Stability of hexaquarks in the string limit of confinement

TL;DR

This paper investigates the stability of six-quark and three-quark–antiquark systems using a string model inspired by quantum chromodynamics, finding stable configurations for certain states and near-threshold bound states.

Contribution

It introduces a simple string model to analyze the stability of hexaquarks and related systems, extending previous tetraquark and pentaquark studies, and explores effects of mass differences on stability.

Findings

Ground state of (q^6) is stable against dissociation.

(q^3ar q{}^3) can form a bound state near threshold.

Stability depends on mass ratios in systems with different constituent masses.

Abstract

The stability of systems containing six quarks or antiquarks is studied within a simple string model inspired by the strong-coupling regime of quantum chromodynamics and used previously for tetraquarks and pentaquarks. We discuss both six-quark $(q^6)$ and three-quark--three-antiquark $ (q^3\bar q{}^3)$ states. The quarks are assumed to be distinguishable and thus not submitted to antisymmetrization. It is found that the ground state of $(q^6)$ is stable against dissociation into two isolated baryons. For the case of $ (q^3\bar q{}^3)$, our results indicate the existence of a bound state very close to the threshold. The investigations are extended to $(q^3Q^3)$ and $(Q^3\bar q^3)$ systems with two different constituent masses, and their stability is discussed as a function of the mass ratio.