Data driven models of the performance and repeatability of NIF high foot implosions

ORAL

Abstract

Recent high foot (HF) inertial confinement fusion (ICF) experiments performed at the national ignition facility (NIF) have consisted of enough laser shots that a data-driven analysis of capsule performance is feasible. In this work we use 20-30 individual implosions of similar design, spanning laser drive energies from 1.2 to 1.8 MJ, to quantify our current understanding of the behavior of HF ICF implosions. We develop a probabilistic model for the projected performance of a given implosion and use it to quantify uncertainties in predicted performance including shot-shot variations and observation uncertainties. We investigate the statistical significance of the observed performance differences between different laser pulse shapes, ablator materials, and capsule designs. Finally, using a cross-validation technique, we demonstrate that 5-10 repeated shots of a similar design are required before real trends in the data can be distinguished from shot-shot variations.

*This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. LLNL-ABS-674957

Authors

  • J. Gaffney

    • Lawrence Livermore National Laboratory
    • LLNL
  • Dan Casey

    • Lawrence Livermore National Laboratory
  • Debbie Callahan

    • Lawrence Livermore National Laboratory
  • Ed Hartouni

    • Lawrence Livermore National Laboratory
  • Tammy Ma

    • Lawrence Livermore National Laboratory
  • Brian Spears

    • Lawrence Livermore National Laboratory