α decay as a probe for phase transitions in nuclei

A microscopic description of alpha decay to intruder $0_2^{+}$ states in the lead region is presented. The role played by proton-neutron correlations is emphasized. The calculated hindrance factors of transitions to the states $0_2^{+}$ with respect to the corresponding ground state transitions are in good agreement with available experimental data. The abrupt variations in the measured hindrance factors in some cases are related to shape transitions. Predictions for further measurements are given. © 1996 The American Physical Society.