Abstract
Background: Triplet energy differences (TED) can be studied to yield information on isospin-non-conserving interactions in nuclei.
Purpose: The systematic behavior of triplet energy differences (TED) of , states is examined. The isobar is identified as having a TED value that deviates significantly from an otherwise very consistent trend. This deviation can be attributed to the tentative assignments of the pertinent states in and .
Methods: An in-beam -ray spectroscopy experiment was performed to identify excited states in using Gamma-Ray Energy Tracking In-Beam Nuclear Array with the S800 spectrometer at NSCL using a two-nucleon knockout approach. Cross-section calculations for the knockout process and shell-model calculations have been performed to interpret the population and decay properties observed.
Results: Using the systematics as a guide, a candidate for the transition from the , state is identified. However, previous work has identified similar states with different assignments. Cross-section calculations indicate that the relevant , state should be one of the states directly populated in this reaction.
Conclusions: As spins and parities were not measurable, it is concluded that an unambiguous identification of the first , state is required to reconcile our understanding of TED systematics.
- Received 20 May 2015
- Revised 9 July 2015
DOI:https://doi.org/10.1103/PhysRevC.92.024315
©2015 American Physical Society