EFFECT OF FILAMENTATION OF BRILLOUIN-SCATTERING IN LARGE UNDERDENSE PLASMAS IRRADIATED BY INCOHERENT LASER-LIGHT

An experimental study of stimulated Brillouin backscatter (B-SBS), produced in a large ''homogeneous'' underdense plasma using induced spatially incoherent laser light, is presented. The observations reveal that a strong correlation exists between the level of B-SBS and laser filamentation. It is suggested that a filamentory model of B-SBS is needed to better describe the scattering process under conditions of high laser irradiance and large plasma scale lengths.