Rich structure of the hidden-charm pentaquarks near threshold regions

The recent discoveries and observations of pentaquarks and tetraquarks by high-energy accelerator facilities have accumulated evidence of the existence of multiquark hadrons with heavy quarks, as discussed from the early stage of the prediction of quarks. We construct a coupled-channel model for the hidden-charm pentaquarks with strangeness whose quark content is udscc over bar , Pcs, described as Ac E(0*) c over bar D(*) molecules, produced by the cooperation of the heavy quark and chiral symmetries, coupled to a five-quark core. We reproduce the experimental mass of Pcs, of which LHCb has announced the discovery. Furthermore, our result supports the quantum numbers that are preferred by the experiment. Our predictions indicate the existence of additional Pcs's in proximity to molecular threshold regions, which can be further investigated by LHCb. over bar D(*) s ,