Astrophysical evidence for the direct electron-neutrino weak interaction: Chao-wen Chin, Hong-Yee Chiu, and Richard Stothers, Institute for Space Studies, 475 Riverside Drive, New York, New York

Abstract

An approximate parameterization of an exact expression for the reflection coefficient ηl, that describes elastic scattering by a spin-independent complex potential, yields a parameterized-phase-shift model of elastic scattering. The parameterization is based on a detailed study of the role played by the nuclear surface region; the nuclear interior is regarded as a region of uniform complex potential. Surface and volume effects are represented by distinct parameters. In all, nine parameters are used. These include the depths of the real and imaginary potentials in the interior, the radius at which the interior and exterior regions join, and six “surface parameters” that modify the effects caused by the interior region. These nine parameters describe the same physics that is described by an optical potential that includes an arbitrary mixture of surface and volume interactions. This work is related to earlier work by Kikuchi, by Peaslee, and by Vogt (4).The usual results of the strong-absorption case are derived by suitable specialization of the model. A numerical example that illustrates the application of the full model is given.