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.

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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