Eta' gluonic content and J/psi->VP decays

Abstract

The $\eta$-${\eta }^{\prime }$ pseudoscalar mixing angle and the gluonium content of the ${\eta }^{\prime }$ meson are deduced from an updated phenomenological analysis of $J/\psi$ decays into a vector and a pseudoscalar meson. The values for the mixing angle and the gluonic content of the ${\eta }^{\prime }$ wave function are ${\varphi }_P=(44.5\pm 4.3{)}^{\circ }$ and $Z_{{\eta }^{\prime }}^2=0.28\pm 0.21$, respectively.

Comments: 5 pages, uses espcrc2 style. Talk presented at the International Workshop on e+e- collisions from Phi to Psi (PHIPSI08), Laboratori Nazionali di Frascati (Rome), Italy, 7-10 April 2008