Abstract
By using delayed coincidence techniques, the mass excesses of and have been measured to be -24 546 ± 45 and -20 569 ± 50 keV, respectively, representing improvements in precision of a factor of 2 for and a factor of 4 for over previous measurements. The first measurements of the high-energy rays from decay with a Ge(Li) detector are presented, revealing three new branches. -ray energies (in keV) and relative intensities for the daughter transitions are 1787 ± 1 (0.30 ± 0.10), 1947.1 ± 1.5 (0.28 ± 0.10), 1987.2 ± 1.0 (1.0 ± 0.2), 2127.4 (100.0 ± 0.3), 4073.4 ± 1.5 (0.46 ± 0.06), and 4114.0 ± 1.5 (1.2 ± 0.2). The excitation energies and relative branches are 2127.4 (100 ± 0.3), 3303.7 (<0.26), 3914.2 (0.30 ± 0.10), 4073.0 (0.76 ± 0.12), and 4114.5 (2.2 ± 0.3). For the decay of , energies and relative intensities of rays were measured to be 415.8 ± 0.6 (6.7 ± 0.6), 1431.4 (13.1 ± 1.0), 1847.5 (100 ± 1), and 2537.5 (9.3 ± 0.8), representing excitation energies and relative -ray intensities to the daughter states of 1431.4 (), 1847.5 (), and 2537.6 (10.5 ± 1.0). The half-lives of and were determined by multiscaling -ray yields to be 12.45 ± 0.10 and 6.11 ± 0.21 sec, respectively. Combined with an earlier result, a half-life of 6.18 ± 0.18 sec is adopted for . The transverse mass relationship of Garvey, using the present measurements for and , predicts a mass excess of -20 251 ± 90 keV for the nuclide .
- Received 18 June 1973
DOI:https://doi.org/10.1103/PhysRevC.8.1324
©1973 American Physical Society