We work in a chiral invariant quark model, with a condensed vacuum, characterized by only one parameter. Bound state equations for the nucleon and Δ are solved in order to obtain an updated value of their radii and masses. Nucleon-nucleon $S$-wave scattering is studied in the resonating group method framework both for isospin $T=1\mathrm{}$ and $T=0.\mathrm{}$ The phase shifts are calculated and an equivalent local potential, which is consistent with $K-N$ scattering, is derived. The result is a reasonable microscopic short range repulsion in the nucleon-nucleon interaction.

• Received 3 February 1997

DOI:https://doi.org/10.1103/PhysRevC.56.670