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 P-c(4312), P-c(4440), and P-c(4457), which are consistent with the loosely bound molecular hidden-charm pentaquark states composed of an S-wave charmed baryon Sigma(c) and an S-wave anticharmed meson ((D) over bar, (D) over bar*). In this work, we present a direct calculation by the one-boson-exchange model and demonstrate explicitly that the P-c(4312), P-c(4440), and P-c(4457) do correspond to the loosely bound Sigma(c)(D) over bar with (I = 1/2, J(P) = 1/2(-)), Sigma(c)(D) over bar* with (I = 1/2, J(P) = 1/2(-)), and Sigma(c)(D) over bar* with (I = 1/2, J(P) = 3/2(-)), respectively.