Isomer bands, E0 transitions, and mixing due to shape coexistence in ₈₂¹⁸⁸Pb₁₀₆

Structures above the two-particle isomeric states in ¹⁸⁸Pb have been identified. Their properties imply the presence of three minima in the nuclear potential well, associated with spherical, oblate, and prolate deformations. The fragmented decay of the K^π = 8^-, 1 μs prolate isomer leads to the identification of the yrare collective band presumably based on the excited 0⁺ state. Analysis of the excitation energies, branching ratios, and E2 and E0 decay widths through a three-band-mixing model provides evidence for shape differences and the hybridization of the wave functions at low spin.