OBSERVATIONS OF TRANSITION TO STRONGLY COUPLED STIMULATED BRILLOUIN-SCATTERING IN LASER-PLASMA INTERACTIONS

Scattered light near the laser wavelength has been spectrally and temp orally resolved in experiments in which a 1.06 mu m wavelength laser i rradiates a low-Z target. At sufficiently high laser intensities, the backscattered spectrum broadens toward longer wavelengths (lower frequ encies) by an amount which is several times an ion acoustic shift. The behavior of the spectra agrees well with the prediction of time-depen dent, homogeneous theory.