Finite width effects in φ radiative decays

The decay widths φ → γf0(980) and φ → γa0(980) are calculated taking into account the finite widths of the scalar resonances f0(980) and a0(980). The latter are shown to be essential in order to obtain meaningful results. Simultaneously we also study the decays φ → γππ and γπη where a good reproduction of the recent experimental data is obtained, pointing out the necessity of a φγKK̄ contact vertex. The calculated decay rates to γf0(980) and γa0(980) are in good agreement with the experimental ones without invoking isospin breaking in the couplings of the f0(980) and a0(980) resonances to the KK and KK̄ channels, at odds with recent proposals. The derived formula for calculating these φ radiative decay widths can be also applied in their own experimental analyses in order to obtain more precise results.