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arXiv · 2501.19350

Valence leading isospin breaking contributions to $a_{\mu}^{\mathrm{HVP-LO}}$

Simone Bacchio·Antonio Evangelista·Roberto Frezzotti·Giuseppe Gagliardi·Marco Garofalo·Nikolaos Kalntis·Simone Romiti·Francesco Sanfilippo·Nazario Tantalo
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Abstract

By employing the RM123 approach to QCD+QED, we computed the valence quark-connected isospin-breaking corrections to the light, strange and charm contributions at leading order in $\alpha_{\mathrm{em}}$ and $\left(\mu_d-\mu_u\right) / \Lambda_{\mathrm{QCD}}$. Here we report the preliminary results on two different volumes ($L \sim 3.8$ fm and $L \sim 5.1$ fm) and a fixed lattice spacing (corresponding to $a_{\text {isoQCD }} \sim 0.07951(4)$ fm), obtained in the framework of the ongoing computation by ETMC of the leading-order hadronic vacuum polarization (HVP) contribution to the muon anomalous magnetic moment $a_\mu^{\mathrm{HVP}}$ in QCD+QED.

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Simone Bacchio, Antonio Evangelista, Roberto Frezzotti, Giuseppe Gagliardi, Marco Garofalo, Nikolaos Kalntis, Simone Romiti, Francesco Sanfilippo, Nazario Tantalo. 2025-01-31. Valence leading isospin breaking contributions to $a_{\mu}^{\mathrm{HVP-LO}}$. https://arxiv.org/abs/2501.19350

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