Systematic study of rigid triaxiality in Ba–Pt nuclei and role of $$Z=64$$ Z = 64 subshell effect

Abstract

A systematic variation of shape variables $$\beta $$ and $$\gamma $$ with N and $$N_\mathrm {p}N_\mathrm {n}$$ is studied in the framework of an asymmetric rotor model of Davydov and Filippov for the $$Z=$$ 50–82, $$N=$$ 82–126 major shell space. The role of the $$Z=64$$ subshell in producing smooth systematics has been discussed. The quadrupole moments are extracted after considering both axially symmetric and axially asymmetric nuclei. The correlation of $$\beta $$ with $$\gamma $$ together with the measured quadrupole moments indicates that $$\gamma $$ -rigidity is better observed in nuclei with modest deformation.