INTENSITY SCALING OF STIMULATED RAMAN FORWARD SCATTERING IN LASER-PRODUCED PLASMAS

Measurement of the intensity scaling of stimulated Raman forward scattering (SRFS) at one observation angle is presented. A single, high-intensity 527-nm laser beam excited the instability in a preformed plasma whose properties are such that the predicted gain for SRFS spans the range anticipated for high-gain laser-fusion experiments. At low intensities, the gain of the instability was consistent with convective theory. At intensities greater than 1 X 10(15) W/cm2, the instability saturated at a level of less than 10(11) W/sr nm cm2.