6533b820fe1ef96bd12791f2

RESEARCH PRODUCT

Position-space approach to hadronic light-by-light scattering in the muon $g-2$ on the lattice

Jeremy GreenAndreas NyffelerNils AsmussenHarvey B. Meyer

subject

PhysicsParticle physicsMuonAnomalous magnetic dipole momentScatteringHigh Energy Physics - Lattice (hep-lat)FOS: Physical sciencesPosition and momentum spaceLattice QCDLight scatteringHigh Energy Physics - PhenomenologyHigh Energy Physics - LatticeHigh Energy Physics - Phenomenology (hep-ph)Lattice (order)Vacuum polarization

description

The anomalous magnetic moment of the muon currently exhibits a discrepancy of about three standard deviations between the experimental value and recent Standard Model predictions. The theoretical uncertainty is dominated by the hadronic vacuum polarization and the hadronic light-by-light (HLbL) scattering contributions, where the latter has so far only been fully evaluated using different models. To pave the way for a lattice calculation of HLbL, we present an expression for the HLbL contribution to $g-2$ that involves a multidimensional integral over a position-space QED kernel function in the continuum and a lattice QCD four-point correlator. We describe our semi-analytic calculation of the kernel and test the approach by evaluating the $\pi^0$-pole contribution in the continuum.

https://dx.doi.org/10.48550/arxiv.1609.08454