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arXiv · 2104.00551

Time-Dependent Density Functional Theory Applied to Average Atom Opacity

N. M. Gill·C. J. Fontes·C. E. Starrett
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Abstract

We focus on studying the opacity of iron, chromium, and nickel plasmas at conditions relevant to experiments carried out at Sandia National Laboratories [J. E. Bailey et al., Nature 517, 56 (2015)]. We calculate the photo-absorption cross-sections and subsequent opacity for plasmas using linear response time-dependent density functional theory (TD-DFT). Our results indicate that the physics of channel mixing accounted for in linear response TD-DFT leads to an increase in the opacity in the bound-free quasi-continuum, where the Sandia experiments indicate that models under-predict iron opacity. However, the increase seen in our calculations is only in the range of 5-10%. Further, we do not see any change in this trend for chromium and nickel. This behavior indicates that channel mixing effects do not explain the trends in opacity observed in the Sandia experiments.

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N. M. Gill, C. J. Fontes, C. E. Starrett. 2021-01-21. Time-Dependent Density Functional Theory Applied to Average Atom Opacity. https://doi.org/10.1103/physreve.103.043206

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