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arXiv · 2110.11366

Axial-vector exchange contribution to the Hyperfine Splitting

Alejandro Miranda·Pablo Roig·Pablo Sanchez-Puertas
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Abstract

We revisit the contribution of axial-vector mesons to the hyperfine splitting of muonic hydrogen. We focus our attention on the doubly-virtual asymptotic behavior of the relevant form factors of axial-vector mesons, together with their coupling to nucleons based on resonance saturation and short-distance constraints. Among others, we find significant differences with respect to previous studies, including an opposite sign and a $\sim50\%$ effect of the doubly-virtual high-energy behavior.

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Alejandro Miranda, Pablo Roig, Pablo Sanchez-Puertas. 2021-10-21. Axial-vector exchange contribution to the Hyperfine Splitting. https://doi.org/10.1103/physrevd.105.016017

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