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Stimulated by both new experimental data and theoretical interest, the properties of the spinsinglet P state ( ' P I ) in the c r and b6 system have been reexamined in the framework of the QCD multipole expansion. We have estimated various rates for producing $4 1 ' P , I and T( 1 ' P I ) in hadronic transitions, and for producing *( 1 ' P I I in pp annihilation. The aa mass spectrum in the transition T"-T( 1 ' P , )aa has been computed, and the two pions peak at low masses. An interesting approximation proposed by Voloshin and Zakharov is explored further in conjunction with the axial anomaly to relate many isospin-violating aO transitions involving ' p I to the known rate of 3'-J/GaO. The rates for *'-*( 1 ' P , )a0 and G( 1 ' P I )-J/*aO are found to be large. The implications are discussed.

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We propose a coherent explanation of the puzzle associated with J/y/ (y/') decays into vector plus pseudoscalar exclusive final states by assuming the general validity of the perturbative QCD hadronhelicity theorem, but supplemented by violation of this theorem when J/y/ decay to hadrons is mediated by an intermediate gluonium state O. The mass O must be within 100 MeV of the mass of the J/y/, and its total width must be less than 160 MeV. Comments are made about vector-scalar decays of J/y/ to 0S* and pS.