Speakers
Description
High-precision quantities such as the anomalous magnetic moment of the muon $a_\mu$ have gained increasing interest in the high-energy-physics community. In this context, the Muon g-2 experiment at Fermilab will have an unprecedented precision that requires a commensurate theoretical estimate. The corresponding error is fully driven by hadronic uncertainties, including uncertainties of the hadronic vacuum polarization and hadronic light-by-light contribution. In order to improve on the latter, a more extensive study of the resonance contributions (in the GeV range) is necessary. Specifically for the transition form factors of the the axial-vector- and tensor-meson resonances, the underlying mechanisms are not very well understood. We create a dynamical model for the transition form factors, making use of the Bardeen-Tung-Tarrach procedure in order to ensure gauge invariance, implement symmetry constraints, and control kinematic singularities. The form factors are then modelled by a sum of triangle Feynman diagrams with phenomenological input for the vertices.
