D bar Σc* and Dbar*Σc interactions and the LHCb hidden-charmed pentaquarks

Very recently, two hidden-charmed resonances P_c (4380) and P_c (4450) consistent with pentaquark states were observed at the LHCb detector. The two P_c states locate just below the D bar Σ_c^* and D^bar*Σ_c thresholds with mass of gaps about 5 and 15 MeV, respectively. Inspired by this fact we perform a dynamical investigation about the D bar Σ_c^* (2520) and D^bar*Σ_c (2455) interactions which are described by the meson exchanges. A bound state which carries spin-parity J^P = 3 /2^- is produced from the D bar Σ_c^* (2520) interaction, which is consistent with the P_c (4380) observed at the LHCb detector. From the D^*Σ_c (2455) interaction, a bound state with 5 /2⁺ is produced, which can be related to the P_c (4450). The results suggest that the P_c (4380) and P_c (4450) are good candidates of D bar Σ_c^* (2520) and D^bar*Σ_c (2455) molecular states, respectively.