Saturation of coupling of collective levels in optical model calculations of even-even actinides

Abstract

Saturation of the coupling-scheme is studied in dispersive optical model calculations of nucleon induced reactions on 238U target. Recently derived potential that is based on a soft-rotator-model (SRM) description of the collective levels of the target nucleus with volume conservation is used. It is show that calculated direct excitation cross sections of all considered non-GS bands levels are larger than the 4+ GS band level excitation, and can't be ignored in coupled-channel calculations. SRM couplings of 21 levels constitute a saturated coupling scheme that allows a precise calculation of the compound-nucleus (CN) formation cross sections up to several MeV.