Abstract
Background: A previous measurement of the directional coefficient in decay was used to extract recoil-order form factors. The data indicate the requirement of a significant induced-tensor matrix element for the decay. This conclusion largely relies on a standard-model-allowed weak magnetism form factor which was determined using an unpublished value of the analog branch in , with the further assumption that the transition is dominated by its isovector component.
Purpose: Our aim is to determine the width in in order to obtain an independent measurement of the weak magnetism form factor for the decay.
Methods: A resonance reaction on an implanted target was used to produce the first state in at keV. Deexcitation rays were registered with two 100% relative efficiency high purity germanium detectors.
Results: We obtain for the first time an unambiguous determination of the branch in to be .
Conclusions: Using the conserved vector current (CVC) hypothesis, our branch determines the weak magnetism form factor for decay to be . Together with the angular correlation coefficient, we obtain a large induced-tensor form factor for the decay that continues to disagree with theoretical predictions. Two plausible explanations are suggested.
1 More- Received 17 January 2017
- Corrected 3 April 2017
DOI:https://doi.org/10.1103/PhysRevC.95.035501
©2017 American Physical Society
Physics Subject Headings (PhySH)
Corrections
3 April 2017