On the Origin of the $XYZ$ Mesons

TL;DR

This paper proposes a mechanism within a constituent quark model that explains the emergence of exotic $XYZ$ four-quark mesons and extends the idea to five-quark states in heavy baryons, revisiting related literature and data.

Contribution

It introduces a new mechanism for the formation of exotic $XYZ$ mesons and generalizes it to five-quark heavy baryon states, providing a unified theoretical framework.

Findings

The mechanism can produce exotic $XYZ$ states in the meson spectrum.

Extension of the mechanism to five-quark heavy baryons.

Reanalysis of experimental data supporting the mechanism.

Abstract

In this talk we present a mechanism giving rise to exotic $XYZ$ four-quark states in the meson spectra within a constituent quark model approach. We discuss its generalization to five-quark states in the heavy baryon sector. Finally, we revise some other works in the literature and experimental data where this mechanism may be working.