Experimental observation of the Langmuir decay instability associated with the stimulated Raman scattering

An experiment is performed which definitely demonstrates the occurrence of the Langmuir decay instability in the laser plasma interaction. Stimulated Raman scattering is used as a source of well-defined electron plasma waves. Both products of the instability are observed simultaneously using Thomson scattering of a short wavelength probe beam. Resolution of the Thomson scattering measurements in wavelength, wavenumber, time and space allow an unambiguous identification of the ion acoustic waves. Spatial and temporal correlation of these ion acoustic waves with the stimulated Raman scattering activity is observed whereas they appear to be anticorrelated in time and space with the stimulated Brillouin scattering activity.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.