Electromagnetic Properties of theIπ= 11/2−isomers in the cadmium isotopes: What can we learn from them?

The electromagnetic features of the 11/2− isomers in the odd-mass Cd isotopes are shown to exhibit an an anomaly near N = 70. We report shell-model calculations of these isotopes aimed at describing these properties. We find a sudden phase change in the hexadecapole component of the wave functions precisely at N = 70, which gives rise to different linear relations between the Q and μ values before and after N = 70, as needed to reproduce the experimental data. The particle-hole transformation properties associated with a strong subshell closure at N = 70 followed by fairly close-lying neutron orbitals from N = 70 − 82 is suggested as a possible explanation for this phase change.