Abstract :
Starting from the gauge-invariant quark-antiquark Green function the expression for the nonrelativistic meson scattering amplitude on the external gluon field is obtained. The nonperturbative form of this amplitude is discussed. It is shown, that nonlocality of the nonperturbative vacuum field distribution plays an essential role. As a concrete example, the charmonium-nucleon scattering length is found and the possibility of the exotic charmonium-nucleus bound states is analyzed.
