Contribution of the direct decay φ→π+π−γ to the process e+e−→π+π−γ at DAΦNE

The potential of DAΦNE to explore direct radiative decay φ→π+π−γ is studied in detail. Predictions of different theoretical models for this decay are compared. We find that it should be possible to discriminate between these models at DAΦNE in one year, even assuming a relatively low luminosity L=1031 cm−2 s−1. The influence of the decay φ→π+π−γ on the measurement of total cross section σ(e+e−→hadrons) by tagging a photon in the reaction e+e−→π+π−γ is also discussed.