Influence of argon impurities on the elastic scattering of x-rays from imploding beryllium capsules

doi:10.1016/j.hedp.2018.02.003

Title: Influence of argon impurities on the elastic scattering of x-rays from imploding beryllium capsules

Abstract

Here, we investigate the effect of argon impurities on the elastic component of x-ray scattering spectra taken from directly driven beryllium capsule implosions at the OMEGA laser. The plasma conditions were obtained in a previous analysis [18] by fitting the inelastic scattering component. We show that the known argon impurity in the beryllium modifies the elastic scattering due to the larger number of bound electrons. We indeed find significant deviations in the elastic scattering from roughly 1 at.% argon contained in the beryllium. With knowledge of the argon impurity fraction, we use the elastic scattering component to determine the charge state of the compressed beryllium, as the fits are rather insensitive to the argon charge state. Lastly, we discuss how doping small fractions of mid- or high-Z elements into low-Z materials could allow ionization balance studies in dense plasmas.

Authors:

^[1]; Chapman, D. A. ^[2]; Kritcher, A. L. ^[3]; Schoff, M. ^[4];

^[4];

^[3]; Glenzer, S. H. ^[5]; Falcone, R. W. ^[1]; Gericke, D. O. ^[6]; Döppner, T. ^[3]

Univ. of California, Berkeley, CA (United States). Physics Department
AWE plc, Aldermaston, Reading (United Kingdom); University of Warwick (United Kingdom). Centre for Fusion, Space and Astrophysics, Department of Physics
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
General Atomics, San Diego, CA (United States)
SLAC National Accelerator Lab., Menlo Park, CA (United States)
University of Warwick (United Kingdom). Centre for Fusion, Space and Astrophysics, Department of Physics

Publication Date:: 2018-03-01

Research Org.:: Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

Sponsoring Org.:: USDOE Office of Science (SC), Fusion Energy Sciences (FES) (SC-24)

OSTI Identifier:: 1426137

Alternate Identifier(s):: OSTI ID: 1548686

Report Number(s):: LLNL-JRNL-742926
Journal ID: ISSN 1574-1818; TRN: US1802228

Grant/Contract Number:: AC52-07NA27344; SC0018298; NA0002135; AC52-06NA27279; 18-ERD-033

Resource Type:: Accepted Manuscript

Journal Name:: High Energy Density Physics

Additional Journal Information:: Journal Volume: 26; Journal Issue: C; Journal ID: ISSN 1574-1818

Publisher:: Elsevier

Country of Publication:: United States

Language:: English

Subject:: 42 ENGINEERING; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 36 MATERIALS SCIENCE; Warm-dense-matter; Dense plasmas; X-ray Thomson scattering; Ionization balance

Citation Formats


                    Saunders, A. M., Chapman, D. A., Kritcher, A. L., Schoff, M., Shuldberg, C., Landen, O. L., Glenzer, S. H., Falcone, R. W., Gericke, D. O., and Döppner, T. Influence of argon impurities on the elastic scattering of x-rays from imploding beryllium capsules.  United States: N. p., 2018. 
        Web.  doi:10.1016/j.hedp.2018.02.003.

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                    Saunders, A. M., Chapman, D. A., Kritcher, A. L., Schoff, M., Shuldberg, C., Landen, O. L., Glenzer, S. H., Falcone, R. W., Gericke, D. O., & Döppner, T. Influence of argon impurities on the elastic scattering of x-rays from imploding beryllium capsules.  United States.  doi:10.1016/j.hedp.2018.02.003.

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                    Saunders, A. M., Chapman, D. A., Kritcher, A. L., Schoff, M., Shuldberg, C., Landen, O. L., Glenzer, S. H., Falcone, R. W., Gericke, D. O., and Döppner, T. Thu .  
        "Influence of argon impurities on the elastic scattering of x-rays from imploding beryllium capsules".  United States.  doi:10.1016/j.hedp.2018.02.003.  https://www.osti.gov/servlets/purl/1426137.

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@article{osti_1426137,

  title        = {Influence of argon impurities on the elastic scattering of x-rays from imploding beryllium capsules},

  author       = {Saunders, A. M. and Chapman, D. A. and Kritcher, A. L. and Schoff, M. and Shuldberg, C. and Landen, O. L. and Glenzer, S. H. and Falcone, R. W. and Gericke, D. O. and Döppner, T.},

  abstractNote = {Here, we investigate the effect of argon impurities on the elastic component of x-ray scattering spectra taken from directly driven beryllium capsule implosions at the OMEGA laser. The plasma conditions were obtained in a previous analysis [18] by fitting the inelastic scattering component. We show that the known argon impurity in the beryllium modifies the elastic scattering due to the larger number of bound electrons. We indeed find significant deviations in the elastic scattering from roughly 1 at.% argon contained in the beryllium. With knowledge of the argon impurity fraction, we use the elastic scattering component to determine the charge state of the compressed beryllium, as the fits are rather insensitive to the argon charge state. Lastly, we discuss how doping small fractions of mid- or high-Z elements into low-Z materials could allow ionization balance studies in dense plasmas.},

  doi          = {10.1016/j.hedp.2018.02.003},

  journal      = {High Energy Density Physics},

  number       = C,

  volume       = 26,

  place        = {United States},

  year         = {2018},

  month        = {3}

}

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DOI: 10.1016/j.hedp.2018.02.003

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Figure 1: Experimental setup of the experiment as presented in Ref. [18]. The top shows the schematic of the experiment and images of the x-ray emission from the sample as it imploded. The bottom displays a photo of the cone-in-shell target as well as outputs from radiation-hydrodynamic modeling of themore »

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