Laser and Particle Beams

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Laser and Particle Beams (2009), 27:185-190 Cambridge University Press
Copyright © Cambridge University Press 2009
doi:10.1017/S0263034609000251

Research Article

Investigation of stimulated Raman scattering using a short-pulse diffraction limited laser beam near the instability threshold


J.L. Klinea1 c1, D.S. Montgomerya1, C. Rousseauxa2, S.D. Batona3, V. Tassina2, R.A. Hardina4, K.A. Flippoa1, R.P. Johnsona1, T. Shimadaa1, L. Yina1, B.J. Albrighta1, H.A. Rosea1 and F. Amiranoffa3

a1 Los Alamos National Laboratory, Los Alamos, New Mexico
a2 Commissariat à l'Energie Atomique, CEA, DAM, DIF, Arpajon, France
a3 LULI, UMR 7605, CNRS-CEA-Ecole Polytechnique-Université Paris VI, Ecole Polytechnique, Palaiseau, France
a4 West Virginia University, Morgantown, West Virginia
Article author query
kline jl [Google Scholar]
montgomery ds [Google Scholar]
rousseaux c [Google Scholar]
baton sd [Google Scholar]
tassin v [Google Scholar]
hardin ra [Google Scholar]
flippo ka [Google Scholar]
johnson rp [Google Scholar]
shimada t [Google Scholar]
yin l [Google Scholar]
albright bj [Google Scholar]
rose ha [Google Scholar]
amiranoff f [Google Scholar]

Abstract

Short pulse laser plasma interaction experiments using diffraction limited beams provide an excellent platform to investigate the fundamental physics of stimulated Raman scattering. Detailed understanding of these laser plasma instabilities impacts the current inertial confinement fusion ignition designs and could potentially impact fast ignition when higher energy lasers are used with longer pulse durations (>1 kJ and >1 ps). Using short laser pulses, experiments can be modeled over the entire interaction time of the laser using particle-in-cell codes to validate our understanding quantitatively. Experiments have been conducted at the Trident laser facility and the Laboratoire pour l'Utilisation des Lasers Intenses (LULI) to investigate stimulated Raman scattering near the threshold of the instability using 527 nm and 1059 nm laser light, respectively, with 1.5–3.0 ps pulses. In both experiments, the interaction beam was focused into pre-ionized helium gas-jet plasma. Measurements of the reflectivity as a function of intensity and kλD were completed at the Trident laser facility, where k is the electron plasma wave number and λD is the plasma Debye length. At LULI, a 300 fs Thomson scattering probe is used to directly measure the density fluctuations of the driven electron plasma and ion acoustic waves. Work is currently underway comparing the results of the experiments with simulations using the VPIC particle-in-cell code. Details of the experimental results are presented in this manuscript.

(Received October 17 2008)

(Accepted December 12 2008)

KeywordsNonlinear kinetic plasma effects; Raman scattering; Short pulse laser beams

Correspondence:

c1 Address correspondence and reprint requests to: John Kline, P-24, Plasma Physics, MS: E526, Los Alamos National Laboratory, Los Alamos, NM 87545. E-mail: jkline@lanl.gov