Role of shielding cuts in high-energy diffraction scattering

Regularities of high-energy diffraction scattering emerging from the experimental investigation of pp, πp and Kp scatterings are discussed in the context of a model with a shielded pomeron. In this model, exchange degeneracy of secondary trajectories is valid over a wide energy range and the leading singularities in the j-plane are factorizable. The pomeron singularity is essentially a SU3 singlet. SU3 breaking at medium-high energies is attributed to a nearby singularity, namely the shielding cut. An important consequence of the present model is the prediction that the structure observed in the pp angular distribution at low |t| values should be absent in the diffraction peak in K+p scattering. Finally, on the basis of the singularity structure in the model, it is argued that the energy dependence of the diffraction slopes is consistent with the observed behaviour of the respective total cross-sections. (author)