QCD quark cyclobutadiene and light tetraquark spectrum

TL;DR

This paper introduces a novel ring-like QCD tetraquark structure called quark cyclobutadiene, studies its properties using the flux tube model, and predicts its spectrum and relevance to experimental states.

Contribution

It proposes the QCD quark cyclobutadiene structure and analyzes its spectrum, providing new insights into tetraquark configurations and their experimental implications.

Findings

QCD quark cyclobutadiene is energetically similar to other flux tube structures.

Many experimental tetraquark candidates have masses close to the calculated values.

Predicted isotensor states with specific quantum numbers around 1500 MeV.

Abstract

The QCD quark cyclobutadiene (ring-like), a new color structure of tetraquark system, is proposed and studied in the flux tube model with multi-body confinement potential. The QCD quark cyclobutadiene and other flux tube structures of tetraquark states have similar energies and they can be regarded as QCD isomeric compounds. The light tetraquark spectra ($u, d, s$ only) with ring-like and diquark-antidiquark structures are calculated in the flux tube model. The results show that many experimental states have the masses close to the calculated values if they are taken as tetraquark states. The isotensor states with $J^{PC}=1^{--}$ and $J^{PC}=2^{++}$ are studied and predicted that the masses are around 1500 MeV. The multi-body interaction plays a important role to reduce the energy of the multiquark state.