Dibaryon resonances and short-range $NN$ interaction

Abstract

The dibaryon concept for the nuclear force is presented, 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 $NN$ interaction model, a microscopic six-quark description of the $NN$ system is used, in which symmetry aspects play a special role. It is shown that the $NN$ interaction in all important partial waves can be described properly by a superposition of the long-range $t$-channel one-pion exchange and the $s$-channel exchange by an intermediate dibaryon. The developed model gives a good description of both elastic phase shifts and inelasticities of $NN$ scattering in all $S$, $P$, $D$ and $F$ partial waves at energies from zero to 600 - 800 MeV and even higher.The parameters of the intermediate six-quark states corresponding to the best fit of $NN$ scattering data are found to be consistent with the parameters of the known dibaryon resonances in those $NN$ partial configurations where their existence has been experimentally confirmed. Predictions for new dibaryon states are given as well.