Scalar σ meson effects in ρ and ω decays into π0π0γ
Abstract The complementarity between chiral perturbation theory and the linear sigma model in the scalar channel is exploited to study π 0 π 0 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 → π 0 π 0 γ 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 → π 0 π 0 γ can also be accommodated in our framework, but are much less sensitive to the σ (500) properties.