Pion mass dependence of the HVP contribution to muon $g-2$

摘要

One of the systematic errors in some of the current lattice computations ofthe HVP contribution to the muon anomalous magnetic moment $g-2$ is thatassociated with the extrapolation to the physical pion mass. We investigatethis extrapolation assuming lattice pion masses in the range of 220 to 440 MeVwith the help of two-loop chiral perturbation theory, and find that such anextrapolation is unlikely to lead to control of this systematic error at the 1%level. This remains true even if various proposed tricks to improve the chiralextrapolation are taken into account.