Application of Thomson scattering to identify ion acoustic waves stimulated by the Langmuir decay instability

Journal Article · Fri Sep 01 04:00:00 EDT 2000 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.1288259· OSTI ID:20217546

Depierreux, S ^[1]; Labaune, C ^[1]; Fuchs, J ^[1]; Baldis, H A ^[2]

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1. Laboratoire pour l'Utilisation des Lasers Intenses, UMR n degree sign 7605, CNRS-Ecole Polytechnique CEA, Universite Paris VI, 91128 Palaiseau Cedex, (France)
2. Institute for Laser Science and Applications (ILSA), Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94550 (United States)

In this article, we present how ion acoustic waves can be unambiguously identified and can be used to definitely demonstrate the existence of the Langmuir decay instability (LDI) of electron plasma waves associated with stimulated Raman scattering. This observation is very important in the context of inertial confinement fusion because the LDI is a mechanism that may influence the stimulated Raman scattering saturation and growth. The experimental identification of those waves relies on Thomson scattering of a short wavelength probe beam. The Thomson scattered light was analyzed by two sets of spectrometer and streak camera providing information on the density fluctuations associated with the electron plasma waves and ion acoustic waves with temporal and spectral resolutions. Selection of a narrow range of angles (4 degree sign of aperture) inside the probe and scattered light apertures provided necessary resolution in wave vector. The method used for the design of the Thomson scattering diagnostic is described as well as the technique used to clearly identify the observed ion acoustic waves as one of the Langmuir decay instability products. (c) 2000 American Institute of Physics.

• OSTI ID: 20217546
• Journal Information: Review of Scientific Instruments, Journal Name: Review of Scientific Instruments Journal Issue: 9 Vol. 71; ISSN 0034-6748; ISSN RSINAK
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
EXPERIMENTAL DATA
ION ACOUSTIC WAVES
PLASMA DIAGNOSTICS
PLASMA INSTABILITY
PLASMA WAVES
THOMSON SCATTERING