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arXiv · 2411.11719

Hadronic light-by-light scattering contribution to the anomalous magnetic moment of the muon at the physical pion mass

Zoltan Fodor·Antoine Gerardin·Laurent Lellouch·Kalman K. Szabo·Balint C. Toth·Christian Zimmermann
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Abstract

We present a lattice QCD calculation of the hadronic light-by-light scattering contribution to the anomalous magnetic moment of the muon using $N_f=2+1+1$ flavors of staggered quarks with masses tuned to their physical values. Our final result, in the continuum limit, reads $a_{\mu}^{\mathrm{hlbl}} = 125.5(11.6)_{\mathrm{stat}}(0.4)_{\mathrm{syst}} \times 10^{-11}$ where the first error is statistical and the second is systematic. Light, strange and charm-quark contributions are considered. In addition to the connected and leading disconnected contributions, we also include an estimate of the sub-leading disconnected diagrams. Our result is compatible with previous lattice QCD and data-driven dispersive determinations.

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Zoltan Fodor, Antoine Gerardin, Laurent Lellouch, Kalman K. Szabo, Balint C. Toth, Christian Zimmermann. 2024-11-18. Hadronic light-by-light scattering contribution to the anomalous magnetic moment of the muon at the physical pion mass. https://arxiv.org/abs/2411.11719

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