Shape evolution and coexistence in neutron-rich Yb, Hf, W, Os, and Pt nuclei

We have investigated the shape evolution and shape coexistence in the even-even neutron-rich isotopes of Yb, Hf, W, Os, and Pt and the isotones N = ۱۱۰-۱۲۲ in the A~۱۹۰ within the microscopic-macroscopic Cranked Nilsson-Strutinsky framework. Here, we have focused on the potential energy surface (PES) calculations to detect shape variations with N and Z. The PESs in the ground state for low-lying energy show the presence of collective and non-collective bands. The results are comparable to the studies of others where the pairing correlation was also included. It is evident deformation changes in the isotopic and isotonic chains with increasing the neutron and proton number and the filling of closed shells. The qualitative consistency of our calculations without pairing correlations, especially on the position of the PES's minima, shows that the pairing force has no a considerable effect on the nuclear shape at least in the mass region A~۱۹۰.

Keywords:

Cranked Nilsson-Strutinsky method , PES calculations , deformation parameters , shape coexistence , shape evolution