Neutron-deficient isotopesGe64andGe65

The ${\beta }^{+}$ decays of ${}_{}{}^{65}{}_{}{}^{}\mathrm{Ge}$ and the new isotope ${}_{}{}^{64}{}_{}{}^{}\mathrm{Ge}$ have been studied by $\gamma$-ray spectrometry with chemically separated sources. Measured half-lives are 30.0 ± 1.2 sec for ${}_{}{}^{65}{}_{}{}^{}\mathrm{Ge}$ and 63.7 ± 2.5 sec for ${}_{}{}^{64}{}_{}{}^{}\mathrm{Ge}$. The decay-scheme studies have been supplemented by investigation of the ${}_{}{}^{64}{}_{}{}^{}\mathrm{Zn}(p,n\gamma ){}_{}{}^{64}{}_{}{}^{}\mathrm{Ga}$ and ${}_{}{}^{64}{}_{}{}^{}\mathrm{Zn}({}_{}{}^3{}_{}{}^{}\mathrm{He},t){}_{}{}^{64}{}_{}{}^{}\mathrm{Ga}$ reactions, and the mass excess of ${}_{}{}^{64}{}_{}{}^{}\mathrm{Ga}$ was found to be -58.819 ± 0.008 MeV. Excitation functions for the (${}_{}{}^3{}_{}{}^{}\mathrm{He},2n$), (${}_{}{}^3{}_{}{}^{}\mathrm{He},3n$) and (${}_{}{}^3{}_{}{}^{}\mathrm{He},p2n$) reactions induced on ${}_{}{}^{64}{}_{}{}^{}\mathrm{Zn}$ are presented for comparison with other work. The question of the role of ${}_{}{}^{64}{}_{}{}^{}\mathrm{Ge}$ in nucleosynthesis is considered.