Effects of plasma interpenetration on hohlraum stagnation

Understanding plasma stagnation in laser-driven hohlraums is important for optimizing inertial confinement fusion experiments. It has been realized that single-species-averaged hydrodynamic codes are incapable of modelling this phenomenon, as they overlook the ion kinetic process and multi-fluid effects, leading to discrepancies between simulations and experimental results. A number of mechanisms that play important roles in these non-hydrodynamic processes but are missing in hydrodynamic simulations have been identified, including ion interpenetration and diffusion. To explore these important phenomena, observations made with various diagnostic techniques at Omega such as proton radiography and x-ray imaging are compared with modified three-dimensional hydrodynamic simulations, providing insight into the effects of plasma interpenetration on hohlraum stagnation and a more complete physical picture of hohlraum dynamics.

The work described herein was performed in part at the LLE National Laser User’s Facility (NLUF), and was supported in part by US DOE, LLNL and LLE.