Microscopic analysis of the ground state properties of the even-even Dy isotopes in the reflection-asymmetric relativistic mean-field theory

Abstract

Reflection-asymmetric relativistic mean-field theory is used to explore the ground state properties for the even-even Dy isotopes. The results are compared with those from the finite-range droplet model (FRDM), the deformed relativistic Hartree-Bogoliubov theory in continuum (DRHBc), and the available data. The calculated binding energies and quadrupole deformations agree with the experimental data as well as the FRDM and DRHBc calculations. The obtained matter density distributions and potential energy surfaces clearly exhibit the ground state shapes and the presence of deformation in these nuclei. The experimental fingerprints of octupolarity in $^{148,154,156,160}\mathrm{Dy}$ around $N=88$ are convincing in the present calculations. The predictions on the octupole deformation in $^{190\text{--}194,200,202}\mathrm{Dy}$ around $N=134$ agree with the results from the FRDM calculations. In addition, we obtain more knowledge about the shape evolution and phase transition from oblate to pear shape and then to prolate shapes in the Dy isotopes.