The decays of seniority isomers in the N=82 nuclei ${}_{}{}^{150}{}_{}{}^{}\mathrm{Er}$ and ${}_{}{}^{152}{}_{}{}^{}\mathrm{Yb}$ and in their respective N=81 isotopes ${}_{}{}^{149}{}_{}{}^{}\mathrm{Er}$ and ${}_{}{}^{151}{}_{}{}^{}\mathrm{Yb}$ were studied following mass separation by the Argonne Fragment Mass Analyzer. Conversion electrons were detected with Si p-i-n diodes operated at room temperature. The low-energy isomeric transitions in ${}_{}{}^{151,152}{}_{}{}^{}\mathrm{Yb}$ have been observed for the first time in the electron spectra. Multipolarity assignments were made for many of the decay γ rays of the four nuclei.

• Received 25 April 1995

DOI:https://doi.org/10.1103/PhysRevC.52.1355