Modeling of the He-like magnesium spectral lines radiation from the plasma created by XeCl and Nd-glass lasers

Resonant and intercombination spectral line formation of He-like magnesium is analyzed both experimentally and numerically. Simulations of the laser-produced plasma evolution in ID approximation made using the code GIDRA show fairly good agreement with experimental data both close and far from the target. It is shown that in plasma created by XeCl laser at flux density 8 x 1012 W/cm2 the peak of electron temperature is placed downstream from the critical surface at density significantly smaller than critical, and radiation in both resonant and recombination lines is also produced by the plasma region with density below critical. Simulations also show significant line radiation at large distances (1-2 mm) from the target as it was observed in experiments. This secondary peak is produced by a compression wave forming near the plasma front. In contrast, radiation in these lines in plasma created by Nd-glass laser at flux density 5 x 1013 W/cm2 comes from the plasma region placed deeper than the critical surface and has no tail at large distances. Spectral line radiation reabsorbtion in the plasma was found to be responsible for the observed relative intensity of the resonant and intercombination lines.