Implications of light-quark admixtures on charmonium decays into meson pairs - art. no. 074006

We argue that charmonium decays into mason pairs fall into two distinct cla sses: one that is under control of perturbative QCD and another one that is governed by a soft mechanism. We concentrate on a systematic analysis of J /psi(Psi') decays into a Light pseudoscalar and a light vector meson and et a(c) decays into a pair of hght vector mesons. These processes belong to th e second class and are characterized by non-conserved hadronic helicity. It is assumed that, in these cases, the charmonium state decays dominantly th rough a light-quark Fock component by a soft mechanism which is characteris tic of OZI-rule allowed strong decays. Estimating the light-quark admixture by meson mixing, we obtain a reasonable description of the branching ratio s for these processes.