Υ(1s)-->γ(η',η) decays

Abstract

The decays of ${\rm Y}(1s)\to \gamma ({\eta }^{\prime },\eta )$ are studied by an approach which has successfully predicted the ratio $\frac{\Gamma (J/\psi \to \gamma {\eta }^{\prime })}{\Gamma (J/\psi \to \gamma \eta )}$. Strong dependence on quark mass has been found in the decays $(J/\psi ,{\rm Y}(1s))\to \gamma ({\eta }^{\prime },\eta )$. Very small decay rates of ${\rm Y}(1s)\to \gamma ({\eta }^{\prime },\eta )$ are predicted.

8 pages