Parity shift and beat staggering structure of octupole bands in a collective model for quadrupole-octupole deformed nuclei

Abstract

We propose a collective model formalism which describes the strong parity shift observed in low-lying spectra of nuclei with octupole deformations together with the fine rotational band structure developed at higher angular momenta. The parity effect is obtained by the Schroedinger equation for oscillations of the reflection asymmetric (octupole) shape between two opposite orientations in an angular momentum dependent double-well potential. The rotational structure is obtained by a collective quadrupole-octupole rotation Hamiltonian. The model scheme reproduces the complicated beat staggering patterns observed in the octupole bands of light actinide nuclei. It explains the angular momentum evolution of octupole spectra as the interplay between the octupole shape oscillation (parity shift) mode and the stable quadrupole-octupole rotation mode.

arXiv comment16 pages, 7 figures

References in corpus (4)

• Cluster Interpretation of Properties of Alternating Parity Bands in Heavy Nuclei
• Analytic Description of Critical Point Actinides in a Transition from Octupole Deformation to Octupole Vibrations
• Description of nuclear octupole and quadrupole deformation close to the axial symmetry and phase transitions in the octupole mode
• "Beat" patterns for the odd-even staggering in octupole bands from a quadrupole-octupole Hamiltonian

Cited by in corpus (7)

• Nuclear collective motion with a coherent coupling interaction between quadrupole and octupole modes
• Octupole deformation in the nuclear chart based on the 3D Skyrme Hartree-Fock plus BCS model
• Non-yrast nuclear spectra in a model of coherent quadrupole-octupole motion
• Application of the triaxial quadrupole-octupole rotor to the ground and negative-parity levels of actinide nuclei
• Electromagnetic Transition Strengths in Heavy Nuclei
• Axially Symmetric Quadrupole-Octupole Model incorporating Sextic Potential
• Probing alternating-parity bands in even-even nuclei within an axial quadrupole-octupole-hexadecapole collective model