Beyond-mean-field description of octupolarity in dysprosium isotopes with the Gogny-D1M energy density functional

Abstract

The emergence and stability of (static) octupole deformation effects in Dy isotopes from dripline to dripline ($72\le N\le 142$) is analyzed in this paper using mean-field and beyond-mean-field techniques often used for this purpose. We find static octupole deformations at the Hartree-Fock-Bogoliubov (HFB) level with the Gogny D1M force for $N\approx 134$ isotopes, while nuclei with $N\approx 88$ exhibit reflection-symmetric ground states. It is shown that, given the softness found in the mean-field and parity-projected potential energy surfaces along the octupole direction, neither of these two levels of approximation is suficcient to extract conclusions about the (permanent and/or vibrational) nature of octupole dynamic in Dy isotopes. From the analysis of the collective wave functions as well as the excitation energies of the first negative-parity states and $B(E3)$ strengths, obtained within the framework of a two-dimensional symmetry-conserving generator coordinate method (2D-GCM), it is concluded that the increased octupole collectivity in Dy isotopes with $N\approx 88$ and $N\approx 134$ is a vibrational-like effect that is not directly related to permanent mean-field octupole deformation in the considered nuclei. A pronounced suppression of the $B(E1)$ strengths is predicted for isotopes with $N\approx 82$ and $N\approx 126$. The comparison of results obtained with other parametrizations, show the robustness of the predicted trends with respect to the underlying Gogny energy density functional.

13 pages, 7 figures, published in Phys Rev C. arXiv admin note: text overlap with arXiv:2104.08063

References in corpus (18)

• Evolution of Octupole Deformation in Radium Nuclei from Coulomb Excitation of Radioactive ${}^{222}$Ra and ${}^{228}$Ra Beams
• Application of the gradient method to Hartree-Fock-Bogoliubov theory
• Spectroscopy of quadrupole and octupole states in rare-earth nuclei from a Gogny force
• Octupole deformation properties of the Barcelona-Catania-Paris energy density functionals
• Spectroscopy of reflection-asymmetric nuclei with relativistic 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
• Evolution of octupole deformation and collectivity in neutron-rich lanthanides
• Quadrupole-octupole coupling and the onset of octupole deformation in actinides
• Microscopic description of fission in odd-mass uranium and plutonium nuclei with the Gogny energy density functional
• Microscopic description of quadrupole-octupole coupling in neutron-rich actinides and superheavy nuclei with the Gogny-D1M energy density functional
• Quadrupole-octupole coupling and the evolution of collectivity in neutron-deficient Xe, Ba, Ce, and Nd isotopes
• Operator overlaps in harmonic oscillator bases with different oscillator lengths
• Formulation of the Generator Coordinate Method with arbitrary bases
• Spectroscopy of low spin states in 157Dy: Search for evidence of enhanced octupole correlations

Cited by in corpus (6)

• Relativistic Exact Two-Component Coupled-Cluster Study of Molecular Sensitivity Factors for Nuclear Schiff Moments
• Microscopic description of quadrupole-hexadecapole coupling in radium, thorium, uranium and plutonium isotopes with the Gogny energy density functional
• Gallagher-Moszkowski splitting in deformed odd-odd nuclei within a microscopic approach
• Quadrupole-hexadecapole coupling in the rare earth region with beyond mean field correlations
• Interplay of quadrupole and octupole degrees of freedom in the Gd isotopes
• Microscopic description of spontaneous fission based on a Gogny energy density functional including tensor contributions