Reproducibility of NIF hohlraum measurements

ORAL

Abstract

The strategy of experimentally ``tuning'' the implosion in a NIF hohlraum ignition target towards increasing hot-spot pressure, areal density of compressed fuel, and neutron yield relies on a level of experimental reproducibility. We examine the reproducibility of experimental measurements for a collection of 15 identical NIF hohlraum experiments. The measurements include incident laser power, backscattered optical power, x-ray measurements, hot-electron fraction and energy, and target characteristics. We use exact statistics to set 1-sigma confidence levels on the variations in each of the measurements. Of particular interest is the backscatter and laser-induced hot-spot locations on the hohlraum wall. Hohlraum implosion designs typically include variability specifications [S. W. Haan, etal, Phys. Plasmas 18, 051001 (2011)]. We describe our findings and compare with the specifications.

*This work was performed under the auspices of the U.S. Department of Energy by University of California, Lawrence Livermore National Laboratory under Contract W-7405-Eng-48.

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Authors

  • John Moody

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

  • J.E. Ralph

    • Lawrence Livermore National Laboratory

  • D.P. Turnbull

    • Lawrence Livermore National Laboratory

  • D.T. Casey

    • Lawrence Livermore National Laboratory

  • F. Albert

    • Lawrence Livermore National Laboratory

  • B.L. Bachmann

    • Lawrence Livermore National Laboratory

  • T. Doeppner

    • Lawrence Livermore National Laboratory

  • L. Divol

    • Lawrence Livermore National Laboratory

  • G.P. Grim

    • Lawrence Livermore National Laboratory

  • M. Hoover

    • Lawrence Livermore National Laboratory

  • O.L. Landen

    • Lawrence Livermore National Laboratory

  • B.J. MacGowan

    • Lawrence Livermore National Laboratory

  • P.A. Michel

    • Lawrence Livermore National Laboratory

  • A.S. Moore

    • Lawrence Livermore National Laboratory

  • J.E. Pino

    • Lawrence Livermore National Laboratory

  • M.B. Schneider

    • Lawrence Livermore National Laboratory

  • R.E. Tipton

    • Lawrence Livermore National Laboratory

  • V.A. Smalyuk

    • Lawrence Livermore National Laboratory

  • D.J. Strozzi

    • Lawrence Livermore National Laboratory

  • K. Widmann

    • Lawrence Livermore National Laboratory

  • M. Hohenberger

    • Laboratory for Laser Energetics