Lattice calculations of the leading hadronic contribution to (g-2)_mu

TL;DR

This paper discusses a lattice QCD approach to calculating the dominant hadronic contribution to the muon's anomalous magnetic moment, employing improved techniques to enhance accuracy and computational efficiency.

Contribution

The study introduces a new combination of currents and boundary conditions to improve the precision and efficiency of lattice calculations of a_mu^HLO.

Findings

Reduced numerical effort through current combination

Enhanced momentum resolution with twisted boundary conditions

Extended ensembles to lower pion masses for better chiral behavior analysis

Abstract

We report on our ongoing project to calculate the leading hadronic contribution to the anomalous magnetic moment of the muon a_mu^HLO using two dynamical flavours of non-perturbatively O(a) improved Wilson fermions. In this study, we changed the vacuum polarisation tensor to a combination of local and point-split currents which significantly reduces the numerical effort. Partially twisted boundary conditions allow us to improve the momentum resolution of the vacuum polarisation tensor and therefore the determination of the leading hadronic contribution to (g-2)_mu. We also extended the range of ensembles to include a pion mass below 200 MeV which allows us to check the non-trivial chiral behaviour of a_mu^HLO.