Nucleon-nucleon high-energy scattering

The high energy pn charge exchange and pp elastic scattering reactions are studied in an effective hadron model for the energy range of s ∼ 50 to 400 GeV2. The main features of the observed differential cross section of the pn charge exchange reaction, the forward peak and the scaling behavior over the large energy range, are well reproduced by a combination of π-, ρ-exchange and a 4-Nucleon contact term. The latter acts as a background field which turns out to be naturally suppressed in elastic NN scattering but contributes significantly to the charge-exchange reaction.