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arXiv · 2306.07748

Two-Loop Electron Factor Contribution to Lamb Shift in Muonium and Positronium

Michael I. Eides·Valery A. Shelyuto
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Abstract

We calculate hard spin-independent contributions to energy levels in muonium and positronium which are due to radiatively corrected electron factor insertion in two-photon exchange diagrams. Calculation of these corrections is motivated by the new round of precise measurements of spin-independent transition frequencies in muonium and positronium.

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Michael I. Eides, Valery A. Shelyuto. 2023-06-13. Two-Loop Electron Factor Contribution to Lamb Shift in Muonium and Positronium. https://doi.org/10.1016/j.physletb.2023.138087

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