Analysis of the X(3872), Zc(3900), and Zc(3885) as axial-vector tetraquark states with QCD sum rules

In this article, we distinguish the charge conjunctions of the interpolating currents, calculate the contributions of the vacuum condensates up to dimension 10 in a consistent way in the operator product expansion, study the masses and pole residues of the J(PC) = 1(++/-) hidden charmed tetraquark states with the QCD sum rules, and explore the energy-scale dependence in detail for the first time. The predictions M-X = 3.87(- 0.09)(+0.09) GeV and M-Z 3.91 (+0.11) (-0.09) GeV support assigning the X(3872) and Z(c)(3900) [or Z(c)(3885)] as the 1(++) and 1(+-) diquark-antidiquark type tetraquark states, respectively.