Quark model estimate of hidden-charm pentaquark resonances

A quark model, which reproduces the ground-state mesons and baryons, i.e., the threshold energies, is applied to the \(qqqc\bar c\) configurations, where \(q\) is a light quark and~\(c\) the charmed quark. In the calculation, several open channels are explicitly included such as \(\Jpsi +N\), \(\eta_c+N\), \(\Lambda_c +D\), etc. To distinguish genuine resonances and estimate their width, we employ Gaussian Expansion Method supplemented by the real scaling method (stabilization). No resonance is found at the energies of the \(P_c(4380)\) and \(P_c(4450)\) pentaquarks. On the other hand, there is a sharp resonant state at 4690\,MeV with \(J=1/2^-\) state and another one at 4920\,MeV with \(J=3/2^-\) state, which have a compact structure.