Abstract
Two new positron active isotopes, and , have been found to decay to excited states of and , which in turn decay "instantaneously" by alpha-emission. Their half-lives are 0.65±0.1 sec. and ¼ sec., respectively. is also found to have a low energy positron group which leads to an -unstable excited state in . The masses of and are 8.027 and 20.015, respectively. decays by a 13.7±0.3-Mev positron, through the same excited state of as does . Estimates of the energies of the excited state in and are made.
- Received 24 July 1950
DOI:https://doi.org/10.1103/PhysRev.80.519
©1950 American Physical Society