The photon structure and exclusive production of vector mesons in γγ collisions

The process of exclusive vector meson production, gamma gamma --> J/psi rho (nu), is studied for almost real photons. This process may be reduced to the photoproduction of J/psi off the rho (0) meson. We discuss the possibility of extracting the gluon distribution of rho (0) and of the photon from such a measurement. Predictions are also given for the reaction e(+)e(-) --> e(+)e(-) J/psi rho (0) for various e(+)e(-) cms energies typical for LEP and for the future linear colliders.