Nϕstates in a chiral quark model

Abstract

The structures of $N\ensuremath{\phi}$ states with spin-parity ${J}^{p}=3/{2}^{\ensuremath{-}}$ and ${J}^{p}=1/{2}^{\ensuremath{-}}$ are dynamically studied in both the chiral SU(3) quark model and the extended chiral SU(3) quark model by solving a resonating group method (RGM) equation. The model parameters are taken from our previous work, which gave a satisfactory description of the energies of the baryon ground states, the binding energy of the deuteron, the nucleon-nucleon (NN) scattering phase shifts, and the hyperon-nucleon (YN) cross sections. The channel coupling of $N\ensuremath{\phi}$ and $\ensuremath{\Lambda}{K}^{*}$ is considered, and the effect of the tensor force which results in the mixing of S and D waves is also investigated. The results show that the $N\ensuremath{\phi}$ state has an attractive interaction, and in the extended chiral SU(3) quark model such an attraction plus the channel coupling effect can consequently make for an $N\ensuremath{\phi}$ quasi-bound state with several MeV binding energy.