Possible Molecular States of $D_s^{\ast }{\bar{D}}_s^{\ast }$ System and Y(4140)

Abstract

The interpretation of Y(4140) as a $D_s^{\ast }{\bar{D}}_s^{\ast }$ molecule is studied dynamically in the one boson exchange approach, where $\sigma$, $\eta$ and $\varphi$ exchange are included. Ten allowed $D_s^{\ast }{\bar{D}}_s^{\ast }$ states with low spin parity are considered, we find that the $J^{PC}=0^{++}$, $1^{+-}$, $0^{-+}$, $2^{++}$ and $1^{--}$ $D_s^{\ast }{\bar{D}}_s^{\ast }$ configurations are most tightly bound. We suggest the most favorable quantum numbers are $J^{PC}=0^{++}$ for Y(4140) as a $D_s^{\ast }{\bar{D}}_s^{\ast }$ molecule, however, $J^{PC}=0^{-+}$ and $2^{++}$ can not be excluded. We propose to search for the $1^{+-}$ and $1^{--}$ partners in the $J/\psi \eta$ and $J/\psi {\eta }^{\prime }$ final states, which is an important test of the molecular hypothesis of Y(4140) and the reasonability of our model. The $0^{++}$ $B_s^{\ast }{\bar{B}}_s^{\ast }$ molecule is deeply bound, experimental search in the ${\rm Y}(1S)\varphi$ channel at Tevatron and LHC is suggested.

Comments: 13 pages,2 figures