2024/11/29 by Martin Hoferichter, Peter Stoffer, Maximilian Zillinger · 1 voice · 1 citation
Physics and Astronomy · #hep-ph #hep-ex #hep-lat #nucl-th
paper · pdf · doi:10.1007/jhep02(2025)121
arxiv published 2024/11/29 · arxiv updated 2025/02/20
In this work, we present an evaluation of subleading effects in the hadronic light-by-light contribution to the anomalous magnetic moment of the muon. Using a recently derived optimized basis, we first study the matching of axial-vector contributions to short-distance constraints at the level of the scalar basis functions, finding that also the tails of the pseudoscalar poles and tensor mesons play a role. We then develop a matching strategy that allows for a combined evaluation of axial-vector and short-distance constraints, supplemented by an estimate of tensor-meson contributions based on simplified assumptions for their transition form factors. Uncertainties are primarily propagated from the axial-vector transition form factors and the variation of the matching scale, but we also consider estimates of the low-energy effect of hadronic states not explicitly included. In total, we obtain aμHLbL|subleading=33.2(7.2)× 10-11, which in combination with previously evaluated contributions in the dispersive approach leads to aμHLbL|total=101.9(7.9)× 10-11.