Numerical investigation of finite-volume effects for the HVP

Abstract

Abstract. It is important to correct for finite-volume (FV) effects in the presence of QED, since these effects are typically large due to the long range of the electromagnetic interaction. We recently made the first lattice calculation of electromagnetic corrections to the hadronic vacuum polarisation (HVP). For the HVP, an analytical derivation of FV corrections involves a two-loop calculation which has not yet been carried out. We instead calculate the universal FV corrections numerically, using lattice scalar QED as an effective theory. We show that this method gives agreement with known analytical results for scalar mass FV effects, before applying it to calculate FV corrections for the HVP. This method for numerical calculation of FV effects is also widely applicable to quantities beyond the HVP.

The anomalous magnetic moment of the muon: status of lattice QCD calculations

“…Here, the results are obtained to all orders in (or within the electro-quenched approximation). For the HVP, this method has been studied by the RBC collaboration [ 84 ] and the QCDSF collaboration [ 85 ].…”