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arXiv · 2403.03713

Nuclear magnetism in the deformed halo nucleus $^{31}$Ne

Cong Pan·Kaiyuan Zhang·Shuangquan Zhang
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Abstract

Based on the point-coupling density functional, the time-odd deformed relativistic Hartree-Bogoliubov theory in continuum (TODRHBc) is developed. Then the effects of nuclear magnetism on halo phenomenon are explored by taking the experimentally suggested deformed halo nucleus $^{31}$Ne as an example. For $^{31}$Ne, nuclear magnetism contributes 0.09 MeV to total binding energy, and the breaking of Kramers degeneracy results in 0-0.2 MeV splitting in canonical single-particle spectra. The blocked neutron level has a dominant component of $p$ wave and it is marginally bound. However, if we ignore nuclear magnetism, the level becomes unbound. This shows a subtle mechanism that nuclear magnetism changes the single-particle energies, causing a nucleus to become bound. Based on the TODRHBc results, a prolate one-neutron halo is formed around the near-spherical core in $^{31}$Ne. The nucleon current is mostly contributed by the halo rather than the core, except near the center of the nucleus. A layered structure in the neutron current distribution is observed and studied in detail.

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Cong Pan, Kaiyuan Zhang, Shuangquan Zhang. 2024-03-06. Nuclear magnetism in the deformed halo nucleus $^{31}$Ne. https://arxiv.org/abs/2403.03713

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