Two-body strong decays of the hidden-charm tetraquark molecular states via the QCD sum rules

In this work, we extend our previous work on the $D^{\ast }{\bar{D}}^{\ast }$ molecular states with the $J^{PC}=0^{++}$, $1^{+-}$ and $2^{++}$ to investigate their two-body strong decays via the QCD sum rules based on rigorous quark-hadron duality. We obtain the partial decay widths therefore total widths of the ground states with the $J^{PC}=0^{++}$, $1^{+-}$ and $2^{++}$, which indicate that it is reasonable to assign the $X_2(4014)$ as the $D^{\ast }{\bar{D}}^{\ast }$ tetraquark molecular states with the $J^{PC}=2^{++}$.