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arXiv · 2512.15288

Bound-electron self-energy calculations in Feynman and Coulomb gauges: detailed analysis

M. A. Reiter·E. O. Lazarev·D. A. Glazov·A. V. Malyshev·A. V. Volotka
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Abstract

The energy correction associated with the self-energy diagram is the leading (in magnitude) and fundamental (in significance) contribution to the Lamb shift in highly charged ions. Conventional approaches to this correction rely on partial-wave expansions, which is a stumbling block limiting accuracy. To elucidate the issue, we perform a comprehensive comparative analysis of partial-wave-expansion convergence between two gauges: Feynman and Coulomb. Some tricks for improving the convergence are discussed as well.

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M. A. Reiter, E. O. Lazarev, D. A. Glazov, A. V. Malyshev, A. V. Volotka. 2025-12-17. Bound-electron self-energy calculations in Feynman and Coulomb gauges: detailed analysis. https://arxiv.org/abs/2512.15288

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