Nuclear collective motion with a coherent coupling interaction between quadrupole and octupole modes

Abstract

A collective Hamiltonian for the rotation-vibration motion of nuclei is considered, in which the axial quadrupole and octupole degrees of freedom are coupled through the centrifugal interaction. The potential of the system depends on the two deformation variables ${\beta }_2$ and ${\beta }_3$. The system is considered to oscillate between positive and negative ${\beta }_3$-values, by rounding an infinite potential core in the $({\beta }_2,{\beta }_3)$-plane with ${\beta }_2>0$. By assuming a coherent contribution of the quadrupole and octupole oscillation modes in the collective motion, the energy spectrum is derived in an explicit analytic form, providing specific parity shift effects. On this basis several possible ways in the evolution of quadrupole-octupole collectivity are outlined. A particular application of the model to the energy levels and electric transition probabilities in alternating parity spectra of the nuclei ${}^{150}$Nd, ${}^{152}$Sm, ${}^{154}$Gd and ${}^{156}$Dy is presented.

25 pages, 13 figures. Accepted in Phys. Rev. C

References in corpus (4)

• Effects of beta-gamma coupling in transitional nuclei and the validity of the approximate separation of variables
• 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
• Parity shift and beat staggering structure of octupole bands in a collective model for quadrupole-octupole deformed nuclei

Cited by in corpus (15)

• Reduced transition probabilities for the gamma decay of the 7.8 eV isomer in ${}^{229}$Th
• Microscopic description of quadrupole-octupole coupling in Sm and Gd isotopes with the Gogny Energy Density Functional
• Non-yrast nuclear spectra in a model of coherent quadrupole-octupole motion
• Description of nuclear octupole and quadrupole deformation close to the axial symmetry: Critical-point behavior of 224Ra and 224Th
• Octupole degree of freedom for the critical-point candidate nucleus ${}^{152}$Sm in a reflection-asymmetric relativistic mean-field approach
• Theoretical predictions for the magnetic dipole moment of ${}^{229m}$Th
• Octupole correlations in low-lying states of 150Nd and 150Sm and their impact on neutrinoless double-beta decay
• Description of nuclear octupole and quadrupole deformation close to the axial symmetry: Octupole vibrations in the X(5) nuclei 150Nd and 152Sm
• ${}^{229m}$Th isomer from a nuclear model perspective
• The electric quadrupole channel of the 7.8 eV ${}^{229}\mathrm{Th}$ transition
• Microscopic description of quadrupole-octupole coupling in actinides with the Gogny-D1M energy density functional
• Nuclear coherent population transfer to the ${}^{229m}$Th isomer using x-ray pulses
• Investigation of octupole vibrational states in 150Nd via inelastic proton scattering (p,p'g)
• Non-yrast spectra of odd-A nuclei 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