Diffractive hadron scattering

At very large energies diffractive reactions are crucial to understand heavy-ion collisions and other hadronic reactions. Already for proton-proton reactions the description of diffractive events is, however, still controversial, making any extrapolation to heavy ion physics very uncertain. It is proposed to clarify the basic physical mechanisms of interest by studying selective diffractive processes. The long standing problem OF the odderon contribution should be easily decidable from studies of double-diffractive. J/ψ and φ production in proton-proton and proton-antiproton collisions. The importance of double-diffractive processes for exotic particle production like e.g. the production of Higgs particles is discussed. (author) 15 refs.; 7 figs