The optical model and inelastic scattering

Abstract

Calculations of Levinson and Banerjee using the direct-interaction model for the inelastic scattering of protons indicated that the optical potential seen by the scattered particle is weaker than for the corresponding elastic scattering process. In this paper the scattering amplitude is derived and the “1/ A-corrections” to it are examined. It is shown that these represent corrections to the optical potential and arise from the requirement that the contribution of a given target nucleon to the optical potential be removed when that nucleon is interacting directly with the incident particle. It is shown that the short range, symmetry-dependence and spin-dependence of nuclear forces can make this an important correction and can explain the Levinson-Banerjee reduction. It is also shown that the strength of the effective two-body interaction, or t-matrix, is in good agreement with the strength found by Levinson and Banerjee. The distorted-wave direct-interaction model is therefore capable of predicting the absolute magnitude of the inelastic cross section.