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arXiv · 2607.21238

Plasma screening and configuration interaction effects induced large enhancement on L-shell photoionization cross sections and opacity

Fuyang Zhou·Shengbo Niu·Simei Lu·Chuangying Li·Xiang Gao·Yong Wu·Yizhi Qu·Jianguo Wang
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Abstract

An opacity model that incorporates improved treatments of both plasma screening and configuration interaction (CI) effects is proposed, and a 25-30% enhancement on the iron L-shell opacity is predicted at solar interior temperatures. It is originated from the plasma screening induced 14-17% enhancement on the photoionization cross sections and the CI induced 10-20% enhancement on photoexcitation and photoionization cross sections for open L-shell ions. These explain the long-standing discrepancy between theoretical and experimental iron opacity [Nature 517, 56], and the relatively weaker enhancements on chromium and nickel opacity [Phys. Rev. Lett. 122, 235001] due to the sensitivity of these effects to the different L-shell electron population and plasma temperature/density. This letter provides the systematic interpretation of L-shell opacity measurements at solar interior temperatures, and advances the accurate simulation of opacity and radiative transport in high-energy-density plasma.

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Fuyang Zhou, Shengbo Niu, Simei Lu, Chuangying Li, Xiang Gao, Yong Wu, Yizhi Qu, Jianguo Wang. 2026-07-23. Plasma screening and configuration interaction effects induced large enhancement on L-shell photoionization cross sections and opacity. https://arxiv.org/abs/2607.21238

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