Dynamic Penetration Effects in the Internal Conversion of Electric Dipole Transitions inLu175

Abstract

Internal-conversion coefficients are reported for the 396.3-, 282.5-, and 144.8-keV electric dipole transitions in ${\mathrm{Lu}}^{175}$; these occur between the 396.3-keV $\frac{9}{2}-$ state of the [$514\uparrow$] band and the $\frac{7}{2}+$, $\frac{9}{2}+$, and $\frac{11}{2}+$ members of the ground-state [$404\downarrow$] band. Values for $K$ and $L_1$ shells were determined directly, and for the $L_2$ and $L_3$ shells the coefficients were obtained from the $L_1$ and $K$ values and the $L_1:L_2:L_3$ ratio measurements of Herrlander and Ewan. The dynamic penetration terms, $\mathbf{j}·\mathbf{\nabla }$ and $\mathbf{j}·\mathbf{r}$, and the $M2\mathrm{}$ admixtures were determined. For the 282.5-keV transition, additional information from Thun et al. on the electron-gamma angular correlation was used in the analysis. The amounts of $M2\mathrm{}$ admixture were found to be small, the $\mathbf{j}·\mathbf{\nabla }$ nuclear matrix elements are consistent with zero, and the $\mathbf{j}·\mathbf{r}$ matrix elements are in good agreement with rotational-model predictions.