Published online by Cambridge University Press: 09 March 2009
The behavior of the stimulated Raman scattering is investigated in a laser-irradiated plasma with an inhomogeneous density profile, by means of wave-coupling simulations. In the case of a regular hydrodynamic-like profile, a spectral broadening is observed when the laser irradiance is increased and is found to result from a coupling between the convective and the absolute Raman scattering, via pump depletion. In the case where a short-scale modulation of the density is superimposed on the profile, the spectrum is strongly influenced by the propagation velocity of the modulation and by the sinusoidal/chaotic nature of the modulation.