Decays of J/ψ and ψ′ into vector and pseudoscalar mesons and the pseudoscalar glueball– mixing

Abstract

We introduce a parametrization scheme for J/ψ(ψ′) → VP where the effects of SU(3) flavor symmetry breaking and doubly OZI-rule violation (DOZI) can be parametrized by certain parameters with explicit physical interpretations. This scheme can be used to clarify the glueball– mixing within the pseudoscalar mesons. We also include the contributions from the electromagnetic (EM) decays of J/ψ and ψ′ via J/ψ(ψ′) → γ* → VP. Via study of the isospin violated channels, such as J/ψ(ψ′) → ρη, ρη′, ωπ0 and ϕπ0, reasonable constraints on the EM decay contributions are obtained. With up-to-date experimental data for J/ψ(ψ′) → VP, J/ψ(ψ′) → γP and P → γγ, etc, we arrive at a consistent description of the mentioned processes with a minimal set of parameters. As a consequence, we find that there exists an overall suppression of the ψ′ → 3g form factors, which sheds some light on the long-standing ‘ρπ puzzle’. By determining the glueball components inside the pseudoscalar η and η′ in three different glueball– mixing schemes, we deduce that the lowest pseudoscalar glueball, if it exists, has a rather small component, and it makes η(1405) a preferable candidate for a 0−+ glueball.