Possible Molecular Explanation for the Resonance $Y(4500)$

Abstract

The BESIII collaboration has discovered a new state with hidden charm-strange. Its mass is intriguingly close to the $D_s{\bar{D}}_{s1}$ threshold and does not have the properties of the charmonium states. Working with the QCD sum rules (QCDSR) approach, we test if the charmonium-like structure $Y(4500)$, detected in the invariant mass spectrum $K^{+}{K}^{-}J/\psi$ may be interpreted as an exotic $D_s{\bar{D}}_{s1}$ molecular structure with $J^{PC}=1^{--}$. Considering the contributions of QCD condensates up to operator dimension ten, we estimate the mass and decay constant of $Y(4500)$ resonance. We get $m_Y=(4488.35\pm 11.54)$ MeV in excellent agreement with the meson mass reported by BESIII and $f_Y=(4.04\pm 0.36)\times 10^{-3}$$\mathrm{Ge}{\mathrm{V}}^4$. Our findings indicate that a pseudoscalar-axialvector molecule current can well describe this state.

Comments: 11 pages, 6 figures, 2 tables