Dibaryon resonances and short-range $NN$ interaction

Abstract

The dibaryon concept for the nuclear force is considered, assuming that the main attraction between the nucleons at medium distances is determined by the s-channel exchange of an intermediate six-quark (dibaryon) state. To construct the respective N N interaction model, a microscopic sixquark description of the N N system is used, in which symmetry aspects play a special role. The interaction within the dibaryon model includes a superposition of t-channel long-range one-pion exchange and s-channel dibaryon exchange. This interaction model is shown to give a good description of both elastic phase shifts and inelasticities of N N scattering in various partial waves in a broad energy range from zero to 600-800 MeV and even higher. It is shown also that the suggested coupling between the external N N channel and internal 6q channel leads to a dressing of the intermediate dibaryon state. Finally, the parameters of the dressed dibaryons corresponding to the best fit of N N scattering data turn out to be very close to the parameters of the observed dibaryon resonances in those N N partial configurations where their existence has been experimentally confirmed.