Spectrum evolution of relativistically strong laser pulses during interaction with rarefied plasma

Using method of particles in a cell one carried out experimental study and numerical simulation of plasma wave overturning and time evolution of forced combination scattering backward at interaction of subpicosecond laser pulses with loose plasma. The experiment results demonstrate that deep modulations with clearly expressed symmetry whose nature depends on plasma density and on laser pulse intensity, appear in the spectrum of radiation scattered backward. Modulations and saturation of the forced combination scattering backward occur at similar intensities of laser radiation. 15 refs., 8 figs