Interaction of slow J/ψ and ψ′ with nucleons

The interaction of the charmonium resonances J/ψ and ψ′ with nucleons at low energies is considered using the multipole expansion and low-energy theorems in QCD. A lower bound is established for the relevant gluonic operator average over the nucleon. As a result we find the discussed interaction to be significantly stronger than previously estimated in the literature. In particular we conclude that the cross section of the J/ψ - nucleon elastic scattering at the threshold is very likely to exceed 17 mb and that existence of bound states of the J/ψ in light nuclei is possible. For the ψ′ resonance we estimate even larger elastic scattering cross section and also a very large cross section of the process ψ′ + N → ψ + N giving rise to the decay width of tens of MeV for the ψ′ resonance in heavy nuclei.