Chiral loops and VMD in the V->PPgamma decays

Abstract

We evaluate radiative decays of $ρ$ and $ω$ going to two neutral mesons, $π^{0} π^{0}$ and $π^{0} η$. We use the sequential vector decay mechanisms in addition to chiral loops and $ρ$-$ω$ mixing. The chiral loops are obtained using elements of $UχPT$ successfully applied in the study of meson-meson interactions up to 1.2 GeV. The chiral loops are found very important in the case of the $ρ\to π^{0} π^{0} γ$ decay and small in the other cases. A good agreement with present measurements of $ρ\to π^{0} π^{0} γ$ and $ω\to π^{0} π^{0}γ$ is obtained and predictions are made for the other decays where the rates obtained are rather small.

16 pages, 4 figures. To be published in Nucl. Phys. A