Disintegration ofIr192andIr194

The energies and intensities of 20 gamma rays of ${\mathrm{Ir}}^{192}$ and 16 gamma rays of ${\mathrm{Ir}}^{194}$ have been measured by studying their external conversion spectra with a high resolution beta-ray spectrometer. A Fermi analysis of the beta spectrum of ${\mathrm{Ir}}^{194}$ reveals four components with the following end-points and intensities: 2236 kev (70 percent), 1905 kev (16 percent), 975 kev (9 percent) and 430 kev (2.8 percent). The observed beta and gamma radiations are consistently accounted for in terms of transitions to the following levels of ${\mathrm{Pt}}^{194}$: 0.0, 328.1, 621, 1265, 1477, 1665, 1794, 1802, 1836, 1946, and 2048 kev. The ${\mathrm{Ir}}^{194}$-${\mathrm{Pt}}^{194}$ energy difference is 2236±10 kev. The ${\mathrm{Ir}}^{192}$ gamma-ray energies are classified in terms of levels at 0.0, 283, 485, 690, and 1064 kev in ${\mathrm{Os}}^{192}$ and 0.0, 316, 612, 784, 921, 1155, 1201, and 1359 kev in ${\mathrm{Pt}}^{192}$. The results for ${\mathrm{Ir}}^{192}$ serve chiefly as confirmation of earlier investigations.