Abstract
We have measured the branching ratio for the superallowed transition from to be 0.9448(8), and determined its value to be 3058.1(28) s, a result with % precision, which is a factor of 3 improvement over the previous result based on current world data. The -value ratio for the mirror pair of superallowed transitions and becomes the most precise yet measured and, in a sensitive test of the method used to calculate the isospin-symmetry-breaking correction, , it agrees well with the ratio as calculated with Woods-Saxon radial wave functions. This confirms the method used in the most recent survey of superallowed decays to extract , the up-down quark-mixing element of the Cabibbo-Kobayashi-Maskawa matrix. In addition, our branching-ratio results for the four observed Gamow-Teller branches to states in are shown to agree well with shell-model calculations based on the same effective interactions that were used in the determination of .
3 More- Received 22 January 2020
- Accepted 18 March 2020
DOI:https://doi.org/10.1103/PhysRevC.101.045501
©2020 American Physical Society