Dynamics of the πNN system: testing baryon-baryon interactions

We discuss hadronic properties of the πNN system above the pion production threshold energy. We calculate the effects of the nucleon-nucleon interaction in the presence of a spectator pion on observables of the several unitarity-coupled reactions. This interaction was left out in previous calculations which consequently violate unitarity. It induces a non-local nucleon-Δ interaction whose effects are compared with the effect of the instantaneous meson-exchange nucleon-Δ interaction. In a strictly meson exchange framework, we achieved an overall qualitative good description of the different reactions. Since some observables show sensitivity to the short range parametrizations of the model, we test in addition baryon-baryon potentials derived from a Constituent Quark Cluster Model including the nonperturbative π and σ exchanges. copyright 1995 American Institute of Physics