Radiative VPgamma transitions and eta-eta' mixing

Abstract

A value for the $η$-$η^\prime$ mixing angle is extracted from the data on $VPγ$ transitions using simple quark-model ideas. The set of data covers {\it all} possible radiative transitions between the pseudoscalar and vector meson nonets. Two main ingredients of the model are the introduction of flavour-dependent overlaps for the various $q\bar{q}$ wave functions and the use of the quark-flavour basis to describe the $η$-$η^\prime$ system. In this basis the mixing angle is found to be $ϕ_P=(37.7\pm 2.4)^\circ$.