Scalar sigma meson effects in radiative rho^0-meson decays

We study the radiative ${\rho }^0\to {\pi }^{+}{\pi }^{-}\gamma$ and $\rho^0\to \pi^0\pi^0\gamma$ decays and we calculate their branching ratios 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. Our results for the branching ratios are in good agreement with the experimental values.