Sexaquarks and $H$ dibaryons in the $uuddss$ system: a comparison within a constituent quark model

TL;DR

This study uses a constituent quark model and diffusion Monte Carlo to analyze the $uuddss$ multiquark system, comparing a fully antisymmetric sexaquark configuration with a baryon-baryon-like $H$ dibaryon structure.

Contribution

It provides a detailed comparison of two multiquark configurations within a constituent quark model, highlighting their mass spectra and internal structures.

Findings

States with baryon-baryon-like configurations are near the two-baryon threshold.

Loosely bound three-quark clusters are separated by about 2.5 fm.

Remaining structures are compact regardless of internal wavefunction.

Abstract

We study the $uuddss$ multiquark within a constituent quark model framework, solving the corresponding nonrelativistic Schrodinger equation by means of a diffusion Monte Carlo (DMC) method. The total wavefunction is written as the product of a radial component and an exact spin-color-flavor state, restricted to isospin $I$=0. For this isospin, all allowed flavor wave functions are included. We explore two distinct constructions of the six-quark system. In the first one, corresponding to a sexaquark, all six quarks are treated as indistinguishable and the wave function is fully antisymmetric with respect to the exchange of any two quarks. In the second one, corresponding to the $H$ dibaryon, the system is partitioned into two sets of three quarks, effectively mimicking a baryon-baryon-like configuration including hidden color terms in which antisymmetry is imposed only within each three-quark cluster. Only when the system is forced into a baryon-baryon-like configuration, and for certain values of the spin, color and flavor quantum numbers, do we obtain states with masses close to, but above, the two-baryon threshold. Those states are characterized by two loosely bound three-quark clusters separated from one another by a distance of $\sim$ 2.5 fm. The remaining structures are compact objects irrespectively of their internal wavefunction.