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arXiv · 2602.15616

Relativistic nuclear recoil effects in hyperfine splitting of hydrogenic systems

Jakub Hevler·Andrzej Maroń·Krzysztof Pachucki
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Abstract

Finite nuclear mass $(Z\,\alpha)^2\,m/M\,E_F$ corrections to the hyperfine splitting in hydrogenic systems are calculated using a combined relativistic heavy particle and nonrelativistic quantum electrodynamics. The obtained results are in disagreement with previous calculations by Bodwin and Yennie [Phys. Rev. D {\bf 37}, 498 (1988)]. The comparison of improved theoretical predictions with the corresponding measurements in hydrogen reveals $2\,\sigma$ discrepancy, which may indicate problems with the proton structure corrections.

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Jakub Hevler, Andrzej Maroń, Krzysztof Pachucki. 2026-02-17. Relativistic nuclear recoil effects in hyperfine splitting of hydrogenic systems. https://arxiv.org/abs/2602.15616

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