QCD Anomaly Coupling for the $\eta'-g-g$ Vertex in Inclusive Decay $B\to\eta' X_s$

TL;DR

This paper models the QCD anomaly coupling of the $ ext{eta'}$ meson to gluons and photons using the axial vector current triangle anomaly, providing predictions consistent with experimental decay data.

Contribution

It introduces a unified approach to calculate the QCD and QED anomalies of the $ ext{eta'}$ meson using a single parameter, improving understanding of its decay processes.

Findings

Predicted branching ratios align with experimental data.

Consistent calculation of QCD and QED anomalies using one parameter.

Enhanced understanding of $ ext{eta'}$ decay mechanisms.

Abstract

The QCD anomaly coupling of $\eta'-g-g$ is treated as the axial vector current triangle anomaly. By assuming the divergent axial vector coupling of the $\eta'$ meson with the quark line in the triangle diagram, we calculate the QCD anomaly of $\eta'-g-g$ as well as the QED anomaly of $\eta'-\gamma-\gamma$ with only one common parameter $\kappa_{\eta'}$. We obtain consistent results of the branching ratios for $B\to\eta' X_s, J/\psi\to\eta'\gamma$ and $\eta'\to \gamma\gamma$ when comparing with experimental data.