Possible interpretations of the Pc (4312), Pc (4440), and Pc (4457)

Abstract

Based on our previous QCD sum rule studies on hidden-charm pentaquark states, we discuss possible interpretations of the Pc(4312), Pc(4440), and Pc(4457), which were recently observed by LHCb. Our results suggest that the Pc(4312) can be well interpreted as the [ςc++D̄-] bound state with JP=1/2-, while the Pc(4440) and Pc(4457) can be interpreted as the [ςc+D̄0] bound state with JP=1/2-, the [ςc∗++D̄-] and [ςc+D̄∗0] bound states with JP=3/2-, or the [ςc∗+D̄∗0] bound state with JP=5/2-. We propose to measure their spin-parity quantum numbers to verify these assignments.