The imaginary part of the heavy ion optical potential

Abstract

A number of different methods have been proposed for calculating the imaginary part of the Heavy-Ion Optical potential. In some of these a folding type procedure is used. Real and imaginary parts of the optical potential come from folding of the real and imaginary parts of some effective nucleon-nucleon t-matrix with nuclear densities. Another procedure calculates the loss of flux from the incident channel in second order perturbation theory. Green’s function methods give a way of improving the perturbation approach.In this lecture a different approach based on Feynman’s path integral method is proposed. It is known that semi-classical methods are very useful for calculating heavy-ion scattering. The Feynman method provides a natural link between a complete quantal theory and semi-classical approximations. By writing a path integral expression for the scattering amplitude one obtains a formula relating the imaginary part of the optical potential to the coupling of the elastic channel to various inelastic and reaction channels. In a perturbation approximation this formula is quite analogous to Feshbach’s formula which has been used recently to obtain a long-range optical potential describing the effects of Coulomb excitation on elastic scattering.KeywordsElastic ScatteringOptical PotentialCoulomb BarrierInteract NucleusFolding ModelThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.