Scalar σ meson effects in ρ and ω decays into π0π0γ

The complementarity between chiral perturbation theory and the linear sigma model in the scalar channel is exploited to study π0π0 production in ρ and ω radiative decays, where the effects of a low mass scalar resonance σ(500) should manifest. The recently reported data on ρ→π0π0γ seem to require the contribution of a low mass and moderately narrow σ(500). The properties of this controversial state could be fixed by improving the accuracy of these measurements. Data on ω→π0π0γ can also be accommodated in our framework, but are much less sensitive to the σ(500) properties.