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The second-order electron self-energy in hydrogen-like ions

I. Goidenko·L. Labzowsky·A. Nefiodov·G. Plunien·G. Soff
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Abstract

A calculation of the simplest part of the second-order electron self-energy (loop after loop irreducible contribution) for hydrogen-like ions with nuclear charge numbers $3 \leq Z \leq 92$ is presented. This serves as a test for the more complicated second-order self-energy parts (loop inside loop and crossed loop contributions) for heavy one-electron ions. Our results are in strong disagreement with recent calculations of Mallampalli and Sapirstein for low $Z$ values but are compatible with the two known terms of the analytical $Zα$-expansion.

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I. Goidenko, L. Labzowsky, A. Nefiodov, G. Plunien, G. Soff. 1999-04-08. The second-order electron self-energy in hydrogen-like ions. https://doi.org/10.1103/physrevlett.83.2312

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