Radiative decays $J/\Psi \to {\eta }^{(\prime )}\gamma$ in perturbative QCD

Abstract

With the recent investigations of $g^{\ast }{g}^{\ast }-{\eta }^{(\prime )}$ transition form factor and $\eta -{\eta }^{\prime }$ mixing scheme, we present an updated study of the radiative decays $J/\Psi \to {\eta }^{(\prime )}\gamma$ in perturbative QCD. The decays are taken as a test ground for the $g^{\ast }{g}^{\ast }-{\eta }^{(\prime )}$ transition form factors and the $\eta -{\eta }^{\prime }$ mixing scheme. The form factors are found to be working for glunic ${\eta }^{(\prime )}$ productions and the mixing angle is constrained to be $\varphi =35.1^{\circ }\pm 0.8^{\circ }$.

Comments: 10 pages, 2 eps figures