The nuclide ${}_{}{}^{45}{}_{}{}^{}\mathrm{K}$ has been produced by fragmentation of a uranium carbide target with 600 MeV protons and also, as a daughter product of the disintegration of ${}_{}{}^{45}{}_{}{}^{}\mathrm{Ar}$, by the $\mathrm{V}(p, 6pxn)\mathrm{Ar}$ spallation reaction on a vanadium carbide target. Its $\beta$ decay to ${}_{}{}^{45}{}_{}{}^{}\mathrm{Ca}$ has been studied via delayed $\gamma$-ray singles and coincidence techniques. Evidence is found for approximately 10 new $\beta$ branches. Excitation energies in ${}_{}{}^{45}{}_{}{}^{}\mathrm{Ca}$ and $\gamma$-branching fractions have been determined for 16 levels. Spectroscopic data deduced from the $\beta$ decay selection rules are compared to theoretical predictions.

RADIOACTIVITY ${}_{}{}^{45}{}_{}{}^{}\mathrm{K}$ from $p+U$ at 600 MeV and from $\mathrm{V}(p, 6pxn){}_{}{}^{45}{}_{}{}^{}\mathrm{Ar}\left({\beta }^{-}\right)$, natural targets, mass separated, measured delayed $E_{\gamma }$, $I_{\gamma }$, $\gamma -\gamma$ coincidences, $T_{\frac{1}{2}}$, deduced decay scheme, $log\mathrm{ft}$, $J$, $\pi$.

• Received 29 April 1980

DOI:https://doi.org/10.1103/PhysRevC.22.1245