Spins and lifetimes of yrast states inCa40

The yrast cascade in ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$ has been studied using the ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}({}_{}{}^{14}{}_{}{}^{}\mathrm{N},pn){}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$ reaction at 36 MeV bombarding energy. The mean lives of two previously reported states at 6931 and 8099 keV excitation have been measured and found to be ${0.49}_{-0.25\mathrm{}}^{+0.13\mathrm{}}$ and 18.1 ± 2.5 ps, respectively. Angular correlation experiments have been performed to confirm the spin-parity assignments of $6^{+}$ and $8^{+}$, respectively. On the basis of the present lifetime measurements, the $6^{+}$ state is believed to belong to the 4p-4h deformed band, but the structure of the $8^{+}$ state is uncertain. No evidence is found for a ${10}^{+}$ level below 11 MeV.