Ab-initio no-core shell model study of $^{18-24}$Ne isotopes

TL;DR

This study uses ab initio no-core shell model calculations with three realistic interactions to analyze energy spectra, electromagnetic properties, and radii of neon isotopes, achieving good agreement with experimental data.

Contribution

It provides comprehensive ab initio calculations of neon isotopes up to Nmax=6 using three different realistic NN interactions, extending previous models.

Findings

Better binding energy results with INOY interaction.

Good agreement with experimental spectra and magnetic moments.

Long-range observables require larger model spaces for convergence.

Abstract

We report \textit{ab initio} no-core shell model (NCSM) study of $^{18-24}$Ne isotopes for energy spectra, electromagnetic properties, and point-proton radii using three realistic $NN$ interactions. We have used inside nonlocal outside Yukawa (INOY), charge-dependent Bonn 2000 (CDB2K) and the chiral next-to-next-to-next-to-leading order (N$^3$LO) interactions. We are able to reach basis size up to $N_{max}$ = 6 for $^{18}$Ne and $N_{max}$ = 4 for the $^{19-24}$Ne isotopes with m-scheme dimensions up to 1.0 $\times$ $10^9$ in case of $^{24}$Ne. We observed better results for INOY interaction in terms of the binding energies of ground state (g.s.), and overall all three interactions provide good agreement with the experimental low-energy spectra. Our results for reduced $M1$ transition strengths and magnetic moments are close to the experimental values. We found that for long-range observables such as the $E2$ transition strengths, the electric quadrupole moments, and the point-proton radii ($r_p$), we need higher $N_{max}$ calculations to obtain results comparable to the experimental data. We have observed almost 6 \% increment in the converged $r_p$ as we increase the model space from $N_{max}$ = 4 to $N_{max}$ = 6.