KandLShakeoff Probability inSm151

We have measured the $K$-electron-emission probability for the 76-keV $\beta$ decay of ${}_{}{}^{151}{}_{}{}^{}\mathrm{Sm}$ and obtain $P_K=(2.4\mathrm{}\pm 0.3)\times {10}^{-6\mathrm{}}$. We correct an earlier measurement to $P_K=(2.3\mathrm{}\pm 0.3)\times {10}^{-6\mathrm{}}$. From the agreement with the Law-Campbell shakeoff-plus-shakeup prediction, 2.2×${10}^{-6\mathrm{}}$, the direct collision contribution to the $K$ emission is limited to $\sim \frac{1}{3}$ of the Feinberg prediction, contrary to recent claims. We obtain an $L$—x-ray probability due to $L$-electron shakeoff per $\beta$ decay of (5.4±1.0) × ${10}^{-4\mathrm{}}$, about half the theoretical value, and also some indication that $L$ shakeoff is predominantly $L_1$.