Hidden charm octet tetraquarks from a diquark-antidiquark model

TL;DR

This paper models hidden charm tetraquarks as diquark-antidiquark states within an SU(3) flavor symmetry framework, classifying known XYZ states and predicting their properties and decay behaviors.

Contribution

It provides a systematic classification and spectral predictions of hidden charm tetraquarks, including new insights into XYZ states using a diquark-antidiquark model.

Findings

XYZ states fit into SU(3) multiplets

Predicted masses and spin-parities align with experimental data

Identified Zc(4430) as a radial excitation of Zc(3900)

Abstract

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 $B^+\to J/\psi \phi K^+$ using the 3${\rm fb}^{-1}$ data of $p\bar p$ collision at $\sqrt s= 7$ 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 $Z_c(3900)$, 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.