Improving the sd-shell effective interaction obtained from the Daejeon16 nucleon-nucleon interaction

Abstract

We present new microscopic effective shell-model interactions in the valence $sd$ shell, obtained from the modern Daejeon16 nucleon-nucleon potential using no-core shell-model (NCSM) wave functions of ${}^{18}\mathrm{F}$ at $N_{\max }=6$ (total oscillator quanta of excitation) model space and the Okubo-Lee-Suzuki transformation. First, we explore the convergence properties of our calculations and show that the excitation energies of states in ${}^{18}\mathrm{F}$, characterized by the largest valence-like configurations, are reasonably converged and the lowest states are in sensible agreement with experiment. Then, we investigate the monopole properties of that interaction in comparison with the phenomenological universal $sd$-shell interaction, USDB, and with the previously derived interaction at $N_{\max }=4$. Theoretical binding energies and low-energy spectra of the O isotopes, as well as low-energy spectra of a selection of $sd$-shell nuclei, are presented. We conclude that the use of larger-space NCSM wave functions leads to a noticeable improvement in the quality of the derived effective interaction. We propose monopole modifications of the Daejeon16 centroids which further improve the agreement with experiment throughout the $sd$ shell, as demonstrated by a compilation of spectra contained in Supplemental Material.