Scalar Mesons Effects in Radiative Decays of Vector Mesons

We review the results of our calculations for the energy spectrum and branching ratios of V0 → P0P0'γ in the context of a U (3) x U (3) linear sigma model which includes 't Hooft interaction. The corresponding amplitudes reduce to the O(p4) predictions of CHPT for these processes in the limit of heavy scalars (or equivalently in the low energy region). In this sense our approach extend to the resonance region the O(p4) predictions of CHPT in a chiral invariant way. The measured energy spectrum and branching ratios are well described in this formalism. In particular, the negative interference shown by the data around mππ = 500 MeV in φ → π0π0γ arises in a natural way in this framework