Strong LHCb evidence supporting the existence of the hidden-charm molecular pentaquarks

On 26 March 2019, at the Rencontres de Moriond QCD conference, the LHCb Collaboration reported the observation of three new pentaquarks, namely Pc(4312), Pc(4440), and Pc(4457), which are consistent with the loosely bound molecular hidden-charm pentaquark states composed of an S-wave charmed baryon Σc and an S-wave anticharmed meson (D̄, D̄*). In this work, we present a direct calculation by the one-boson-exchange model and demonstrate explicitly that the Pc(4312), Pc(4440), and Pc(4457) do correspond to the loosely bound ΣcD̄ with ($I=1/2$, JP=1/2^-), ΣcD̄* with ($I=1/2$, JP=1/2^-), and ΣcD̄* with ($I=1/2$, JP=3/2^-), respectively.