Separable Representation of Proton-Nucleus Optical Potentials

Recently, a new approach for solving the three-body problem for (d,p) reactions in the Coulomb-distorted basis in momentum space was proposed. Important input quantities for such calculations are the scattering matrix elements for proton-(neutron-) nucleus scattering. We present a generalization of the the Ernst-Shakin-Thaler scheme in which a momentum space separable representation of proton-nucleus scattering matrix elements in the Coulomb basis can be calculated. The success of this method is demonstrated by comparing S-matrix elements and cross sections for proton scattering from C-12, Ca-48, and Pb-208 with the corresponding coordinate space calculations.