Hadronic vacuum polarization contribution to the muon g?2 with (2+1)-flavor lattice QCD on a larger than (10??fm)4 lattice at the physical point

概要

We study systematic uncertainties in the lattice QCD computation of the hadronic vacuum polarization (HVP) contribution to the muon g?2. We investigate three systematic effects: the finite volume (FV) effect, the cutoff effect, and integration scheme dependence. We evaluate the FV effect at the physical pion mass on two different volumes of (5.4??fm)4 and (10.8??fm)4 using the PACS10 configurations at the same cutoff scale. For the cutoff effect, we compare two types of lattice vector operators, which are local and conserved (point-splitting) currents, by varying the cutoff scale on a larger than (10??fm)4 lattice at the physical point. For the integration scheme dependence, we compare the results between the coordinate- and momentum-space integration schemes at the physical point on a (10.8??fm)4 lattice. Our result for the HVP contribution to the muon g?2 is given by ahvpμ=737(9)(?+13?18)×10?10 in the continuum limit, where the first error is statistical and the second one is systematic.