Understanding close-lying exotic charmonia states within QCD sum rules

TL;DR

This paper uses QCD sum rules to explore the nature of exotic charmonium-like states near 4.1 GeV, focusing on their formation, spin states, and decay channels, aiding future experimental identification.

Contribution

It introduces a method to analyze spin-separated states in the $D^*_sar D^*_s$ system and predicts their masses and decay widths, advancing understanding of exotic charmonia.

Findings

Identified three nearly degenerate states around 4.1 GeV

Calculated partial decay widths to $J/eta o ext{phi}$

Provided theoretical predictions for experimental searches

Abstract

Motivated by the experimental findings of some new exotic states decaying into channels like $J/\psi \phi$, we investigate the formation of resonances/bound states in the $D^*_s\bar D^*_s$ system using QCD sum rules. To do this we start with a current of the type vector times vector and use spin projectors to separate the spin 0, 1 and 2 contributions to the correlation function. We find three states with isospin 0, nearly spin degenerate, with a mass around 4.1 GeV. We have also investigated the decay of these states to $J/\psi \phi$ and provide the corresponding partial widths. Such information should be useful for experimental studies in future.