Another tetraquark structure in the ${\pi }^{+}{\chi }_{c1}$ invariant mass distribution

In this article, we assume that there exists a scalar hidden charm tetraquark state in the ${\pi }^{+}{\chi }_{c1}$ invariant mass distribution, and study its mass using the QCD sum rules. The numerical result $M_Z=(4.36\pm 0.18)\mathrm{G}\mathrm{e}\mathrm{V}$ is consistent with the mass of the Z(4250). The Z(4250) may be a tetraquark state, other possibilities, such as a hadro-charmonium resonance and a $D_1^{+}{\bar{D}}^0+D^{+}{\bar{D}}_1^0$ molecular state are not excluded.