Decay Scheme ofPt199

The radiations of the 30-min activity of ${\mathrm{Pt}}^{199}$ have been investigated with 180° magnetic photographic spectrometers and a 10-channel coincidence scintillation spectrometer. This activity of platinum has been found to decay by the emission of four beta rays with maximum energies of 0.8, 1.1, 1.3, and 1.7 Mev. Gamma rays with energies of 0.074, 0.197, 0.246, 0.318, 0.475, 0.54, 0.71, 0.79, and 0.96 Mev were detected. Extensive beta-gamma and gamma-gamma coincidence measurements were made; and an energy level scheme is proposed which is consistent with the results of all of the experiments.