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arXiv · 2308.04217

Puzzles in the hadronic contributions to the muon anomalous magnetic moment

Gilberto Colangelo·Martin Hoferichter·Peter Stoffer
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Abstract

We summarize recent developments in the Standard-Model evaluation of the anomalous magnetic moment of the muon $a_\mu$, both in the hadronic-light-by-light and hadronic-vacuum-polarization contributions. The current situation for the latter is puzzling as we are confronted with multiple discrepancies that are not yet understood. We present updated fits of a dispersive representation of the pion vector form factor to the new CMD-3 data set and quantify the tensions with the other high-statistics $e^+e^-\to\pi^+\pi^-$ experiments in the contribution to $a_\mu$ in the energy range up to 1 GeV, as well as in the corresponding contribution to the intermediate Euclidean window.

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Gilberto Colangelo, Martin Hoferichter, Peter Stoffer. 2023-08-08. Puzzles in the hadronic contributions to the muon anomalous magnetic moment. https://arxiv.org/abs/2308.04217

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