B to eta' + X and The QCD Anomaly

Abstract

Mechanisms for the observed large $Br(B \to η' +X_s)$ are examined. We propose that the dominant fraction of the $B \to η' +X_s$ rate is due mainly to $b \to s g^*$, where $g^*$ is an off-shell gluon, followed by $g^* \to gη'$ via the anomalous coupling of the $η'$ to two gluons. The calculated rate for $B \to η'+X_s$ is in rough accord with experiment using a fairly constant glue-glue-$η'$ form factor. This behavior of the form factor may be indicative of glueball dominance of the channel. Searches via the modes $η' h^+h^-$ ($h=π$ or $K$) may be worthwhile. Charmonia contributions [i.e $B \to η_c, ψ(\to η'+X) +X_s$] can only account for at most 20% of the central value of the signal. Implications for $B \to η' +X_d$ and for the corresponding $η$ modes are also given.