Charm production in antiproton-nucleus collisions at the J/ψ and the ψ′ thresholds

We discuss the production of charmonium states in antiproton-nucleus collisions at the ψ′ threshold. It is explained that measurements in p̄A collisions will allow to get new information about the strengths of the inelastic J/ψN and ψ′N interaction, on the production of Λ_c and D̄ in charmonium-nucleon interactions and for the first time about the nondiagonal transitions ψ′N→J/ψN. The inelastic J/ψ-nucleon cross section is extracted from the comparison of hadron-nucleus collisions with hadron-nucleon collisions. We extract the total J/ψ-nucleon cross section from photon-nucleon collisions by accounting for the color transparency phenomenon within the frame of the GVDM (generalized vector meson dominance model). We evaluate within the GVDM the inelastic ψ′-nucleon cross section as well as the cross section for the nondiagonal transitions. Predictions for the ratio of J/ψ to ψ′ yields in antiproton-nucleus scatterings close to the threshold of ψ′ production for different nuclear targets are presented.