Production of a0 mesons in pp and pn reactions

We investigate the cross section for the reaction NN → NNa0 near the threshold and at medium energies. An effective Lagrangian approach with a one-pion exchange is applied to analyse different contributions to the cross section for different isospin channels. The Reggeon exchange mechanism is also considered. The results are used to calculate the contribution of the a0 meson to the cross sections and invariant K mass distributions of the reactions pp → pnK+0 and pp → ppK+K−. We found that the experimental observation of a+0 mesons in the reaction pp → pnK+ 0 is much more promising than the observation of a00 mesons in the reaction pp → pp K+K−.