On the possibility to measure the π0 → γγ decay width and the γ*γ → π0 transition form factor with the KLOE-2 experiment

A possibility of KLOE-2 experiment to measure the width Gamma(pi 0 -> gamma gamma) and the pi(0) gamma gamma* form factor F(Q(2)) at low invariant masses of the virtual photon in the space-like region is considered. This measurement is an important test of the strong interaction dynamics at low energies. The feasibility is estimated on the basis of a Monte-Carlo simulation. The expected accuracy for Gamma(pi 0 -> gamma gamma) is at a per cent level, which is better than the current experimental world average and theory. The form factor will be measured for the first time at Q(2) <= 0.1 GeV2 in the space-like region. The impact of these measurements on the accuracy of the pion-exchange contribution to the hadronic light-by-light scattering part of the anomalous magnetic moment of the muon is also discussed.