Beta-Gamma Directional Correlations in the DecaySb124→Te124

We have measured the $\beta -\gamma$ directional correlations involving the 1.6-Mev $\beta$ group of ${\mathrm{Sb}}^{124}$ and the second excited $2^{+}$ state (at 1325 kev) of ${\mathrm{Te}}^{124}$. Both of the $\gamma$ rays (0.72 and 1.32 Mev) de-exciting this state were used. For the 0.72-Mev $\gamma$ ray, the results for the coefficient $\epsilon$ in $W\left(\theta \right)=1+\epsilon P_2\left(cos\theta \right)$ are: $\epsilon =0.20\mathrm{}\pm 0.02, 0.18\pm 0.02, 0.19\pm 0.03, \mathrm{and} 0.22\pm 0.06$ for $\beta$ energies of 1.02, 1.16, 1.30, and 1.44±0.07 Mev, respectively. For the 1.32-Mev $\gamma$ ray, we find $\epsilon =-0.28\mathrm{}\pm 0.08$ for a $\beta$-energy range of 1.0-1.6 Mev. From these results, the mixing ratio for the 0.72-Mev $\gamma$ ray is $\delta ={{+0.8\mathrm{}}_{-0.2\mathrm{}}}^{+0.7\mathrm{}}$. It is shown that the 1.6-Mev $\beta$ transition must be due, at least partly, to the $B_{\mathrm{ij}}$ matrix element. By assuming $u=x=0\mathrm{}$ (in Kotani's notation), our data can be fitted by either $\frac{Y}{z}=0.04\mathrm{}$ (i.e., an essentially unique transition), or $\frac{Y}{z}=1.2\mathrm{}$. Evidence for the existence of a 1.25-Mev level in ${\mathrm{Te}}^{124}$ is also given.