βdecay studies of the neutron-rich56–58Visotopes

$\beta$ decay of ${}^{56,57,58}\mathrm{V}$ has been used to populate low-energy levels of ${}^{56,57,58}\mathrm{Cr},$ respectively. The low-energy levels of the even-even Cr isotopes and $\beta$-decay half-lives and branching ratios of the parent V isotopes are compared to results of shell-model calculations. The Cr energy level calculations were completed in the full $\mathrm{pf}$-model space, using several different interactions. The systematic variation of ${E(2\mathrm{}}_1^{+}),$ which is indicative of a subshell closure at $N=32,$ was best reproduced in calculations using a pf-shell-model interaction based on effective two-body matrix elements with some replacement by the G matrix.