High-spin torus isomers and their precession motions

Abstract

We systematically investigate the existence of exotic torus isomers and their precession motions for a series of $N=Z$ even-even nuclei from ${}^{28}$Si to ${}^{56}$Ni. We analyze the microscopic shell structure of the torus isomer and discuss why the torus shape is generated beyond the limit of large oblate deformation. We use the cranked three-dimensional Hartree-Fock (HF) method with various Skyrme interactions in a systematic search for high-spin torus isomers. We use the three-dimensional time-dependent Hartree-Fock (TDHF) method for describing the precession motion of the torus isomer. We obtain high-spin torus isomers in ${}^{36}$Ar, ${}^{40}$Ca, ${}^{44}$Ti, ${}^{48}$Cr, and ${}^{52}$Fe. The emergence of the torus isomers is associated with the alignments of single-particle angular momenta, which is the same mechanism as found in ${}^{40}$Ca. It is found that all the obtained torus isomers execute the precession motion at least two rotational periods. The moment of inertia about a perpendicular axis, which characterizes the precession motion, is found to be close to the classical rigid-body value. The high-spin torus isomer of ${}^{40}$Ca is not an exceptional case. Similar torus isomers exist widely in nuclei from ${}^{36}$Ar to ${}^{52}$Fe and they execute the precession motion. The torus shape is generated beyond the limit of large oblate deformation by eliminating the $0s$ components from all the deformed single-particle wave functions to maximize their mutual overlaps.

References in corpus (7)

• The Skyrme Interaction in finite nuclei and nuclear matter
• The TDHF Code Sky3D
• Existence of exotic torus configuration in high-spin excited states of ${}^{40}$Ca
• High-K Precession modes: Axially symmetric limit of wobbling motion
• Gross shell structure at high spin in heavy nuclei
• Spin-isospin Response in Finite Nuclei from an Extended Skyrme Interaction
• Pure Collective Precession Motion of High-Spin Torus Isomer

Cited by in corpus (12)

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• TDHF Theory and Its Extensions for the Multinucleon Transfer Reaction: a Mini Review
• Hyperheavy nuclei: existence and stability
• Extension of nuclear landscape to hyperheavy nuclei
• Evidence for high excitation energy resonances in the 7 alpha disassembly of ${}^{28}$Si
• Toroidal high-spin isomers in the nucleus ${}^{304}120$
• Toroidal states in ${}^{28}$Si with covariant density functional theory in 3D lattice space
• Quantal rotation and its coupling to intrinsic motion in nuclei
• Hyperheavy spherical and toroidal nuclei: the role of shell structure
• Toroidal high-spin isomers in light nuclei with N not equal to Z
• Spin Quantization in Heavy Ion Collision
• Shells in a Toroidal Nucleus in the Intermediate Mass Region