Geometrical model description of shape coexistence in Se isotopes

The coexistence and mixing between near-spherical and well-deformed shapes in ^72,74,76Se nuclei is studied with a phenomenological exactly separable Bohr model employing a potential with two competing minima in the axial deformation. The dynamical evolution of the nuclear shapes and the emergence of shape mixing effects is investigated for the collective low-lying states by means of the corresponding effective potentials and the deformation probability distribution. The experimental energy levels and the electromagnetic properties of the considered nuclei are found to be in agreement with the proposed behavior of the shape dynamics.