Nuclear States in the RaEβ-Decay

Abstract

It is shown that the $\beta$-transforming neutron of ${\mathrm{Bi}}^{210}$ most probably has an $i_{\frac{11}{2}}$ character, despite a $g_{\frac{9}{2}}$ character of the ground-state neutron in ${\mathrm{Pb}}^{209}$. This makes a critical difference to the RaE spectrum parameter, $\xi =\frac{i〈\mathrm{r}〉}{〈\sigma \times \mathrm{r}〉}$, yielding $\xi \approx +1\mathrm{}$ rather than $\xi \approx -\frac{1}{10}$. The effect of configuration mixing is also investigated but does not affect $\xi$ appreciably.