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arXiv · 2511.13097

On the Charm Contribution to the Muon $g-2$ Light-by-Light

Johan Bijnens·Nils Hermansson-Truedsson·Antonio Rodríguez-Sánchez
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Abstract

We combine existing perturbative results to show that a precise analytic determination of the charm-quark contribution to the hadronic light-by-light (HLbL) part of the muon anomalous magnetic moment is possible. Working in the $\overline{\mathrm{MS}}$ scheme, we include the NLO $\mathcal{O}(\alpha_s)$ correction, which significantly reduces the residual renormalization-scale dependence and the perturbative uncertainty. Our final result is $a_{\mu}^{\mathrm{HLbLc}}=3.65(25)\times 10^{-11}$, in good agreement with recent lattice determinations.

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Johan Bijnens, Nils Hermansson-Truedsson, Antonio Rodríguez-Sánchez. 2025-11-17. On the Charm Contribution to the Muon $g-2$ Light-by-Light. https://arxiv.org/abs/2511.13097

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