UNIVERSAL PHASE BETWEEN STRONG AND EM INTERACTIONS

摘要

It is shown that the experimental data of ψ′ and ψ″ are consistent with a —90° phase between the strong and eletromagnetic decay amplitudes. The e~+e~- → ρπ measured at ψ″ is also consistent with the branching ratio predicted by Rosner's scenario on ρπ puzzle in charmonium decays. This scenario gets further support from a large charmless branching ratio in ψ″ decays.