Radiations from ${\mathrm{Os}}^{185}$, ${\mathrm{Os}}^{191}$, and ${\mathrm{Os}}^{193}$

The radiations from ${\mathrm{Os}}^{185}$ (97 days), ${\mathrm{Os}}^{191}$ (32 hr.) and ${\mathrm{Os}}^{193}$ (15 days) have been investigated with the help of a magnetic lens spectrometer. ${\mathrm{Os}}^{185}$ decays by orbital electron capture accompanied by two gamma-rays of energy 0.648 and 0.878 Mev. The number of gamma-ray quanta of 0.648 Mev is six times that of 0.878 Mev. ${\mathrm{Os}}^{191}$ decays by the emission of beta-rays of maximum energy 1.10 Mev and does not appear to be accompanied by any gamma-rays. ${\mathrm{Os}}^{193}$ decays by beta-particle emission accompanied by two gamma-rays of energy 0.128 and 0.041 Mev. The beta-ray spectrum is obscured by internal conversion and Auger lines. The end point is approximately 0.135 Mev.