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arXiv · 1207.6250

Existence of exotic torus configuration in high-spin excited states of $^{40}$Ca

T. Ichikawa·J. A. Maruhn·N. Itagaki·K. Matsuyanagi·P. -G. Reinhard·S. Ohkubo
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Abstract

We investigate the possibility of the existence of the exotic torus configuration in the high-spin excited states of $^{40}$Ca. We here consider the spin alignments about the symmetry axis. To this end, we use a three-dimensional cranked Skyrme Hartree-Fock method and search for stable single-particle configurations. We find one stable state with the torus configuration at the total angular momentum $J=$ 60 $\hbar$ and an excitation energy of about 170 MeV in all calculations using various Skyrme interactions. The total angular momentum J=60 $\hbar$ consists of aligned 12 nucleons with the orbital angular momenta $Λ=+4$, +5, and +6 for spin up-down neutrons and protons. The obtained results strongly suggest that a macroscopic amount of circulating current breaking the time-reversal symmetry emerges in the high-spin excited state of $^{40}$Ca.

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T. Ichikawa, J. A. Maruhn, N. Itagaki, K. Matsuyanagi, P. -G. Reinhard, S. Ohkubo. 2012-07-26. Existence of exotic torus configuration in high-spin excited states of $^{40}$Ca. https://doi.org/10.1103/physrevlett.109.232503

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