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We study the photoproduction of the vector mesons $\Phi$ and $J/\Psi$ off aproton in the kinematical regime of large energies and scattering angles withinthe framework of perturbative QCD. Our investigations are based on the hardscattering approach. This means that the hadrons are replaced by their valenceFock states and scattering on the partonic level is described by tree graphs inwhich the large transferred momentum is redistributed between the valencepartons via the exchange of hard gluons. We find that the unpolarizedphotoproduction cross sections are dominated by Compton-scattering-like graphsin which the photon couples to the proton, whereas vector-meson-dominance-likegraphs, in which the photon fluctuates into the heavy quark-antiquark pairwhich then exchanges two gluons with the proton, play a minor role. We giveexplicit predictions for unpolarized scattering cross sections and compare themwith experimental data where possible.

Hard Excluseive $\Phi$ and $J/\Psi$ Photoproduction off a Proton