3D ray-tracing package dedicated to the irradiation study of a directly driven inertial confinement fusion capsule

Abstract

The compression of a directly driven all-DT capsule has been simulated by the hydrodynamic code Multi1D. The capsule absorbs a total energy of about 100 kJ allowing for a maximum density of 650 g/cm3 and a maximum confinement parameter ρR of 1.6 g/cm2. An ad-hoc 3D ray-tracing package has been developed to evaluate the uniformity of the deposition energy provided by the direct irradiation of the capsule. Two irradiation configurations with 32 and 48 laser beams characterized by a super-gaussian intensity profile have been considered. A robustness study has been performed as a function of the power imbalance. Neglecting any pointing errors and taking into account only for the power imbalance it is found that half of the shots performed with the two configurations provide the same irradiation uniformity. The 3D ray-tracing package has been also used to estimate the direct irradiation of a re-entrant cone inserted into the capsule. It is found that the direct irradiation of the cone surface reach a maximum intensity of 3 1014 W/cm2. © 2010 IOP Publishing Ltd.