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.

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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