Abstract
The ratio of and -ray branches to the 4.44-MeV excited state of was measured by detecting rays in a plastic scintillator and rays in two Ge(Li) detectors. Activities were made in the and reactions using a chopped Van de Graaff beam. Data were stored in two successive computer time bins of two half-lives each in order to establish by subtraction the shape of the short-lived -ray spectrum and its net number of counts. The ratio of these branches was found to be / = 1.56±0.05. A measurement of the absolute -ray branch to the 4.44-MeV state via coincidences using an NaI(T1) detector for the rays gave a value of 1.276±0.050%. Half-lives, obtained by multiscaling -ray counts, were found to be 20.20±0.02 msec for and 11.000±0.016 msec for . The mirror asymmetries derived from these results are for the decay to the 4.44-MeV state of and for the branch to the ground state.
[RADIOACTIVITY , : Measured , , coin, ; deduced -ray branches, mirror asymmetries.]
- Received 17 August 1977
DOI:https://doi.org/10.1103/PhysRevC.17.280
©1978 American Physical Society