Spherical ion kinetic simulations of DT implosions

The implosion of the DT plasma in an ablatively driven glass microballoon was simulated with a spherical ion kinetic code. The ion velocity distribution functions were strongly non-Maxwellian, and mostly depleted of fast ions. A high viscosity contributed to fuel heating, while large ion heat fluxes towards the pusher strongly cooled the fuel. This latter kinetic effect may explain in part why hydrodynamic simulations usually predict higher neutron yields than are measured.