in the molecular picture

The three pentaquark states, , , and , discovered by the LHCb Collaboration in 2019, can be nicely arranged into a multiplet of of seven molecules dictated by heavy quark spin symmetry. In this work we employ the effective Lagrangian approach to investigate the two decay modes of , , and , via the triangle mechanism, assuming that and are and bound states but the spin of can be either or . Our results show that the spin of can not be discriminated through these two decay modes. The decay widths of and are estimated to be of order of 100 keV and 1 keV, respectively. The ratio of the partial decay widths of to is similar to the ratio of to , which could be used to check the molecular nature of and if they can be observed in the future.