Decay of 10.2-dayPt188

The decay properties of ${}_{}{}^{188}{}_{}{}^{}\mathrm{Pt}$ were investigated with the use of mass-separated sources. Singles and coincidence measurements were made by using x- and $\gamma$-ray Ge(Li) detectors as well as a Si(Li) electron detector. These results were combined with previously available conversion-electron data which had been obtained with a magnetic spectrometer. From this information a level scheme was constructed for ${}_{}{}^{188}{}_{}{}^{}\mathrm{Ir}$. A tentatively proposed level at 317 keV was eliminated on the basis of our results. In addition, several transitions attributed to ${}_{}{}^{188}{}_{}{}^{}\mathrm{Pt}$ decay were not observed in the present study. $\alpha$ particle and $\gamma$-ray spectra were also measured with the detectors positioned in calibrated geometries. The $\alpha$-decay energy and branching ratio of ${}_{}{}^{188}{}_{}{}^{}\mathrm{Pt}$ were determined to be 3915±10 keV and (2.8±0.5)×${10}^{-7\mathrm{}}$, respectively.