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arXiv · 2408.09329

Application of the Variational R-matrix Method for the Dirac Equation to the Be Atom

Chris H. Greene·Miguel A. Alarcón
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Abstract

This paper presents an implementation of the non-iterative eigenchannel R-matrix method for the Dirac equation. It includes a brief introduction, implementation details, and results for the photoionization cross-section of the beryllium atom. Beryllium is a convenient test due to small but significant relativistic effects. The current calculation aligns with other R-matrix calculations and experiments. It observes the change in the Fano line shape of the (2pnd)1P series and, reveals a previously unnoticed coupling between triplet and singlet series observable in the ground state photoionization cross-section.

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Chris H. Greene, Miguel A. Alarcón. 2024-08-18. Application of the Variational R-matrix Method for the Dirac Equation to the Be Atom. https://doi.org/10.1103/physreva.110.042825

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