A computational study of x-ray emission from laser-irradiated Ge-doped foams

作者:Colvin Jeffrey D*; Fournier Kevin B; May Mark J; Scott Howard A
来源:Physics of Plasmas, 2010, 17(7): 073111.
DOI:10.1063/1.3460817

摘要

New advances in fabrication of low-density high-Z-doped foams have opened new windows on understanding how materials that are not in local thermodynamic equilibrium (LTE) are heated and radiate. Simulations are discussed in this paper of the x-ray spectral emissions from laser-irradiated very low-density Ge-doped silica aerogel targets using a two-dimensional radiation-hydrodynamics code incorporating a modern non-LTE superconfiguration atomic model. Details of the computational model are presented, and it is shown that, for the long-scale-length, subcritical-density, similar to 2-3 keV electron temperature plasmas created in experiments at the Omega laser facility [T. R. Boehly et al., Opt. Commun. 133, 495 (1997)], the simulations provide a close match to both the measured Ge L-shell emission (similar to 1-1.5 keV) and the measured Ge K-shell emission (similar to 10-11 keV), but only by accounting properly for nonlocal thermal conduction. The older average-atom atomic model is shown to be inadequate for these non-LTE plasmas. [doi:10.1063/1.3460817]

  • 出版日期2010-7