PHYSICAL REVIEW D, vol.67, no.7, 2003 (SCI-Expanded)
In an attempt to explain the latest experimental result about the branching ratio of omega-->pi(0)pi(0)gamma decay, we reexamine the mechanism of this decay in a phenomenological framework in which the contributions of vector meson dominance, chiral loops, sigma-meson intermediate state amplitudes, and the effects of omega-rho mixing are considered. We conclude that in order to obtain the experimental value of the branching ratio B(omega-->pi(0)pi(0)gamma) the sigma-meson amplitude, which makes a substantial contribution, should be included in the reaction mechanism and the effects of omega-rho mixing should be taken into account. We also estimate the coupling constant g(omegasigmagamma) as g(omegasigmagamma)=0.11, which is much smaller than the values suggested by light cone QCD sum rule calculations.