The theoretical mechanisms for the decays ψ′ → ψπ0 and ψ′ → ψη, which violate SU2 and SU3, respectively discussed. It is argued that symmetry breaking in the decay amplitudes may be as important as π0 -η -η′ mixing. The π0 -η mechanism ψ′ → ψν → ψπ0 leads to Γ(ψ′ → ψπ0) = (3.3±1.0) × 10-3 Γ(ψ′ → ψν), but this number may be enhanced by a factor as large as 12 by π0-η′ mixing and isospin violation in the decay amplitude. The related decays ψ → ηγ and ψ → η′γ are also discussed.
All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics