Mixing Ratios of Transitions in the Decay ofIr192

Mixing ratios of the 485-keV transition in ${\mathrm{Os}}^{192}$ and the 296-, 308-, and 604-keV transitions in ${\mathrm{Pt}}^{192}$ populated from the decay of ${\mathrm{Ir}}^{192}$ were measured using the $\gamma -\gamma$ directional-correlation method. In addition, the 468-316-keV, 589-612-keV, 885-316-keV, and 1063-316-keV $\gamma -\gamma$ directional correlations in ${\mathrm{Pt}}^{192}$ have been remeasured. Coaxial and planar Ge(Li) detectors and NaI(Tl) scintillation detectors were used in different combinations depending on the energy resolution required for a particular measurement. The results for the mixing ratios are ${\delta }_{485}=+\left({{10.9}_{-1.5\mathrm{}}}^{+2.1\mathrm{}}\right)$, ${\delta }_{296}=-\left({{9.1}_{-1.7\mathrm{}}}^{+2.7\mathrm{}}\right)$, ${\delta }_{308}=-(9.9\mathrm{}\pm 1.0)$, and ${\delta }_{604}=+(2.0\mathrm{}\pm 0.2)$. The over-all agreement of the signs, as well as the absolute values of the mixing ratios with predictions of the pairing-plus-quadrupole model of Kumar and Baranger, is good.