A time-resolved spectroscopy study of the resonance-line emission in the Ge XXIII XUV laser

A comparison is presented of the temporally resolved resonance-line emission from the Ne-like Ge XUV laser (pumped with nanosecond pulses) with the predictions for the same emission from the hydro-atomic code EHYBRID. The specific lines chosen were the two 3s-2p Ne-like lines at 10.01 and 9.762 Angstrom, and the 3s-2p F-like group of lines in the 9.4-9.6 Angstrom region. Modification of the code to include 112 excited levels of the F-like ion facilitated a direct comparison between experiment and model of (i) the temporal variation of the emissions and (ii) the variation of the peak intensity ratios of the F-like to Ne-like emissions with irradiance on target. Agreement between experiment and model was generally good, with the trends of the F/Ne ratio variation with irradiance being clearly reproduced. The results show that the model is realistically simulating the hydrodynamics-and atomic kinetics of the plasma. This provides further support that the model can simultaneously calculate the Delta n = 1 (approximate to keV) and the Delta n = 0 (sub-keV) transition intensities through population dynamics which are acceptably accurate.