βdecay and isomeric properties of neutron-rich Ca and Sc isotopes

Abstract

The isomeric and $\ensuremath{\beta}$-decay properties of neutron-rich $^{53\ensuremath{-}57}\mathrm{Sc}$ and $^{53,54}\mathrm{Ca}$ nuclei near neutron number $N=32$ are reported, and the low-energy level schemes of $^{53,54,56}\mathrm{Sc}$ and $^{53\ensuremath{-}57}\mathrm{Ti}$ are presented. The low-energy level structures of the ${}_{21}\mathrm{Sc}$ isotopes are discussed in terms of the coupling of the valence $1{f}_{7/2}$ proton to states in the corresponding ${}_{20}\mathrm{Ca}$ cores. Implications with respect to the robustness of the $N=32$ subshell closure are discussed, as well as the repercussions for a possible $N=34$ subshell closure.