Phenomenology of high-momentum-transfer elastic processes

An analysis is carried out to extract the leading effective trajectories and residues in pp and ..pi../sup -/p elastic scattering. The results are compared with the predictions of the constituent-interchange model and the logarithmic dual model, which are shown to be the only two types of theory capable of providing a uniform link between backward and forward Regge regions and the fixed-angle region. The hypothesis of a smooth connection between forward and backward Regge regions puts strong contraints on a priori unrelated trajectories and residues. The possibility of a connection between the two models is discussed. As expected from interchange theory the extracted ..pi../sup -/p trajectory and residue behave quite differently than those for pp. The dual model seems to give the best overall description of the pp trajectory and residue functions while the ..pi..p results agree completely with the interchange predictions. The two model fits to pp elastic scattering at moderate energies (12--24 GeV) are used to extract an expected Pomeron term. The shape of the extracted diffractive contribution is strikingly similar to the recent CERN ISR differential cross sections which exhibit a dip at t = - 1.4 GeV/sup 2/ and a slow falloff in the large-t region.