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arXiv · 1806.08190

Higher-order hadronic-vacuum-polarization contribution to the muon g-2 from lattice QCD

Bipasha Chakraborty·Christine T. H. Davies·Jonna Koponen·G. Peter Lepage·Ruth S. Van de Water
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Abstract

We introduce a new method for calculating the ${\rm O}(α^3)$ hadronic-vacuum-polarization contribution to the muon anomalous magnetic moment from ${ab-initio}$ lattice QCD. We first derive expressions suitable for computing the higher-order contributions either from the renormalized vacuum polarization function $\hatΠ(q^2)$, or directly from the lattice vector-current correlator in Euclidean space. We then demonstrate the approach using previously-published results for the Taylor coefficients of $\hatΠ(q^2)$ that were obtained on four-flavor QCD gauge-field configurations with physical light-quark masses. We obtain $10^{10} a_μ^{\rm HVP,HO} = -9.3(1.3)$, in agreement with, but with a larger uncertainty than, determinations from $e^+e^- \to {\rm hadrons}$ data plus dispersion relations.

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Bipasha Chakraborty, Christine T. H. Davies, Jonna Koponen, G. Peter Lepage, Ruth S. Van de Water. 2018-11-02. Higher-order hadronic-vacuum-polarization contribution to the muon g-2 from lattice QCD. https://doi.org/10.1103/physrevd.98.094503

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