Collapse of the $N=28$ shell closure in the newly discovered ${}^{39}$Na and the development of deformed halos towards the neutron dripline

Abstract

Halos and changes of nuclear magicities have been extensively investigated in exotic nuclei during past decades. The newly discovered ${}^{39}$Na with the neutron number $N=28$ provides a new platform to explore such novel phenomena near the neutron dripline of the sodium isotopic chain. We study the shell property and the possible halo structure in ${}^{39}$Na within the deformed relativistic Hartree-Bogoliubov theory in continuum. It is found that the lowering of $2p$ orbitals in the spherical limit results in the collapse of the $N=28$ shell closure in ${}^{39}$Na, and a well deformed ground state is established. The pairing correlations and the mixing of $pf$ components driven by deformation lead to the occupation of weakly bound or continuum $p$-wave neutron orbitals. An oblate halo is therefore formed around the prolate core in ${}^{39,41}$Na, making ${}^{39}$Na a single nucleus with the coexistence of several exotic structures, including the quenched $N=28$ shell closure, Borromean structure, deformed halo, and shape decoupling. The microscopic mechanisms behind the shape decoupling phenomenon and the development of halos towards dripline are revealed.

8 pages, 5 figures

References in corpus (23)

• Relativistic Continuum Hartree Bogoliubov Theory for Ground State Properties of Exotic Nuclei
• New parametrization for the nuclear covariant energy density functional with point-coupling interaction
• Hidden pseudospin and spin symmetries and their origins in atomic nuclei
• Collapse of the N=28 shell closure in ${}^{42}$Si
• Microscopic justification of the Equal Filling approximation
• Deformed relativistic Hartree-Bogoliubov theory in continuum with point coupling functional: examples of even-even Nd isotopes
• A two-neutron halo is unveiled in ${}^{29}$F
• Quasi-free Neutron Knockout Reaction Reveals a Small $s$-orbital Component in the Borromean Nucleus ${}^{17}$B
• Energy Density Functional analysis of shape evolution in N=28 isotones
• Study of ground state properties of carbon isotopes with deformed relativistic Hartree-Bogoliubov theory in continuum
• Predictive power for superheavy nuclear mass and possible stability beyond the neutron drip line in deformed relativistic Hartree-Bogoliubov theory in continuum
• Odd systems in deformed relativistic Hartree Bogoliubov theory in continuum
• Deformed relativistic Hartree-Bogoliubov theory in continuum with a point-coupling functional. II. Examples of odd Nd isotopes
• Density-dependent deformed relativistic Hartree-Bogoliubov theory in continuum
• Possible bound nuclei beyond the two-neutron drip line in the $50⩽Z⩽70$ region
• Neutron drip line in the deformed relativistic Hartree-Bogoliubov theory in continuum: Oxygen to Calcium
• Shape coexistence and neutron skin thickness of Pb isotopes by the deformed relativistic Hartree-Bogoliubov theory in continuum
• Angular momentum projection in the deformed relativistic Hartree-Bogoliubov theory in continuum
• Optimized Dirac Woods-Saxon basis for covariant density functional theory
• Bubble nuclei with shape coexistence in even-even isotopes of Hf to Hg
• Electric dipole response of low-lying excitations in the two-neutron halo nucleus ${}^{29}$F
• Density matrix renormalization group description of the island of inversion isotopes ${}^{28-33}$F
• Constraints on the neutron drip-line with the newly observed 39Na

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