Abstract :
The energy-dependent behavior of the absorption term of the spherical neutron optical potential for doubly magic 208Pb and neighboring 209Bi is examined. These considerations suggest a model with an intuitively attractive energy dependence of the imaginary potential that provides a good description of the observed neutron cross-sections and that is qualitatively consistent with theoretical concepts. It is an alternative to arbitrary assumptions involved in many conventional optical-model interpretations reported in the literature.
