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Photoionization of the Li atom: Convergent-close-coupling calculations with a focus on two-electron removal

Alfred Müller ^*

Anatoli S. Kheifets

Igor Bray and Dmitry V. Fursa

I. Physikalisches Institut, Justus-Liebig-Universität Gießen, 35392 Giessen, Germany

Research School of Physics, The Australian National University, Canberra, ACT 2601, Australia

Department of Physics and Astronomy, Curtin University, Perth, WA 6102, Australia

^*Contact author: Alfred.Mueller@physik.jlug.de

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Phys. Rev. A 113, 033105 – Published 9 March, 2026

DOI: https://doi.org/10.1103/l4xt-3sxy

Abstract

In a combined experimental and theoretical study, Müller et al. [Phys. Rev. A 111, 053108 (2025)] revealed highly detailed resonant structure in ionization with excitation and in double ionization of the Li-like $B^{2 +}$ ion. That work demonstrated the strong predictive power of the convergent-close-coupling (CCC) method when enhanced by modern supercomputing technology. In the present work, we apply CCC to analogous ionization processes in the Li atom. Again, we find $K$ -shell ionization accompanied by $K$ -shell excitation to contribute relatively strongly to the double photoionization of three-electron Li. Comprehensive detailed comparisons with the existing experimental data are presented and discussed.

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References (77)

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Phys. Rev. A 113, 033105– Published 9 March, 2026

Vol. 113, Iss. 3 — March 2026

Received 17 December 2025
Accepted 17 February 2026

DOI: https://doi.org/10.1103/l4xt-3sxy

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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Photoionization of the Li atom: Convergent-close-coupling calculations with a focus on two-electron removal

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