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arXiv · 2603.03120

An update on the HVP contribution to $g_μ{-}2$ in isoQCD from ETMC

Simone Bacchio·Alessandro De Santis·Antonio Evangelista·Roberto Frezzotti·Giuseppe Gagliardi·Marco Garofalo·Lorenzo Maio·Francesca Margari·Ferenc Pittler·Simone Romiti
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Abstract

We present an update on the determination of the leading-order hadronic vacuum polarisation contribution to the muon anomalous magnetic moment in isospin-symmetric QCD by the Extended Twisted Mass Collaboration. The calculation is based on five $N_f = 2+1+1$ gauge ensembles generated with Wilson-clover twisted-mass quarks at maximal-twist and near-physical pion masses, spanning four lattice spacings and two volumes. For the dominant quark-connected contributions, we employ two distinct valence-quark regularisations and present results for both the isovector and isoscalar components.

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Simone Bacchio, Alessandro De Santis, Antonio Evangelista, Roberto Frezzotti, Giuseppe Gagliardi, Marco Garofalo, Lorenzo Maio, Francesca Margari, Ferenc Pittler, Simone Romiti. 2026-03-03. An update on the HVP contribution to $g_μ{-}2$ in isoQCD from ETMC. https://arxiv.org/abs/2603.03120

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