Lifetime and branching ratio of the second excited state ofK38

The lifetime of the second excited state of ${}_{}{}^{38}{}_{}{}^{}\mathrm{K}$ has been determined to be 12 ± 2 ps using a recoil-distance technique with the reaction ${}_{}{}^{24}{}_{}{}^{}\mathrm{Mg}({}_{}{}^{16}{}_{}{}^{}\mathrm{O}, pn)$. The $\frac{E2\mathrm{}}{M1\mathrm{}}$ branching ratio was found to be (0.96 ± 0.10)% using the reaction ${}_{}{}^{35}{}_{}{}^{}\mathrm{Cl}(\alpha , n)$ just above threshold. The excitation energies of the first two excited states have been found to be 130.2 ± 0.4 and 458.7 ± 0.3 keV. These results are compared with prior experimental and theoretical work.