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arXiv · 1711.04980

Hadronic vacuum polarization contribution to the anomalous magnetic moments of leptons from first principles

Wuppertal collaboration·Sz. Borsanyi·Z. Fodor·C. Hoelbling·T. Kawanai·S. Krieg·L. Lellouch·R. Malak·K. Miura·K. K. Szabo·C. Torrero·B. C. Toth
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Abstract

We compute the leading, strong-interaction contribution to the anomalous magnetic moment of the electron, muon and tau using lattice quantum chromodynamics (QCD) simulations. Calculations include the effects of $u$, $d$, $s$ and $c$ quarks and are performed directly at the physical values of the quark masses and in volumes of linear extent larger than $6\,\mathrm{fm}$. All connected and disconnected Wick contractions are calculated. Continuum limits are carried out using six lattice spacings. We obtain $a_e^\mathrm{LO-HVP}=189.3(2.6)(5.6)\times 10^{-14}$, $a_\mu^\mathrm{LO-HVP}=711.1(7.5)(17.4)\times 10^{-10}$ and $a_\tau^\mathrm{LO-HVP}=341.0(0.8)(3.2)\times 10^{-8}$, where the first error is statistical and the second is systematic.

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Wuppertal collaboration, Sz. Borsanyi, Z. Fodor, C. Hoelbling, T. Kawanai, S. Krieg, L. Lellouch, R. Malak, K. Miura, K. K. Szabo, C. Torrero, B. C. Toth. 2017-11-14. Hadronic vacuum polarization contribution to the anomalous magnetic moments of leptons from first principles. https://doi.org/10.1103/physrevlett.121.022002

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