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Title: Direct observation of the two-plasmon-decay common plasma wave using ultraviolet Thomson scattering

A 263-nm Thomson-scattering beam was used to directly probe two-plasmon-decay (TPD) excited electron plasma waves (EPWs) driven by between two and five 351-nm beams on the OMEGA Laser System. The amplitude of these waves was nearly independent of the number of drive beams at constant overlapped intensity, showing that the observed EPWs are common to the multiple beams. In an experimental configuration where the Thomson-scattering diagnostic was not wave matched to the common TPD EPWs, a broad spectrum of TPD-driven EPWs was observed, indicative of nonlinear effects associated with TPD saturation. Electron plasma waves corresponding to Langmuir decay of TPD EPWs were observed in both Thomson-scattering spectra, suggesting the Langmuir decay instability as a TPD saturation mechanism. Simulated Thomson-scattering spectra from three-dimensional numerical solutions of the extended Zakharov equations of TPD are in excellent agreement with the experimental spectra and verify the presence of the Langmuir decay instability.
Authors:
 [1] ;  [2] ;  [2] ;  [2] ;  [2] ;  [2] ;  [2] ;  [2] ;  [1]
  1. Univ. of Rochester, Rochester, NY (United States). Lab. for Laser Energetics and Dept. of Physics and Astronomy.
  2. Univ. of Rochester, Rochester, NY (United States). Lab. for Laser Energetics.
Publication Date:
OSTI Identifier:
1178088
DOE Contract Number:
NA0001944
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics (Print); Journal Volume: 91; Journal Issue: 3
Publisher:
American Physical Society (APS)
Research Org:
Univ. of Rochester, Rochester, NY (United States). Lab. for Laser Energetics.
Sponsoring Org:
USDOE
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY