Laser-plasma interactions in NIF ignition targets

Recent ignition point designs for achieving ignition in 2010 at the National Ignition Facility (NIF) have been developed at Lawrence Livermore National Laboratory. These four designs use approximately 1 MJ of input laser energy, have ``cocktail'' walls, and contain some combination of gas fill, liner, foam fill or shine shields in the interior of the target. An analysis of the laser-plasma interactions in these targets is presented. Levels of laser scatter and beam spray are estimated from post-processing radiation-hydrodynamics simulations of the various point designs. NIF beams propagating through the generated plasma blow-off of these designs will be simulated, using pF3D, to further quantify the degree of laser scatter and spray. The role of nonlinear saturation of laser scatter via wave-wave and wave-particle interactions will be addressed.