In this article, we assume that there exist hidden charmed tetraquark states with the spin-parity $J^P=1^-$, and calculate their masses with the QCD sum rules. The numerical result indicates that the masses of the vector hidden charmed tetraquark states are about $M_{ Z}=(5.12\pm0.15) \rm{ GeV}$ or $M_{ Z}=(5.16\pm0.16) \rm{ GeV}$, which are inconsistent with the experimental data on the $\pi^+ \chi_{ c1}$ invariant mass distribution. The hidden charmed mesons $Z_1$, $Z_2$ or $Z$ may be scalar hidden charmed tetraquark states, hadro-charmonium resonances or molecular states.
Categories: hep-ph