The explanation of some exotic states in the $cs\bar{c}\bar{s}$ tetraquark system

TL;DR

This paper investigates the structure and possible resonance states of the $csar{c}ar{s}$ tetraquark system, explaining several observed exotic states through a systematic quark model analysis.

Contribution

It introduces a comprehensive study of $csar{c}ar{s}$ tetraquarks considering multiple configurations and channel couplings, identifying potential explanations for observed exotic resonances.

Findings

Identifies a molecular bound state $ar{D}_s D_s$ as a candidate for $oldsymbol{ ext{chi}_{c0}(3930)}$.

Predicts several compact tetraquark resonant states with specific masses and quantum numbers.

Suggests that observed states like $X(4350)$, $X(4500)$, and $X(4700)$ can be explained as compact tetraquarks.

Abstract

Inspired by the recent observation of $\chi_{c0}(3930)$, $X(4685)$ and $X(4630)$ by the LHCb Collaboration and some exotic resonances such as $X(4350)$, $X(4500)$, etc. by several experiment collaborations, the $cs\bar{c}\bar{s}$ tetraquark systems with $IJ^{P}=00^+$, $01^+$ and $02^+$ are systematically investigated in the framework of the quark delocalization color screening model(QDCSM). Two structures, the meson-meson and diquark-antidiquark structures, as well as the channel-coupling of all channels of these two configurations are considered in this work. The numerical results indicate that the molecular bound state $\bar{D}_{s}D_{s}$ with $IJ^{P}=00^+$ can be supposed to explain the $\chi_{c0}(3930)$. Besides, by using the stabilization method, several resonant states are obtained. There are four $IJ^{P}=00^{+}$ states around the resonance mass 4035 MeV, 4385 MeV, 4524 MeV, and 4632 MeV, respectively; one $IJ^{P}=01^{+}$ state around the resonance mass 4327 MeV; and two $IJ^{P}=02^{+}$ states around the resonance mass 4419 MeV and 4526 MeV, respectively. All of them are compact tetraquarks. Among these states, $X(4350)$, $X(4500)$ and $X(4700)$ can be explained as the compact tetraquark state with $IJ^{P}=00^{+}$, and the $X(4274)$ is possible to be a candidate of the compact tetraquark state with $IJ^{P}=01^{+}$. More experimental tests are expected to check the existence of all these possible resonance states.