Scalar mesons in radiative phi-meson decays into charged k-meson states

The role of $f_{0}(980)$ and $a_{0}(980)$ scalar meson intermediate states in the mechanism of radiative $\phi (1020)$ meson decay into two charged $K (494)$ mesons and a photon $\phi\rightarrow K^{+} + K^{-} + \gamma$ is investigated. For the contribution of scalar meson intermediate state two models are considered. In the kaon-loop model, the scalar meson intermediate state couples the final state to the initial $\phi$ meson through a charged kaon-loop. The second model, called no-structure model, consist of point-like coupling of intermediate scalar meson state to the initial state. It is found that in the kaon-loop model, scalar meson intermediate state results in a considerable modification of the pure Bremsstrahlung photon spectrum.