  The leptonic widths of high $\psi$-resonances are calculated in a
coupled-channel model with unitary inelasticity, where analytical expressions
for mixing angles between $(n+1)\,^3S_1$ and $n\,^3D_1$ states and
probabilities $Z_i$ of the $c\bar c$ component are derived. Since these factors
depend on energy (mass), different values of mixing angles
$\theta(\psi(4040))=27.7^\circ$ and $\theta(\psi(4160))=29.5^\circ$,
$Z_1\,(\psi(4040))=0.76$, and $Z_2\,(\psi(4160))=0.62$ are obtained. It gives
the leptonic widths $\Gamma_{ee}(\psi(4040))=Z_1\, 1.17=0.89$~keV,
$\Gamma_{ee}(\psi(4160))=Z_2\, 0.76=0.47$~keV in good agreement with
experiment. For $\psi(4415)$ the leptonic width
$\Gamma_{ee}(\psi(4415))=~0.55$~keV is calculated, while for the missing
resonance $\psi(4510)$ we predict $M(\psi(4500))=(4515\pm 5)$~MeV and
$\Gamma_{ee}(\psi(4510)) \cong 0.50$~keV.

High Energy Physics - Phenomenology;High Energy Physics - Experiment