Prediction and possible observation of an oblate shape isomer in 190W

Energy-surface calculations for nuclides in the neutron-rich 19074W116 region show consistently that the collective rotation of a deformed oblate shape is an energetically favoured mode, especially for angular momenta I>12ℏ. By comparing the calculations with existing experimental data, it is concluded that the reported t1/2∼1 ms isomer in 190W may be an oblate shape isomer.