English

Pure Collective Precession Motion of High-Spin Torus Isomer

Nuclear Theory 2015-06-17 v1

Abstract

We investigate the precession motion of the exotic torus configuration in high-spin excited states of 40^{40}Ca. For this aim, we use the three-dimensional time-dependent Hartree-Fock (TDHF) method. Although the high-spin torus isomer is a unique quantum object characterized by the alignment of angular momenta of independent single-particle motions, we find that the obtained moment of inertia for rotations about an axis perpendicular to the symmetry axis is close to the rigid-body value. We also analyze the microscopic structure of the precession motion using the random-phase approximation (RPA) method for high-spin states. In the RPA calculation, the precession motion of the torus isomer is generated by coherent superposition of many one-particle-one-hole excitations across the sloping Fermi surface that strongly violates the time-reversal symmetry. By comparing results of the TDHF and the RPA calculations, we find that the precession motion obtained by the TDHF calculation is a pure collective motion well decoupled from other collective modes.

Keywords

Cite

@article{arxiv.1311.3775,
  title  = {Pure Collective Precession Motion of High-Spin Torus Isomer},
  author = {T. Ichikawa and K. Matsuyanagi and J. A. Maruhn and N. Itagaki},
  journal= {arXiv preprint arXiv:1311.3775},
  year   = {2015}
}