Effects of a quark-model-based nucleon-Δ potential on the two-nucleon system above pion threshold

The interaction between a nucleon and a Δ isobar is studied. The nucleon-Δ potential is derived from a nonrelativistic quark model. It is compared with a corresponding one based on meson exchange. The quark-model potential is strongly repulsive at small relative distances. The effects of the potential on elastic and inelastic nucleon-nucleon and pion-deuteron scattering are calculated. Some observables show sensitivity with respect to the chosen nucleon-Δ potential