Glueball Physics in QCD

TL;DR

This paper presents a new perspective on glueball physics in QCD using Abelian decomposition, predicting hybrid hadrons and providing a framework for experimental searches of glueballs and their mixing with quarkonia.

Contribution

It introduces a novel decomposition of QCD that simplifies the dynamics and extends the quark model to include valence gluons, offering new insights into glueballs and hybrid hadrons.

Findings

Systematic search strategy for ground state glueballs below 2 GeV.

Predictions of glueball-quarkonium mixing patterns.

Branching ratios for radiative decays of ψ to glueball states.

Abstract

The Abelian decomposition of QCD which decomposes the gluons to the color neutral binding gluons and the colored valence gluons shows that QCD can be viewed as the restricted QCD (RCD) made of the binding gluons which has the valence gluons as colored source, and simplifies the QCD dynamics greatly. In particular, it tells that the gauge covariant valence gluons can be treated as the constituents of hadrons, and generalizes the quark model to the quark and valence gluon model. So it provides a comprehensive picture of glueballs and their mixing with quarkoniums, and predicts new hybrid hadrons made of quarks and valence gluons. We discuss how these predictions could be confirmed experimentally. In particular we present a systematic search for the ground state glueballs and their mixing with quarkoniums below 2 GeV in $0^{++}$, $2^{++}$, and $0^{-+}$ channels within the framework of QCD, and predict the relative branching ratios of the radiative decay of $\psi$ to the physical states.