Isoscalar Transition Rates in Nuclei from the (α, α′) Reaction

Abstract

Alpha-particle scattering from nuclei is known to be a predominantly surface reaction which leads to diffraction scattering (Bl 65). This information has been used to make reliable l (angular momentum transfer) assignments based on the shapes of the differential cross sections for (α, α′) reactions. However, the magnitudes (strengths) of the differential cross sections have not been related to nuclear structure in a satisfactory way despite the fact that many experiments have been performed. The major purpose of this article is to give an (approximate) relationship between the strengths of (α, α′) reactions and the matrix elements of an isoscalar (IS) multipole transition operator [defined in equation (1.4)]. The basic physical reasons for, and limitations of, this relationship are examined, and the available data are systematically presented (in terms of this relationship) along with the resulting nuclear structure information.