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arXiv · 2110.13279

Three-Loop Corrections to Lamb Shift in Muonium and Positronium

Michael I. Eides·Valery A. Shelyuto
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Abstract

We calculate hard spin-independent three-loop radiative corrections to energy levels in muonium and positronium which are due to radiative insertions in two-photon exchange diagrams. These corrections could be relevant for the new generation of precise $1S-2S$ and $2S-2P$ measurements in muonium and positronium.

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Michael I. Eides, Valery A. Shelyuto. 2021-10-25. Three-Loop Corrections to Lamb Shift in Muonium and Positronium. https://doi.org/10.1103/physreva.105.012803

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