Quantal rotation and its coupling to intrinsic motion in nuclei

Abstract

Symmetry breaking is an importance concept in nuclear physics and other fields of physics. Self-consistent coupling between the mean-field potential and the single-particle motion is a key ingredient in the unified model of Bohr and Mottelson, which could lead to a deformed nucleus as a consequence of spontaneous breaking of the rotational symmetry. Some remarks on the finite-size quantum effects are given. In finite nuclei, the deformation inevitably introduces the rotation as a symmetry-restoring collective motion (Anderson-Nambu-Goldstone mode), and the rotation affects the intrinsic motion. In order to investigate the interplay between the rotational and intrinsic motions in a variety of collective phenomena, we use the cranking prescription together with the quasiparticle random phase approximation. At low spin, the coupling effect can be seen in the generalized intensity relation. A feasible quantization of the cranking model is presented, which provides a microscopic approach to the higher-order intensity relation. At high spin, the semiclassical cranking prescription works well. We discuss properties of collective vibrational motions under rapid rotation and/or large deformation. The superdeformed shell structure plays a key role in emergence of a new soft mode which could lead to instability toward the $K^{\pi }=1^{-}$ octupole shape. A wobbling mode of excitation, which is a clear signature of the triviality, is discussed in terms of a microscopic point of view. A crucial role played by the quasiparticle alignment is presented.

38 pages, 11 figures, Contribution to the Focus issue to celebrate the 40 year anniversary of the 1975 Nobel Prize

References in corpus (8)

• Amplitude / Higgs Modes in Condensed Matter Physics
• Microscopic description of oblate-prolate shape mixing in proton-rich Se isotopes
• A further look at prolate dominance in nuclear deformation
• Microscopic calculation of the wobbling excitations by using the Woods-Saxon potential as a nuclear mean-field
• Parametrizations of triaxial deformation and E2 transitions of the wobbling band
• High-spin torus isomers and their precession motions
• Microscopic Description of Nuclear Wobbling Motion -- Rotation of traxially deformed nuclei --
• Single-phonon and multi-phonon excitations of the $\gamma$ vibration in rotating odd-$A$ nuclei

Cited by in corpus (7)

• Beyond the Unified Model
• Two quasiparticle wobbling in the even-even nucleus 130Ba
• Rotational motion of triaxially deformed nuclei studied by microscopic angular-momentum-projection method II: Chiral doublet band
• Rotational motion of triaxially deformed nuclei studied by microscopic angular-momentum-projection method I: Nuclear wobbling motion
• Influence of moments of inertia on transverse wobbling mode in odd-mass nuclei
• Influence of triaxial deformation on wobbling motion in even-even nuclei
• Collective inertial masses in nuclear reactions