Finite Ion-Relaxation and Nonequilibrium Radiation Effects on Laser-Driven Implosions

Abstract

The implosion dynamics of recent experiments with high-aspect ratio laser-driven targets are re-examined by taking account of finite mean free paths of the ion. The mean free path is found to be comparable to the fuel size and this can cause a significant departure from a fluid-like description. One of such effects stemming from the finite mean free path of the ion, real viscosity, seriously changes the results; the compression ratio becomes 5 times smaller with this real viscosity. In addition to this, the inclusion of a non-LTE (local thermodynamic equilibrium) atomic process is shown to critically determine the implosion dynamics.