$X(4140)$, $X(4270)$, $X(4500)$ and $X(4700)$ and their   $cs\bar{c}\bar{s}$ tetraquark partners
  In the simple color-magnetic interaction model, we investigate possible ground $cs\bar{c}\bar{s}$ tetraquark states in the diquark-antidiquark basis. We use several methods to estimate the mass spectrum and discuss possible assignment for the $X$ states observed in the $J/\psi\phi$ channel. We find that assigning the Belle $X(4350)$ as a $0^{++}$ tetraquark is consistent with the tetraquark interpretation for the $X(4140)$ and $X(4270)$ while the interpretation of the $X(4500)$ and $X(4700)$ needs orbital or radial excitation. There probably exist several tetraquarks around 4.3 GeV that decay into $J/\psi\phi$ or $\eta_c\phi$. 
Jing Wu, Yan-Rui Liu, Kan Chen, Xiang Liu, Shi-Lin Zhu
hep-ph hep-ex hep-lat nucl-ex nucl-th