Superallowed Beta Decay of Nuclei with A >or= 62: The Limiting Effect of Weak Gamow-Teller Branches
Nuclear Theory
2009-11-10 v1
Abstract
The most precise value of V_{ud}, which is obtained from superallowed nuclear beta decay, leads to a violation of CKM unitarity by 2.2 sigma. Experiments are underway on two continents to test and improve this result through decay studies of odd-odd N = Z nuclei with A >or= 62. We show, in a series of illustrative shell-model calculations, that numerous weak Gamow-Teller branches are expected to compete with the superallowed branch in each of these nuclei. Though the total Gamow-Teller strength is significant, many of the individual branches will be unobservably weak. Thus, new techniques must be developed if reliable ft-values are to be obtained with 0.1% precision for the superallowed branches.
Cite
@article{arxiv.nucl-th/0308005,
title = {Superallowed Beta Decay of Nuclei with A >or= 62: The Limiting Effect of Weak Gamow-Teller Branches},
author = {J. C. Hardy and I. S. Towner},
journal= {arXiv preprint arXiv:nucl-th/0308005},
year = {2009}
}
Comments
4 pages, 1 figure. revtex4