We introduce a new method for calculating the O(α3) 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 Π^(q2), 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 Π^(q2) that were obtained on four-flavor QCD gauge-field configurations with physical light-quark masses. We obtain 1010aμHVP,HO=−9.3(1.3), in agreement with, but with a larger uncertainty than, determinations from e+e−→hadrons data plus dispersion relations.
@article{arxiv.1806.08190,
title = {Higher-order hadronic-vacuum-polarization contribution to the muon g-2 from lattice QCD},
author = {Bipasha Chakraborty and Christine T. H. Davies and Jonna Koponen and G. Peter Lepage and Ruth S. Van de Water},
journal= {arXiv preprint arXiv:1806.08190},
year = {2018}
}
Comments
Expanded and clarified discussion and revised Figure 4. Results unchanged. 11 pages, 5 tables, 5 figures. Version accepted to Physical Review D