A new neutron-rich isotope, ${}_{}{}^{196}{}_{}{}^{}\mathrm{Os}$, was identified as the product of the ${}_{}{}^{198}{}_{}{}^{}\mathrm{Pt}\mathrm{}(n,2\mathrm{pn})\mathrm{}$ reaction. Chemically separated sources were used to characterize its $\beta$ and $\gamma$ radiations. The new isotope decays with a half-life of 34.9 ± 0.2 min. Ten $\gamma$ rays have been assigned to this decay, the strongest being at 407.9 keV. A $Q_{{\beta }^{-}}$ of 0.84 MeV was inferred from $\beta -\gamma$ coincidence measurements. $\gamma$-ray energies and intensities as well as $Q_{{\beta }^{-}}$ for the decay of the 52-sec ${}_{}{}^{196}{}_{}{}^{}\mathrm{Ir}$ daughter of ${}_{}{}^{196}{}_{}{}^{}\mathrm{Os}$ have been remeasured and are in agreement with the results of an earlier investigation. A partial decay scheme for ${}_{}{}^{196}{}_{}{}^{}\mathrm{Os}$ is proposed.

RADIOACTIVITY ${}_{}{}^{196}{}_{}{}^{}\mathrm{Os}$ [from ${}_{}{}^{198}{}_{}{}^{}\mathrm{Pt}\mathrm{}(n,2\mathrm{pn})\mathrm{}$, medium energy neutron beam]; measured $T_{\frac{1}{2}}$; $E_{\gamma }$, $I_{\gamma }$, $E_{\beta }$, $\beta \gamma$ coin; deduced $log\mathrm{ft}$ limits. ${}_{}{}^{196}{}_{}{}^{}\mathrm{Ir}$ measured $E_{\gamma }$, $I_{\gamma }$, $E_{\beta }$; deduced levels, $J$, $\pi$. Enriched targets, radiochemistry, Ge(Li), Si(Li), and plastic detectors.

• Received 6 June 1977

DOI:https://doi.org/10.1103/PhysRevC.16.1559