Semiclassical description of exotic nuclear shapes

Exotic nuclear structures such as bubbles and tori are analyzed through semiclassical extended Thomas-Fermi calculations with the Skyrme force SkM*. The variational equations for neutron and proton densities are solved fully self-consistently in spherical (bubbles) and cylindrical (tori) symmetries. The possible existence of bubble configurations in some astrophysical scenarios is discussed. The stability of toroidal structures against change of quadrupole moment is studied. A global minimum of the energy is found in heavy toroidal nuclei.