Abstract
The gamma-ray and conversion-electron spectra accompanying the decay of 4.0-day have been studied using a lithium-drifted germanium detector, permanent-magnet spectrographs, and an orange beta-ray spectrometer. Strong transitions with indicated multipolarities have been found at , , , , and keV; weaker transitions have been observed at 55.82, 139.72, 151.55, and keV. The level scheme of odd-odd has been elucidated, using conversion electron--ray coincidence measurements. Levels in are indicated at 0 (1-), 32.70 (2-), 74.79 (2+), 158.77 (1+), and 214.6 (+) keV. Delayed-coincidence events were observed between the strong 74.77- and 84.00-keV transitions, indicating a lifetime of 0.18±0.02 μsec for the 74.79-keV level in . It is suggested that two different proton configurations and contribute to the positive- and negative-parity states, respectively. Proton and neutron shell-model configurations are suggested for several levels. A -coupling model is used to interpret the spins and parities of the observed levels.
- Received 27 January 1965
DOI:https://doi.org/10.1103/PhysRev.138.B1017
©1965 American Physical Society