Abstract
A study has been made of the properties and decay modes of the 146-keV and 68-keV excited states of populated by electron capture in . Relative 78-, 68-, and 146-keV -ray intensities are found to be 106.2, 100, and 0.10, respectively. Absolute -shell internal conversion coefficients and have been determined. The factor of the 68-keV state has been measured by a magnetically perturbed angular-correlation experiment as +0.342±0.006. admixtures and have been deduced from angular-correlation results and the conversion measurements. A (1.9±1.5)% electron-capture branch to the 68-keV state has been observed. Spin and parity assignments of 1+, 1+, and 2+ are most probable for the 146-keV, 68-keV, and ground states of . A remarkably large hindrance factor (≥6.6×) is determined for the 146-keV transition. All other and transition rates are strongly hindered except for the component of the 68-keV transition, for which an enhancement of 16 is observed.
- Received 11 August 1966
DOI:https://doi.org/10.1103/PhysRev.153.1209
©1967 American Physical Society