The ${\beta }^{+}$ decay of the new isotope ${}_{}{}^{67}{}_{}{}^{}\mathrm{As}$ to levels in ${}_{}{}^{67}{}_{}{}^{}\mathrm{Ge}$ has been studied via the reaction ${}_{}{}^{58}{}_{}{}^{}\mathrm{Ni}({}_{}{}^{14}{}_{}{}^{}\mathrm{N}, \alpha n){}_{}{}^{67}{}_{}{}^{}\mathrm{As}_{\to }^{\beta +67\mathrm{}}{}_{}{}^{}\mathrm{Ge}$ using 39- and 41-MeV ${}_{}{}^{14}{}_{}{}^{}\mathrm{N}$ ions. The ${}_{}{}^{67}{}_{}{}^{}\mathrm{As}$ half-life and total decay energy ($Q_{\mathrm{EC}}$) have been measured to be 42.5 ± 1.2 s and 6.01 ± 0.10 MeV, respectively. The ${\beta }^{+}$ decay scheme to 15 levels up to 2524-keV excitation in ${}_{}{}^{67}{}_{}{}^{}\mathrm{Ge}$ has been determined and, based on measured $log\mathrm{ft}$ values, a spin/parity constraint of $\frac{3}{2^{-}}$ or $\frac{5}{2^{-}}$ for the ground state of ${}_{}{}^{67}{}_{}{}^{}\mathrm{As}$ has been established.

RADIOACTIVITY ${}_{}{}^{67}{}_{}{}^{}\mathrm{As}$ [from ${}_{}{}^{58}{}_{}{}^{}\mathrm{Ni}({}_{}{}^{14}{}_{}{}^{}\mathrm{N}, \alpha n)$]: measured $T_{\frac{1}{2}}$, $E_{\gamma }$, $I_{\gamma }$, $\gamma -\gamma$ coin, $E_{{\beta }^{+}}$, ${\beta }^{+}-\gamma$ coin; deduced decay scheme, mass excess, $log\mathrm{ft}$ values, $J^{\pi }$ restrictions; ${}_{}{}^{67}{}_{}{}^{}\mathrm{Ge}$ $J^{\pi }$ restrictions. Enriched targets, multiple rabbit, helium jet, Ge(Li) and plastic detectors.

• Received 27 March 1980

DOI:https://doi.org/10.1103/PhysRevC.22.2204