Analysis of the hidden-charm tetraquark molecule mass spectrum with the QCD sum rules

TL;DR

This paper uses QCD sum rules to analyze the mass spectrum of hidden-charm tetraquark molecular states, including strange and hidden-strange variants, and revisits the classification of X, Y, Z states as tetraquark molecules.

Contribution

It provides a comprehensive QCD sum rule analysis of various hidden-charm tetraquark molecular states and reassesses their connection to observed exotic mesons.

Findings

Mass spectrum predictions for hidden-charm tetraquark molecules

Revised assignments of X, Y, Z states as molecular tetraquarks

Consistent theoretical framework for tetraquark molecular states

Abstract

In this article, we investigate the mass spectrum of the ground state hidden-charm tetraquark molecular states without strange, with strange and with hidden-strange via the QCD sum rules in a comprehensive way and revisit the assignments of the $X$, $Y$, $Z$ states in the scenario of tetraquark molecular states consistently based on the QCD sum rules.