Energy scales and diffraction scattering

The influence of threshold on models of diffraction scattering is considered. The experimental existence of effective inelastic diffraction and baryon-antibaryon thresholds to conjecture a relation between the bare Pomeron P/sup G/ of the Gribov calculus, the bare Pomeron P/sup E/ of recent fits to NAL-ISR elastic data, and a bare Pomeron P of intercept α0 approximately equal to 0.85 utilized in medium energy two-body and high energy inclusive phenomenology. A set of energy scales is set up describing approximate regions of validity of various models for diffraction, including the Gribov calculus. An iterative approximation scheme to the s and t channel unitarity equations at small t and large s is described