-ray flux at NIF has enabled L-edge measurements for higher-Z materials such as Ta and Pb. The prospect of such a new capability at NIF for probing thermal states of compressed materials will be discussed.

*This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

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Publication: [1] A. Krygier, et al. App. Phys. Lett. 117, 251106 (2020).
[2] S. Stoupin, et al. Rev. Sci. Instrum. 92, 053102 (2021).
[3] N.A. Pablant, et al. Rev. Sci. Instrum. 92, 093904 (2021).

Presenters

  • Yuan Ping

    • Lawrence Livermore Natl Lab

Authors

  • Yuan Ping

    • Lawrence Livermore Natl Lab

  • Hong W Sio

    • Lawrence Livermore Natl Lab

  • Andrew Krygier

    • Lawrence Livermore National Laboratory

  • Dave Braun

    • Lawrence Livermore National Laboratory

  • Robert E Rudd

    • Lawrence Livermore Natl Lab

  • Stanimir Bonev

    • Lawrence Livermore National Laboratory

  • Amy L Coleman

    • Lawrence Livermore Natl Lab

  • Federica Coppari

    • Lawrence Livermore Natl Lab

  • David K Bradley

    • Lawrence Livermore Natl Lab

  • Jon H Eggert

    • Lawrence Livermore Natl Lab

  • Dayne E Fratanduono

    • Lawrence Livermore Natl Lab

  • Warren W Hsing

    • Lawrence Livermore Natl Lab

  • Gregory E Kemp

    • Lawrence Livermore National Laboratory
    • LLNL
    • Lawrence Livermore Natl Lab

  • Bernard Kozioziemski

    • Lawrence Livermore Natl Lab
    • LLNL

  • Thomas E Lockard

    • Lawrence Livermore Natl Lab

  • Andy J Mackinnon

    • Lawrence Livermore Natl Lab
    • Lawrence Livermore National Laboratory
    • LLNL
    • Lawrence Livermore National Lab

  • James M McNaney

    • Lawrence Livermore Natl Lab

  • Marius Millot

    • Lawrence Livermore Natl Lab

  • Neil Ose

    • Lawrence Livermore National Laboratory
    • Lawrence Livermore Natl Lab

  • Hye-Sook Park

    • Lawrence Livermore Natl Lab
    • LLNL

  • Marilyn B Schneider

    • Lawrence Livermore Natl Lab
    • LLNL

  • Stanislav Stoupin

    • Lawrence Livermore National Laboratory
    • LLNL

  • Manfred L Bitter

    • Princeton Plasma Physics Laboratory

  • Philip C Efthimion

    • Princeton Plasma Physics Laboratory
    • PPPL

  • Lan Gao

    • PPPL
    • Princeton Plasma Physics Laboratory

  • Kenneth W Hill

    • Princeton University

  • Brooklyn Frances Kraus

    • Princeton Plasma Physics Laboratory
    • PPPL

  • Novimir A Pablant

    • Princeton Plasma Physics Laboratory
    • PPPL
    • PPPL, Princeton University, P.O. Box 451, Princeton, New Jersey 08543, USA