Nuclear Levels and Transitions inLu175According to the Unified Model

The scheme for the decay of ${\mathrm{Yb}}^{175}$ and ${\mathrm{Hf}}^{175}$ to ${\mathrm{Lu}}^{175}$ is analyzed theoretically on the basis of the Bohr-Mottelson strong-coupling unified model. A set of spins and parities for all the levels involved is found to be uniquely consistent with the available experimental data and the level-structure predictions of the model. The anomalously large ratio of $M2\mathrm{}$ to $E1\mathrm{}$ radiation observed in two of the gamma transitions is accounted for as a consequence of configuration forbiddenness. Parallel remarks are made concerning the spectrum of ${\mathrm{Hf}}^{177}$.