A lowest-order reaction matrix calculation of the binding energy in nuclear matter including the effect of the Δ(1236)

Abstract

The binding energy of nuclear matter in first-order Bethe-Brueckner theory is self-consistently calculated, using in 1S 0 a two-nucleon interaction with coupling to the Δ(1236) proposed by Green and Niskanen. The introduction of the Γ-resonance is found to give rise to a large repulsion of 4.7 MeV at k F = 1.4 fm −1. The contribution increases slightly faster than linearly with density. The Pauli-principle part, which also can be considered a lowest-order contribution from three-body forces, is extracted. Two separate evaluations of the attraction relating to the σ-meson in nuclear matter are performed.