NONLINEAR PROCESSES FROM INTERACTION OF 1.053μmLASER WITH HOHLRAUM TARGETS

Abundant nonlinear processes may be producd in submillimeter size hohlraumtargets by 1.053μm laser light with duration of 1ns and energy of 300～600J.In experiments,Stimulated Brillouin Scattering(SBS)and Stimulated Raman Scattering(SRS)were directly meas-ured, and Resonance Absorption(RA),Two Plasmon Decay(TPD),and Ion Acoustic Decay(IAD)were observed indirectly.The experimental results show that SBS and SRS are the domi-nant nonlinear processes in cavity,they can scatter about 40% of the incident laser energy. Elec-tron plasma wave stimulated by nonlinear processes such as SRS, TPD,RA,and IAD is thesources of suprathermal electron generation. Our research indicates that SRS is the chief processfor electron plasma wave generation in hohlraum target,and it can produce suprathermalelectrons with a total energy about 10% of incident laser energy.Because spectra of nonlinearprocesses scattering light have a closely ralation with plasma state.We can obtain imformationabout plasma state through intensive measure and analysis to thesc spectra of scattering light.