STUDY OF THE Pt$sup 189$ $Yields$ Ir$sup 189$ $Yields$ Os$sup 189$ DECAY CHAIN

Permanent magnet electron spectrographs, a doublefocusing electron spectrometer, and gamma-scintillation spectrometers were used to measure the energies and intensities of radiations that accompany the decay of /sup 189/Pt. From these data, the conversion coefficients, multipolarities, and mixing ratios of a number of the transitions were determined. Some new transitions are reported, and a revised level scheme, incorporating all but one of the observed transitions, is proposed for /sup 189/Ir. A half life of 10.87 plus or minus 0.12 h was determined for /sup 189/Pt. The gammascintillation spectrum obtained from a pure source of /sup 189/Ir is reported. The half life of /sup 189/Ir is 13.3 plus or minus 0.1 days. (auth)