Heavy Hybrids: decay to and mixing with Heavy Quarkonium

TL;DR

This paper investigates hybrid mesons with heavy quarks, analyzing their spectrum, decay, and mixing with heavy quarkonium, and identifies potential hybrid candidates among XYZ states.

Contribution

It provides new QCD-based results on hybrid meson spectra, decay widths, and the impact of mixing with heavy quarkonium, highlighting spin symmetry breaking effects.

Findings

Hybrid mesons can significantly mix with heavy quarkonium.

Mixing may cause notable spin symmetry breaking.

Candidates for hybrid mesons are identified among XYZ states.

Abstract

We report on a recent QCD based research on hybrid mesons containing $c\bar c$ or $b\bar b$ quarks. We present results for the spectrum, the decay widths to heavy quarkonium, and the role of mixing with the latter. We point out that mixing with heavy quarkonium provides a potentially large source of spin symmetry breaking. We identify candidates to hybrid mesons among the so called XYZ states in the charmonium and bottomonium spectrum.