Evolution of octupole deformation and collectivity in neutron-rich lanthanides

Abstract

The onset of octupole deformation and its impact on related spectroscopic properties is studied in even-even neutron-rich lanthanide isotopes Xe, Ba, Ce, and Nd with neutron number $86⩽N⩽94$. Microscopic input comes from the Hartree-Fock-Bogoliubov approximation with constrains on the axially symmetric quadrupole and octupole operators using the Gogny-D1M interaction. At the mean-field level, reflection asymmetric ground states are predicted for isotopes with neutron number around $N=88$. Spectroscopic properties are studied by diagonalizing the interacting boson model Hamiltonian, with the parameters obtained via the mapping of the mean-field potential energy surface onto the expectation value of the Hamiltonian in the $s$, $d$, and $f$ boson condensate state. The results obtained for low-energy positive- and negative-parity excitation spectra as well as the electric dipole, quadrupole, and octupole transition probabilities indicate the onset of pronounced octupolarity for $Z\approx 56$ and $N\approx 88$ nuclei.

15 pages, 13 figures, 2 tables

References in corpus (14)

• Relativistic Nuclear Energy Density Functionals: adjusting parameters to binding energies
• Evolution of Octupole Deformation in Radium Nuclei from Coulomb Excitation of Radioactive ${}^{222}$Ra and ${}^{228}$Ra Beams
• Microscopic Formulation of Interacting Boson Model for Rotational Nuclei
• Spectroscopy of quadrupole and octupole states in rare-earth nuclei from a Gogny force
• Spectroscopy of reflection-asymmetric nuclei with relativistic energy density functionals
• Octupole deformation properties of the Barcelona-Catania-Paris energy density functionals
• Octupole deformation in the nuclear chart based on the 3D Skyrme Hartree-Fock plus BCS model
• Octupole deformation in the ground states of even-even $Z\sim 96,N\sim 196$ actinides and superheavy nuclei
• Octupole deformation properties of actinide isotopes within a mean field approach
• Ground state octupole correlation energies with effective forces
• Microscopic description of fission in superheavy nuclei with the parametrization D1M${}^{\ast }$ of the Gogny energy density functional
• Quadrupole-octupole coupling and the onset of octupole deformation in actinides
• Microscopic description of quadrupole-octupole coupling in neutron-rich actinides and superheavy nuclei with the Gogny-D1M energy density functional
• Coupling of pairing and triaxial shape vibrations in collective states of $\gamma$-soft nuclei

Cited by in corpus (2)

• Octupole correlations in collective excitations of neutron-rich $N\approx 56$ nuclei
• Simultaneous description of $\beta$ decay and low-lying structure of neutron-rich even- and odd-mass Rh and Pd nuclei