A Detailed Configuration Accounting for the Hot Plasma Bound-Free Opacity Calculation

Alina Nadezhkina; Mikhail Vronskiy

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arXiv · 2508.11815

A Detailed Configuration Accounting for the Hot Plasma Bound-Free Opacity Calculation

Alina Nadezhkina·Mikhail Vronskiy

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Abstract

The calculation of the hot plasma bound-free opacity according to the average atom models often leads to a noticeable effect of initial configuration on the shell ionization threshold. For the related problem of taking into account the impact of configurations while calculating bound-bound opacity, G. Hazak and Y. Kurzweil developed a method within the Super Transition Arrays approach. Fourier transform method is the adaptation of their method for a Detailed Configurations Accounting. The bound--free opacity coefficient qualitative behavior makes it somewhat difficult to construct a direct analogue of Fourier transform method of Detailed Configurations Accounting for its calculation. We use the probabilistic reformulation of the method to obtain the expressions for the bound--free opacity coefficient that take into account the spread of ionization thresholds due to the shell occupation numbers fluctuations.

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Alina Nadezhkina, Mikhail Vronskiy. 2025-08-15. A Detailed Configuration Accounting for the Hot Plasma Bound-Free Opacity Calculation. https://arxiv.org/abs/2508.11815

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