LULI2000 - Laser-plasma interaction physics for ICF: Stimulated Raman Scattering in the kinetic regime and crossing beams effects in a 3-beam configuration (S. Depierreux)
The kJ nanosecond beam, the picosecond beam and the blue nanosecond beam are used to explore the interaction in long and hot underdense plasmas in the context of inertial confinement fusion. The important questions explored in this experiment concern the development of stimulated Raman Scattering (SRS) in the kinetic regime relevant of megajoule scale experiments and crossing beams effects on backscattering. Both subjects are explored with diagnostics set-up on the picosecond and nanosecond beams to measure the transmitted light and the backscattering and near backscattering in the Brillouin and Raman wavelengths range. The kinetic regime for SRS is reached by reducing the density in the interaction region while keeping the electron temperature at ~ 1 keV using underdense foams heated by the kJ nanosecond beam. The SRS backscattering is measured as a function of the laser duration and plasma parameters at different intensity levels. The electron plasma wave response will also be studied in a seeded experiment with a set-up adapted from our past nanosecond experiments. Finally, crossed beams effects on backscattering will be investigated for the interaction with the three beams.
LULI2000 : S10-S12 / 2016
co-PI : C. Labaune (LULI)