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arXiv · 2301.08274

Light-quark connected intermediate-window contributions to the muon $g-2$ hadronic vacuum polarization from lattice QCD

Alexei Bazavov·Christine Davies·Carleton DeTar·Aida X. El-Khadra·Elvira Gámiz·Steven Gottlieb·William I. Jay·Hwancheol Jeong·Andreas S. Kronfeld·Shaun Lahert·G. Peter Lepage·Michael Lynch·Andrew T. Lytle·Paul B. Mackenzie·Craig McNeile·Ethan T. Neil·Curtis T. Peterson·Gaurav Ray·James N. Simone·Ruth S. Van de Water·Alejandro Vaquero
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Abstract

We present a lattice-QCD calculation of the light-quark connected contribution to window observables associated with the leading-order hadronic vacuum polarization contribution to the anomalous magnetic moment of the muon, $a_\mu^{\mathrm{HVP,LO}}$. We employ the MILC Collaboration's isospin-symmetric QCD gauge-field ensembles, which contain four flavors of dynamical highly-improved-staggered quarks with four lattice spacings between $a\approx 0.06$-$0.15$~fm and close-to-physical quark masses. We consider several effective-field-theory-based schemes for finite-volume and other lattice corrections and combine the results via Bayesian model averaging to obtain robust estimates of the associated systematic uncertainties. After unblinding, our final results for the intermediate and ``W2'' windows are $a^{ll,{\mathrm W}}_{\mu}(\mathrm{conn.})=206.6(1.0) \times 10^{-10}$ and $a^{ll,\mathrm {W2}}_{\mu}(\mathrm{conn.}) = 100.7(3.2)\times 10^{-10}$, respectively.

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Alexei Bazavov, Christine Davies, Carleton DeTar, Aida X. El-Khadra, Elvira Gámiz, Steven Gottlieb, William I. Jay, Hwancheol Jeong, Andreas S. Kronfeld, Shaun Lahert, G. Peter Lepage, Michael Lynch, Andrew T. Lytle, Paul B. Mackenzie, Craig McNeile, Ethan T. Neil, Curtis T. Peterson, Gaurav Ray, James N. Simone, Ruth S. Van de Water, Alejandro Vaquero. 2023-01-19. Light-quark connected intermediate-window contributions to the muon $g-2$ hadronic vacuum polarization from lattice QCD. https://doi.org/10.1103/physrevd.107.114514

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