The $K$- and $L$-subshell internal-conversion coefficients of the anomalous 150.4-keV transition in ${}_{}{}^{177}{}_{}{}^{}\mathrm{Lu}$ have been measured with a double-focusing electron spectrometer and a Ge(Li) $\gamma$-ray spectrometer. The analysis of the results gave the $M2\mathrm{}$ content, $Q=(0.92\mathrm{}\pm 0.88)\%$, and the penetration parameters, ${\lambda }_1=-21.4\mathrm{}\pm 2.3$, and ${\lambda }_2=-660\mathrm{}\pm 900$. Using these results along with the known lifetime of the 150.4-keV level, the $E1\mathrm{}$ and $M2\mathrm{}$ $\gamma$-ray matrix elements and the $\int {\overrightarrow{\mathrm{J}}}_n·\overrightarrow{\mathrm{r}}$ and the $\int {\overrightarrow{\mathrm{J}}}_n·\overrightarrow{\nabla }$ type penetration matrix elements were evaluated and compared with those of similar transitions in ${}_{}{}^{175}{}_{}{}^{}\mathrm{Lu}$ and ${}_{}{}^{181}{}_{}{}^{}\mathrm{Ta}$ and with the estimates of the Nilsson model.

• Received 24 April 1972

DOI:https://doi.org/10.1103/PhysRevC.6.1394