Y(4626) as a molecular state from interaction {D}^*_s{bar{D}}_{s1}(2536)-{D}_s{bar{D}}_{s1}(2536)

Abstract

Recently, a new structure Y(4626) was reported by the Belle Collaboration in the process e^+e^-rightarrow D_s^+D_{s1}(2536)^-. In this work, we propose an assignment of the Y(4626) as a {D}^*_s{bar{D}}_{s1}(2536) molecular state, which decays into the D_s^+D_{s1}(2536)^- channel through a coupling between {D}^*_s{bar{D}}_{s1}(2536) and {D}_s{bar{D}}_{s1}(2536) channels. With the help of the heavy quark symmetry, the potential of the interaction {D}^*_s{bar{D}}_{s1}(2536)-{D}_s{bar{D}}_{s1}(2536) is constructed within the one-boson-exchange model, and inserted into the quasipotential Bethe–Salpeter equation. The pole of obtained scattering amplitude is searched for in the complex-energy plane, which corresponds to a molecular state from the interaction {D}^*_s{bar{D}}_{s1}(2536)-{D}_s{bar{D}}_{s1}(2536). The results suggest that a pole is produced near the {D}^*_s{bar{D}}_{s1}(2536) threshold, which exhibits as a peak in the invariant mass spectrum of the {D}_s{bar{D}}_{s1}(2536) channel at about 4626 MeV. It obviously favors the Y(4626) as a {D}^*_s{bar{D}}_{s1}(2536) molecular state. In the same model, other molecular states from the interaction {D}^*_s{bar{D}}_{s1}(2536)-{D}_s{bar{D}}_{s1}(2536) are also predicted, which can be checked in future experiments.