Leptonic widths of high ψ-resonances in a unitary coupled-channel model
AbstractThe leptonic widths of high ψ-resonances are calculated in a coupled-channel model with unitary inelasticity, where analytical expressions for the mixing angles between (n+1)S31 and nD31 states and probabilities Zi of the cc¯ component are derived. These factors depend on energy (mass) and can be different for ψ(4040) and ψ(4160). However, our calculations give a small difference between the mixing angles, θ(ψ(4040))=(28-2+1)° and θ(ψ(4160))=(29-3+2)°, and ∼10% difference between the probabilities Z1(ψ(4040))=0.85-0.02+0.05 and Z2(ψ(4160))=0.79±0.01. It provides the leptonic widths Γee(ψ(4040))=(1.0±0.1) keV and Γee(ψ(4160))=(0.62±0.0.07) keV in agreement with experiment; for ψ(4415) the value Γee(ψ(4415))=(0.66±0.06) keV is obtained, while for the missing resonance ψ(4510), we predict its mass, M(ψ(4500))=(4512±2) MeV, and Γee(ψ(4510))=(0.68±0.14) keV.