Non-Maxwellian electron distributions in time-dependent simulations of low-Z materials illuminated by a high-intensity X-ray laser

作者：de la Varga Alberto G^*; Velarde Pedro; de Gaufridy Francois; Portillo David; Cotelo Manuel; Barbas Alfonso; Gonzalez Agustin; Zeitoun Philippe

来源：High Energy Density Physics, 2013, 9(3): 542-547.

DOI：10.1016/j.hedp.2013.05.010

• Non-Maxwellian electron distribution
• Non-LTE
• Time-dependent atomic kinetics

The interaction of high intensity X-ray lasers with matter is modeled. A collisional-radiative time-dependent module is implemented to study radiation transport in matter from ultrashort and ultra-intense X-ray bursts. Inverse bremsstrahlung absorption by free electrons, electron conduction or hydrodynamic effects are not considered. The collisional-radiative system is coupled with the electron distribution evolution treated with a Fokker-Planck approach with additional inelastic terms. The model includes spontaneous emission, resonant photoabsorption, collisional excitation and de-excitation, radiative recombination, photoionization, collisional ionization, three-body recombination, auto-ionization and dielectronic capture. It is found that for high densities, but still below solid, collisions play an important role and thermalization times are not short enough to ensure a thermal electron distribution. At these densities Maxwellian and non-Maxwellian electron distribution models yield substantial differences in collisional rates, modifying the atomic population dynamics.

• 出版日期2013-9