A phenomenological analysis of $\psi$ particle decays

The author uses standard ideas on meson decays (internal and spin symmetries of the quark model, and vector meson dominance) to analyse data on a large class of decays of the psi and related particles in the charm model. Finds no evidence against exact SU/sub 4/ for hadronic vertices or against vector dominance. SU/sub 4/ must then be broken in photon couplings and a systematic rule emerges. The level of consistency with experiment is suggestive that the psi behaves similarly to other hadrons.