Onset and saturation of the spectral intensity of stimulated brillouin scattering in inhomogeneous laser-produced plasmas

Measurements are reported of the spectral intensity of emissions attributed to stimulated Brillouin scattering (SBS) of 0.53 mu m laser light from an inhomogeneous CH plasma, at densities of interest to laser fusion or x-ray lasers. The onset of SBS confirms recent theory, and no dependence of the saturated spectral reflectivity on density or pump strength is seen. The total reflectivity, which reaches 15%, increases with the spectral width of the SBS. These quantitative data can test theory and simulations of saturation and also have implications for the National Ignition Facility.