Interpretation of Coulomb breakup of 31Ne in terms of deformation

TL;DR

This paper interprets Coulomb breakup data of $^{31}$Ne considering nuclear deformation, suggesting the ground state is likely a halo nucleus with uncertain spin-parity, which could be clarified with more precise neutron separation energy measurements.

Contribution

It provides a deformation-based interpretation of experimental Coulomb breakup data for $^{31}$Ne, proposing possible spin-parity assignments and emphasizing the need for more precise neutron separation energy data.

Findings

Large one-neutron removal cross-section suggests halo structure.

Possible ground state spins are 3/2$^-$ or 1/2$^{+}$, depending on neutron separation energy.

Reducing uncertainty in $S_n$ could clarify the ground state properties.

Abstract

The recent experimental data on Coulomb breakup of the nucleus $^{31}$Ne are interpreted in terms of deformation. The measured large one-neutron removal cross-section indicates that the ground state of $^{31}$Ne is either s- or p-halo. The data can be most easily interpreted as the spin of the ground state being 3/2$^-$ coming from either the Nilsson level [330 1/2] or [321 3/2] depending on the neutron separation energy $S_n$. However, the possibility of 1/2$^{+}$ coming from [200 1/2] is not excluded. It is suggested that if the large ambiguity in the measured value of $S_n$ of $^{31}$Ne, 0.29$\pm1.64$ MeV, can be reduced by an order of magnitude, say to be $\pm$100 keV, one may get a clear picture of the spin-parity of the halo ground state.