Laser-Absorption Profile Measurements on OMEGA to Verify Cross-Beam Energy Transfer Mitigation Using a Variable Wavelength Beam

ORAL

Abstract

A variable wavelength beam (TOP9) is being deployed on OMEGA to study cross-beam energy transfer (CBET) mitigation and increased absorption with wavelength detuning. Laser light scattered from a target is the most-direct measurement for diagnosing laser absorption in a direct-drive implosion. The beamlets diagnostic images unabsorbed light from all beams as distinct “spots” onto a gated optical imager. The intensity of each spot is a measure of the effective absorption for a light “beamlet” originating from a specific point on the beam profile, including CBET along its path. In symmetric‑drive implosions, CBET transfers energy from beamlets near the center of the beam profile to beamlets near the edge of the beam profile. CBET mitigation can be diagnosed by a change in the beamlet spot intensity pattern. The intensity of the TOP9 beamlet will be used to diagnose changes in absorption as the TOP9 wavelength varies.

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Presenters

  • Dana H Edgell

    University of Rochester Laboratory for Laser Energetics

Authors

  • Dana H Edgell

    University of Rochester Laboratory for Laser Energetics

  • Russell Follett

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

  • Joe Katz

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

  • John P. Palastro

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

  • David Turnbull

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

  • Dustin H Froula

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