J ψ → vector + pseudoscalar decays and the quark content of η and η ′

Branching ratios of {ital J}/{psi} decays into {omega}{pi}{sup 0},{omega}{eta},{omega}{eta}{prime},{rho}{eta},{rho}{eta}{prime},{phi}{eta},{phi}{eta}{prime}, and {ital K}{sup *}(892){bar K}+charge conjugate are measured from the 8.6{times}10{sup 6} {ital J}/{psi}'s produced by the DM2 experiment at the Orsay {ital e}{sup +}{ital e}{sup {minus}} storage ring DCI. The {eta} and {eta}{prime} mesons are found consistent with a {ital q{bar q}} structure and a mixing angle {theta}{sub {ital P}}=({minus}19.1{plus minus}1.4){degree}.