SHAPE EVOLUTION FOR Ce ISOTOPES IN RELATIVISTIC MEAN-FIELD THEORY

The evolution of shape from the axially deformed to the spherical shapes in the Ce isotopes is investigated microscopically in relativistic mean-field theory. The microscopic and self-consistent quadruple deformation constrained relativistic mean-field calculations show a clear change for the even-even Ce isotopes with N = 62 ~ 84. The potential surfaces for 128 Ce , 130 Ce , 132 Ce and 134 Ce are found to be relatively flat, which may be the possible critical-point nuclei. Similar conclusions can also be drawn from the microscopic single-particle spectra.