Anomalous interactions between mesons with nonzero spin and glueballs

TL;DR

This paper investigates anomalous interactions of higher-spin mesons and glueballs, revealing how instanton effects influence mixing angles and decay channels, and suggesting the gluonic nature of the X(2600) state.

Contribution

It extends the study of anomalous interactions to higher-spin mesons and glueballs, providing new insights into their mixing and decay properties.

Findings

Mixing angle decreases and oscillates with increasing spin.

Anomalous interactions enable rare decay channels.

X(2600) likely has a gluonic component.

Abstract

Topologically nontrivial fluctuations control the anomalous interactions for the $\eta$ and and $\eta \prime$ pseudoscalar mesons. We consider the anomalous interactions for mesons with higher spin, the heterochiral nonets with $J^{P C} = 1^{+ -}$ and $2^{- +}$. Under the approximation of a dilute gas of instantons, the mixing angle between non-strange and strange mesons decreases strongly as $J$ increases, and oscillates in sign. Anomalous interactions also open up new, rare decay channels. For glueballs, anomalous interactions indicate that the $X(2600)$ state is primarily gluonic.