A superallowed Fermi $\beta$ transition ($J^{\pi }=0^{+}, T=1\mathrm{}$) from ${}_{}{}^{42}{}_{}{}^{}\mathrm{Ga} \mathrm{}(A=4n+2\mathrm{})\mathrm{}$ has been identified. The measured half-life and $\beta$ ray end point energy are $T_{\frac{1}{2}}=116.4\mathrm{}\pm 1.5$ msec and $E_{\beta max}=8.3\mathrm{}\pm 0.3$ MeV, respectively. The $\mathrm{Ft}$ value for the transition has been evaluated with the measured half-life and estimated $\beta$ ray end point energy from a phenomenological analysis of the Coulomb displacement energies of isobaric analog states. The obtained value is $Ft=ft(1+{\delta }_R)(1-{\delta }_C)=3103\mathrm{}\pm 44$ sec which turns out to be 0.6% larger than that expected for such $0^{+}$-$0^{+}$ superallowed β transitions.

RADIOACTIVITY ${}_{}{}^{62}{}_{}{}^{}\mathrm{Ga}$ [from ${}_{}{}^{64}{}_{}{}^{}\mathrm{Zn}(p,3n)$]; measured $T_{\frac{1}{2}}$ $E_{\beta max}$; deduced $\Delta E_C$, $\mathcal{F}t$ value.

• Received 13 January 1978

DOI:https://doi.org/10.1103/PhysRevC.17.2219