Hidden charm octet tetraquarks from a diquark-antidiquark model

Four exotic charmonium-like states, i.e. X(4140), X(4274), X(4500), and X(4700), have been observed very recently by LHCb Collaboration in the decay process B+ -> J/psi phi K+ using the 3fb(-1) data of p (p) over bar collision at root s = 7 and 8 TeV. In this paper, we investigate systematically the properties of hidden charm tetraquark states. The hidden charm tetraquarks form an octet configuration and a singlet configuration according to flavor SU(3) symmetry. Based on a diquark-antidiquark model, the hidden charm tetraquarks spectra are given. The previous XYZ exotic states altogether with the newly ones X(4140), X(4274), X(4500), and X(4700), can be well classified into certain representations. The spin-parities and masses of the XYZ are predicted, most of which are in agreement with the data. We particularly find that Z(c)(4430) may be treated as the first radial excitation of Zc(3900), while the Y(1(--)) states can be obtained by the first orbital excitation of the X/Z states. Besides, we calculate the decay widths of the hidden charm tetraquarks into two charmed mesons. This work gives a general tetraquark description for the XYZ states, which is helpful to uncover their inner structures