Anomalies, $\eta$ , $\eta$' as keys to glueballs

Abstract

Glueballs are the most straightforward prediction of QCD, yet while they have likely been produced, none has been unequivocally identified. We pursue a backdoor approach through anomalies, and singularly the $\eta$ and $\eta$' which brings light to this irritating situation. In particular, we advocate to consider the full decay chain $J/\psi \to X\gamma ,X\to \eta {\eta }^{\prime }$ (into glue-rich states followed by glue-rich decays). We also suggest new BES III searches, namely for the ${\pi }_1$ into $\eta {(}^{\prime }){\pi }^0$, (this would be the partner of their recently observed ${\eta }_1(1855)$). Another useful investigation would be for other channels (or semi-inclusive) $f_0(1500)$ decays (see last section)

Comments: Corfu workshop proceedings 2022