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arXiv · 1601.03071

The hadronic vacuum polarization contribution to $a_{\mu}$ from full lattice QCD

Bipasha Chakraborty·C. T. H. Davies·P. G. de Oliviera·J. Koponen·G. P. Lepage·R. van de Water
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Abstract

We determine the contribution to the anomalous magnetic moment of the muon from the $\alpha^2_{\mathrm{QED}}$ hadronic vacuum polarization diagram using full lattice QCD and including $u/d$ quarks with physical masses for the first time. We use gluon field configurations that include $u$, $d$, $s$ and $c$ quarks in the sea at multiple values of the lattice spacing, multiple $u/d$ masses and multiple volumes that allow us to include an analysis of finite-volume effects. We obtain a result for $a_{\mu}^{\mathrm{HVP,LO}}$ of $667(6)(12)$, where the first error is from the lattice calculation and the second includes systematic errors from missing QED and isospin-breaking effects and from quark-line disconnected diagrams. Our result implies a discrepancy between the experimental determination of $a_{\mu}$ and the Standard Model of 3$\sigma$.

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Bipasha Chakraborty, C. T. H. Davies, P. G. de Oliviera, J. Koponen, G. P. Lepage, R. van de Water. 2016-01-12. The hadronic vacuum polarization contribution to $a_{\mu}$ from full lattice QCD. https://doi.org/10.1103/physrevd.96.034516

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