Efficient Raman Sidescatter and Hot-Electron Production in Laser-Plasma Interaction Experiments

These experiments studied the Raman instability occurring at densities below the quarter-critical density of the incident 0.53-\ensuremath{\mu}m laser light. Solid gold targets were irradiated by up to 4 kJ of energy in a 1-ns pulse with focal spots of 150 to 1880 \ensuremath{\mu}m. The angular distribution of the Raman scattering shows efficient Raman sidescatter. The energy in electron plasma waves accounts for the hot-electron production over almost three orders of magnitude. We report the results and discuss the implications for laser fusion.