Monday, October 26, 9:00 a.m.
Bastian Kubis - Bonn University
Hadronic contributions to the muon's anomalous magnetic moment from analyticity
Abstract:
The uncertainty in the Standard Model prediction for the anomalous magnetic moment of the muon is by far dominated by hadronic effects. I discuss how different important contributions can be made more precise by using rigorous theoretical constraints, especially due to analyticity: this includes hadronic vacuum polarisation due to $3\pi$ and $\pi^0\gamma$ intermediate states, and hadronic light-by-light scattering via the largest individual contribution therein, the $\pi^0$-pole term. The latter is determined in terms of the $\pi^0$ transition form factor, for which a representation that incorporates all low-lying singularities and matches correctly onto the asymptotic behaviour expected from perturbative QCD has been derived. Further, ongoing, extensions of this work will briefly be mentioned.