Y(4260) as a four-quark state

Abstract

We treat the $Y(4260)$ resonance as a four-quark state in the framework of the covariant confining quark model. We study two choices of the interpolating current, either the molecular-type current which effectively corresponds to the product of $D$ and ${\overline{D}}_{1}$ quark currents or tetraquark one. In both cases, we calculate the widths of decays $Y(4260)\ensuremath{\rightarrow}{Z}_{c}(3900)+\ensuremath{\pi}$ and $Y(4260)\ensuremath{\rightarrow}{D}^{(*)}+{\overline{D}}^{(*)}$. It is found that in both approaches the mode $Y\ensuremath{\rightarrow}{Z}_{c}^{+}+{\ensuremath{\pi}}^{\ensuremath{-}}$ is enhanced compared with the open-charm modes. However, the absolute value of the $Y\ensuremath{\rightarrow}{Z}_{c}^{+}+{\ensuremath{\pi}}^{\ensuremath{-}}$ decay width obtained in molecular picture is arguably too large. On the other hand, the value obtained in tetraquark picture is reasonable.