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arXiv · 2208.00816

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

Chandan Sarma·Praveen C. Srivastava
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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.

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Chandan Sarma, Praveen C. Srivastava. 2022-08-01. Ab-initio no-core shell model study of $^{18-24}$Ne isotopes. https://doi.org/10.1088/1361-6471%2Facb962

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