Model dependence of unitary isobar model treatments of NNNNπat intermediate energies

Abstract
We compare two ‘‘conventional’’ relativistic unitary isobar models for the NN→NNπ reaction. One model, which preserves two- and three-body unitarity, contains only pion exchange, while the other, based on a two-body coupled-channels approach, includes heavier meson exchanges. Thus, we attempt to identify the model dependence of predictions for the NN→NNπ process over a large part of final state phase space. Differential cross sections and a variety of spin observables are examined. Implications for the identification of exotic dibaryon resonances are briefly discussed.