Impact of Spatiotemporal Smoothing on the Two-Plasmon-Decay Instability

ORAL

Abstract

Higher levels of hot electrons from the two-plasmon-decay instability are observed when smoothing by spectral dispersion (SSD) is turned off in directly driven inertial confinement fusion experiments at the Omega Laser Facility. This finding is explained using a hot-spot model based on speckle statistics and simulation results from the laser-plasma simulation environment. The model accurately reproduces the relative increase in hot-electron activity at two different drive intensities, although it slightly overestimates the absolute number of hot electrons in all cases. Extrapolating from the current 360-GHz system while adhering to the logic of the hot-spot model suggests that larger SSD bandwidth should significantly mitigate hot-electron generation, and legacy 1-THz OMEGA experiments appear to support this conclusion. These results demonstrate that it is essential to account for laser speckles and spatiotemporal smoothing to obtain quantitative agreement with experiments.

*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

  • David Turnbull

    • Laboratory for Laser Energetics, U. of Rochester

  • Andrei Maximov

    • Laboratory for Laser Energetics, U. of Rochester

  • D. Cao

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

  • A.R. Christopherson

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

  • Dana Edgell

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

  • Russell Follett

    • University of Rochester
    • Laboratory for Laser Energetics, U. of Rochester
    • Laboratory for Laser Energetics, University of Rochester, Rochester, NY 14623
    • Laboratory for Laser Energetics

  • V. Gopalaswamy

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

  • James Knauer

    • Laboratory for Laser Energetics, U. of Rochester
    • 4Laboratory for Laser Energetics
    • Laboratory for Laser Energetics
    • LLE-UR
    • University of Rochester
    • Lab for Laser Energetics

  • J.P. Palastro

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

  • A. Shvydky

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

  • C. Stoeckl

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

  • Han Wen

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

  • D.H. Froula

    • Laboratory for Laser Energetics, U. of Rochester
    • Laboratory for Laser Energetics
    • Laboratory for Laser Energetics, University of Rochester
    • Laboratory for Laser Energetics University of Rochester
    • University of Rochester, Laboratory for Laser Energetics, Rochester, New York 14623, USA