A radioactive ${}_{}{}^{226}{}_{}{}^{}\mathrm{Ra}$ ($t_{1/2}$=1600 yr) target was used to study the ${}_{}{}^{226}{}_{}{}^{}\mathrm{Ra}$(α,t${)}^{227}$Ac and ${}_{}{}^{226}{}_{}{}^{}\mathrm{Ra}$${(}^3$He,d${)}^{227}$Ac reactions at an incident energy of 30 MeV for both the α and ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ particles. These measurements have confirmed most levels observed in earlier decay-scheme studies, and give evidence for 11 additional levels. Several of the new levels were used in the tentative assignment of two $K^{\pi }$${=(5/2\mathrm{}}^{\pm }$ bands. The experimental data are compared with results from the Nilsson model and a nonadiabatic, rigid, reflection-asymmetric rotor (octupole) model. Although the order and spacing of levels in this mass region can be explained better by models that include an octupole deformation, the spectroscopic strengths in ${}_{}{}^{227}{}_{}{}^{}\mathrm{Ac}$ are in better agreement with those calculated for the reflection-symmetric potential.

• Received 30 October 1987

DOI:https://doi.org/10.1103/PhysRevC.37.1407