un 2 00 1 Charmless final states and S – D - wave mixing in the ψ ′ ′ 1

The ψ = ψ(3770) resonance is expected to be mainly cc̄(1D1), but tensor forces and coupling to charmed particle pairs can mix it with ψ(2S1) and other states. Implications of this mixing for decays of ψ to non-charmed final states are discussed. (i) The ratio Γ(ψ → γ + χc2)/Γ(ψ′′ → γ + χc0) is expected to be highly suppressed if ψ is a pure D-wave state, and is enchanced by mixing. (ii) The expected decay ψ → ρπ and other “missing” modes can appear as corresponding ψ partial widths, enhanced by a factor depending on the mixing angle. General arguments then suggest a branching ratio of about 1%, give or take a factor of 2, for charmless hadronic decays of ψ. (iii) Enhancements can appear in penguin amplitudes in B decays, B → Kη branching ratios, and direct CP-violating asymmetries in B → Kπ decays.