The β decay of the neutron-rich nuclei ${}^{51-53}\mathrm{K}$ has been used to populate bound and unbound states in ${}^{50-53}\mathrm{Ca}$. Measurements of γ rays as well as β-delayed neutrons enabled detailed decay schemes to be established and levels identified in ${}^{50-53}$Ca. A delayed one-neutron emission probability $P_{1n}$ of $63\pm 8$% was determined for the decay of ${}^{51}\mathrm{K}$. A total of seven new γ transitions were observed following the decay of ${}^{51}\mathrm{K}$, and 25 neutron branches were found that enrich the level scheme of ${}^{51}\mathrm{Ca}$. Delayed neutron emission probabilities of $P_{1n}=74.4\pm 9.3$% and $P_{2n}=2.3\pm 0.3$% were determined for the decay of ${}^{52}\mathrm{K}$, and 12 new γ transitions were observed in ${}^{50,51,52}\mathrm{Ca}$. Three new γ transitions were observed in ${}^{52,53}\mathrm{Ca}$ following the β decay of ${}^{53}\mathrm{K}$. New limits on the $P_{1n}$ and $P_{2n}$ values were determined for the β decay of ${}^{53}\mathrm{K}$, and a decay scheme was established for ${}^{53}\mathrm{Ca}$ for the first time. The data obtained here should help clarify the structure of neutron-rich $\mathit{fp}$-shell nuclei around the $N=32\text{−}34$ subshell closures.

• Received 25 April 2005

DOI:https://doi.org/10.1103/PhysRevC.74.014313