HYBRID PARTICLE-IN-CELL SIMULATIONS OF STIMULATED BRILLOUIN-SCATTERING INCLUDING ION-ION COLLISIONS

It is shown that ion-ion collisions can have a very important effect o n stimulated Brillouin scattering of laser light in high-Z plasmas, su ch as those near the wall of a laser-irradiated hohlraum. We report th e first hybrid particle-in-cell simulations of stimulated Brillouin sc attering including these collisions. Collisions can play a vital role in the nonlinear state by maintaining a negative slope to the ion dist ribution function, which greatly distorts and even flattens near the i on wave phase velocity in collisionless simulations. Other collisional effects are also illustrated.