X-ray emission and hydrodynamic expansion of plane carbon targets under the influence of high-intensity laser radiation

The response of a carbon slab to high-intensity laser irradiation is calculated using a plane 1-D hydrodynamics code. Partial ionization of the resultant plasma is calculated using local thermodynamic equilibrium, but radiation transport is treated independently by a multigroup S 2 method. Results, including expansion velocity and the conversion efficiency of laser light to X-rays, are presented for peak-power densities in the range 10 13 -10 16 W cm -2 and pulse durations of 100 ps-10 ns. The effects of laser wavelength and line emission are discussed and a criterion for the applicability of the LTE ionization model is given.