The diffraction pattern of pp elastic scattering and the composite structure of the proton

The consequences of the quark-glue structure of hadrons for pp elastic scattering are examined in a simple model where the glue is taken to be the active constituent in normal (low p/sub T/) hadronic collisions. Earlier work based on the study of pp inelastic diffraction concluded that the glue-glue elastic amplitude t/sub g/ is approximately Gaussian in the glue-glue impact parameter b/sub g/, with maximum opacity at b/sub g/=0. A slight refinement of this approximation, in which t/sub g/ is almost maximally opaque over a small b/sub g/ interval and is Gaussian at larger b/sub g/, is shown to account for the remarkable diffraction structure observed in pp elastic scattering at ISR energies. A simple form is obtained for the form factor describing the impact parameter distribution of the glue inside a proton. (8 refs).