High-spin members of the 4p-4h triaxial band in ⁴⁰Ca

The states of ⁴⁰Ca are described as mixtures of triaxial deformed intrinsic states. The few adjustable parameters are chosen to give good agreement for the low-lying energy levels. It is then found that the model can reproduce the energies of the high-spin states seen in heavy-ion scattering experiments at 9.9 MeV (8⁺) and 12.4 MeV (10⁺). The deviation of the energies of these states from the simple J(J+1)fs pattern can be explained as due to K-band mixing. Additional high-spin states are predicted at 15.8 MeV (12⁺) and 19.6 MeV (14⁺). Electromagnetic transition rates and other observables are generally in good agreement with experimental values.