Speaker
Description
Electromagnetic transition form factors of light mesons are important inputs to the calculations of the hadronic light-by-light scattering contribution to the Standard Model prediction of the anomalous magnetic moment of the muon. However, data in the relevant regions of momentum transfer are scarce. The BESIII experiment at the $e^+ e^-$ collider BEPCII has collected the world's largest data sets in the $\tau$-charm energy region, including, but not limited to more than $20\,{\rm fb}^{-1}$ of data at a center-of-mass energy of 3.773 GeV/$c^2$. The data are analyzed for two-photon collisions in events of the type $e^+e^- \to e^+ e^- P$, with $P = \pi^0, \eta^{(\prime)}, f_1(1285), \pi^0\pi^0$, and $\pi^+\pi^-$. The aim is to study the momentum dependence of the respective space-like electromagnetic transition form factors. In this presentation we discuss recent results and prospects of ongoing analyses.
