Towards a measurement of the ωπ transition form factor

Two sets of experiments have been performed with the WASA detector at COSY. The intention is to compare the quality of the data between the pd! 3 He ! and pp!pp ! reactions, in the sense of a feasibility and background study for ! ! � 0 e + e decays. The aim of the physics program is to determine the transition form factor of the ! meson which does not agree with standard Vector Meson Dominance. As a first step towards the !� transition form factor, we study the decay with a real photon, ! ! � 0 . The status of the analysis is presented.