Monopole-pairing and deformation in atomic nuclei
The pairing-plus-qua upole model is realized in the framework of the Elliott SU(3) scheme in order to study the complementary and competing features of the pairing and quadrupole-quadrupole interactions. The pairing force is shown to break the SU(3) symmetry and - in conjunction with the quadrupole-quadrupole force - remove almost all degeneracies which occur in the pure symmetry limits of the theory. In addition, ground-state deformations induced by pairing are shown to be triaxial but rather soft, whereas the quadrupole-quadrupole interaction favors prolate or oblate shapes which are sharp. © 1995.