Widths of Isobaric Analog Resonances: a microscopic approach

Abstract

A self-consistent particle-phonon coupling model is used to investigate the properties of the isobaric analog resonance in ${}^{208}$Bi. It is shown that quantitative agreement with experimental data for the energy and the width can be obtained if the effects of isospin-breaking nuclear forces are included, in addition to the Coulomb force effects. A connection between microscopic model predictions and doorway state approaches which make use of the isovector monopole resonance, is established via a phenomenological ansatz for the optical potential.

18 pages, 1 figure. To appear on Phys. Rev. C (tentatively scheduled for June 1998)