Shell Model as a Unified View of Nuclear Structure

Shell-model half-lives for r-process waiting point nuclei including first-forbidden contributions

10 oct. 2012, 12:00

25m

Amphi Gruenwald (Institut Pluridisciplinaire Hubert Curien)

Recent progress in the nuclear shell model and other approaches to nuclear structure Recent progress in shell model and other approaches to nuclear structure

Orateur

Dr Qijun Zhi (TU Darmstadt)

Description

We have performed large-scale shell-model calculations of the half-lives and neutron-branching probabilities of the r-process waiting point nuclei at the magic neutron numbers N=50, 82, and 126. The calculations include contributions from allowed Gamow-Teller and, for the first time, also from first-forbidden transitions. We find good agreement with the measured half-lives for the N=50 nuclei with charge numbers Z=28-32 and for the N=82 nuclei 129Ag and 130Cd. The contribution of forbidden transitions reduce the half-lives of the N=126 waiting point nuclei significantly, while they have only a small effect on the half-lives of the N=50 and 82 r-process nuclei. We also discuss the kexi approximation used in FF transitions and found that it is not a very good approximation when FF should be considered in the half lives.

Documents de présentation

Transparents

ZHI.pdf