An analysis of elastic scattering reactions with a Fermi-Dirac pomeron opaqueness in impact parameter space

In the Bourrely-Soffer-Wu model (BSW) we introduce for the pomeron a new opaqueness in impact parameter space in terms of different quark contributions described by a Fermi-Dirac distribution. In order to check the validity of this assumption we consider $p~p$, $\bar p~p$, and $\pi^{\pm}~p$ elastic scattering. We emphasize the role of the gluon above the diffraction peak in the differential cross sections. Once these contributions are determined we extend the model to light nuclei elastic reactions like $p~d$, $p~^4\mbox{He}$ and $\pi^{\pm}~^4\mbox{He}$. The results obtained show a good description of all these elastic processes over the available experimental energy range and moderate momentum transfer.