Book Description

The role of scalar mesons in radiative vector meson decays is investigated. The effects of scalar-isoscalar f_{0}(980) and scalar-isovector a_{0}(980) mesons are studied in the mechanism of the radiative Phi->pi{+}pi{-}gamma and phi->pi{0}eta gamma decays, respectively. A phenomenological approach is used to study the radiative phi->pi{+}p{-}gamma decay by considering the contributions of sigma-meson, rho-meson and f_{0}-meson. The interference effects between different contributions are analyzed and the branching ratio for this decay is calculated. The radiative phi->pi{0}eta gamma decay is studied within the framework of a phenomenological approach in which the contributions of rho-meson, chiral loop and a_{0}-meson are considered. The interference effects between different contributions are examined and the coupling constants g_{phi a_{0} gamma} and g_{a_{0}K{+}K{-}} are estimated using the experimental branching ratio for the phi->pi{0}eta gamma decay. Furthermore, the radiative rho{0}pi{+}pi{-}gamma$ and rho{0}->pi{0}pi{0}gamma decays are studied to investigate the role of scalar-isoscalar sigma-meson. The branching ratios of the rho{0}->pi{+}pi{-}gamma and rho{0}->pi{0}pi{0}gamma decays are calculated using a phenomenological approach by adding to the amplitude calculated within the framework of chiral perturbation theory and vector meson dominance the amplitude of sigma-meson intermediate state. In all the decays studied the scalar meson intermediate states make important contributions to the overall amplitude.