1202.5631 (Ken-ichiro Arita)

Periodic-orbit approach to the nuclear shell structures with power-law
potential models I: Bridge orbits and prolate-oblate asymmetry    [PDF]

Ken-ichiro Arita

Deformed shell structures in nuclear mean-field potentials are systematically investigated as functions of deformation and surface diffuseness. As the mean field model to investigate nuclear shell structures in wide range of mass numbers, we propose the radial power-low potential model, V \propto r^\alpha, which enables us a simple semiclassical analysis by the use of its scaling property. We find remarkable shell structures emerge at certain combinations of deformation and diffuseness parameters, and they are closely related to the periodic orbit bifurcations. In particular, significant roles of the "bridge orbit bifurcations" for normal and superdeformed shell structures are pointed out. It is shown that the prolate-oblate asymmetry in deformed shell structures is clearly understood from the contribution of bridge orbit to the semiclassical level density. The roles of bridge orbit bifurcations to the emergence of superdeformed shell structures are also discussed.

View original: http://arxiv.org/abs/1202.5631