Feasibility Study of Measuring In-Flight Shell Thickness for a Laser-Direct-Drive DT Cryogenic Implosion

ORAL

Abstract

In laser-direct-drive (LDD) inertial confinement fusion (ICF) experiments, the hydrodynamic instabilities seeded by laser imprint and target features (e.g., microscopic surface debris, fill tube or stalk) can increase the in-flight shell thickness (i.e., decompress the shell) during the acceleration phase. Signatures from self-emission X rays versus the ablation front are investigated to diagnose the cryogenic layer, similar to what was done on warm LDD implosions of gas-filled, plastic shell targets [D.T. Michel et al., Phys. Rev. E 95, 051202(R) (2017)]. The feasibility of extending a diagnostic technique to obtain the in-flight shell thickness measurements of an LDD ICF DT cryogenic implosion from the spatial distribution of the X-ray emission will be presented for a range of adiabat, between 2 and 5. The shell trajectories are inferred by comparing the hydrodynamic profiles of the target with self-emission profiles obtained from a radiative transport post-processor, including the instrument response function of the X-ray imager.

*This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0003856.

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Authors

  • Joshua Baltazar

    • Laboratory for Laser Energetics, University of Rochester

  • Rahul Shah

    • University of Rochester Laboratory for Laser Energetics
    • Laboratory for Laser Energetics, U. of Rochester
    • Laboratory for Laser Energetics
    • Laboratory for Laser Energetics, University of Rochester
    • Lab for Laser Energetics
    • University of Rochester

  • Suxing Hu

    • Laboratory for Laser Energetics, Univ. of Rochester
    • Laboratory for Laser Energetics, University of Rochester
    • Laboratory for Laser Energetics, U. of Rochester
    • LLE
    • University of Rochester
    • Laboratory for Laser Energetics
    • Laboratory for Laser Energetics, Uni. of Rochester

  • K. Churnetski

    • Laboratory for Laser Energetics, U. of Rochester
    • Laboratory for Laser Energetics, University of Rochester

  • Reuben Epstein

    • Laboratory for Laser Energetics, University of Rochester
    • LLE, University of Rochester
    • Laboratory for Laser Energetics, U. of Rochester
    • Laboratory for Laser Energetics

  • Iogr Igumenshchev

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

  • T. Joshi

    • Laboratory for Laser Energetics, University of Rochester

  • Wolfgang Theobald

    • University of Rochester
    • Lab for Laser Energetics
    • Laboratory for Laser Energetics
    • LLE
    • LLE, Univ. of Rochester
    • Laboratory for Laser Energetics, U. of Rochester
    • Laboratory for Laser Energetics, University of Rochester

  • V. N. Goncharov

    • University of Rochester
    • Laboratory for Laser Energetics
    • LLE, Univ. of Rochester
    • Laboratory for Laser Energetics, University of Rochester

  • Sean Regan

    • University of Rochester
    • Laboratory for Laser Energetics - University of Rochester
    • Laboratory for Laser Energetics, U. of Rochester
    • Laboratory for Laser Energetics
    • LLE-UR
    • LLE, Univ. of Rochester
    • Laboratory for Laser Energetics, University of Rochester
    • Lab for Laser Energetics