English

Hadronic vacuum polarization for the muon $g-2$ from lattice QCD: Complete short and intermediate windows

High Energy Physics - Lattice 2025-05-16 v3 High Energy Physics - Experiment High Energy Physics - Phenomenology

Abstract

We present complete results for the hadronic vacuum polarization (HVP) contribution to the muon anomalous magnetic moment aμa_\mu in the short- and intermediate-distance window regions, which account for roughly 10% and 35% of the total HVP contribution to aμa_\mu, respectively. In particular, we perform lattice-QCD calculations for the isospin-symmetric connected and disconnected contributions, as well as corrections due to strong isospin-breaking. For the short-distance window observables, we investigate the so-called log-enhancement effects as well as the significant oscillations associated with staggered quarks in this region. For the dominant, isospin-symmetric light-quark connected contribution, we obtain aμll,SD(conn.)=48.139(11)stat(91)syst[92]total×1010a^{ll,\,{\mathrm{SD}}}_{\mu}(\mathrm{conn.}) = 48.139(11)_{\mathrm{stat}}(91)_{\mathrm{syst}}[92]_{\mathrm{total}} \times 10^{-10} and aμll,W(conn.)=206.90(14)stat(61)syst[63]total×1010a^{ll,\,{\mathrm{W}}}_{\mu}(\mathrm{conn.}) = 206.90(14)_{\mathrm{stat}}(61)_{\mathrm{syst}}[63]_{\mathrm{total}} \times 10^{-10}. We use Bayesian model averaging to fully estimate the covariance matrix between the individual contributions. Our determinations of the complete window contributions are aμSD=69.05(1)stat(21)syst[21]total×1010a^{{\mathrm{SD}}}_{\mu} = 69.05(1)_{\mathrm{stat}}(21)_{\mathrm{syst}}[21]_{\mathrm{total}} \times 10^{-10} and aμW=236.45(17)stat(83)syst[85]total×1010a^{{\mathrm{W}}}_{\mu} = 236.45(17)_{\mathrm{stat}}(83)_{\mathrm{syst}}[85]_{\mathrm{total}} \times 10^{-10}. This work is part of our ongoing effort to compute all contributions to HVP with an overall uncertainty at the few permille level.

Keywords

Cite

@article{arxiv.2411.09656,
  title  = {Hadronic vacuum polarization for the muon $g-2$ from lattice QCD: Complete short and intermediate windows},
  author = {Alexei Bazavov and David A. Clarke and Christine Davies and Carleton DeTar and Aida X. El-Khadra and Elvira Gámiz and Steven Gottlieb and Anthony V. Grebe and Leon Hostetler and William I. Jay and Hwancheol Jeong and Andreas S. Kronfeld and Shaun Lahert and Jack Laiho and G. Peter Lepage and Michael Lynch and Andrew T. Lytle and Craig McNeile and Ethan T. Neil and Curtis T. Peterson and James N. Simone and Jacob W. Sitison and Ruth S. Van de Water and Alejandro Vaquero},
  journal= {arXiv preprint arXiv:2411.09656},
  year   = {2025}
}

Comments

v3: Updated to reflect published version, which includes minor updates to the prose in Section IV and a correction to the statistical error estimate of a^W_{\mu}. Final results unchanged