On the charm contribution to the muon g - 2 light-by-light

We combine existing perturbative results to show that a precise analytic determination of the charm-quark contribution to the hadronic light-by-light (HLbL) part of the muon anomalous magnetic moment is possible. Working in the MS ‾ scheme, we include the NLO O ( α s ) correction, which significantly reduces the residual renormalization-scale dependence and the perturbative uncertainty. Our final result is a μ HLbLc = 3.65 ( 25 ) × 10 − 11 , in good agreement with recent lattice determinations.