Unbound spectra of neutron-rich oxygen isotopes predicted by the Gamow shell model

TL;DR

This paper uses the Gamow shell model to analyze neutron-rich oxygen isotopes, emphasizing the importance of continuum coupling in predicting their bound or unbound states, especially near the neutron dripline.

Contribution

It demonstrates the significance of continuum coupling in accurately describing the unbound nature of oxygen isotopes at the dripline, providing new predictions for their excited states.

Findings

$^{28}$O is weakly unbound, similar to $^{26}$O.

Predicted weakly bound and resonance states in $^{24-26}$O.

Different radial properties of bound and unbound states are depicted.

Abstract

The Gamow shell model has shown to efficiently describe weakly bound and unbound nuclear systems, as internucleon correlations and continuum coupling are both taken into account in this model. In the present work, we study neutron-dripline oxygen isotopes. It is hereby demonstrated that the presence of continuum coupling is important for the description of oxygen isotopes at dripline, and especially to assess the eventual bound or unbound character of $^{28}$O. Our results suggest that the ground state of $^{28}$O is weakly unbound and is similar to the narrow resonant $^{26}$O ground state. Predictions of weakly bound and resonance excited states in $^{24\text-26}$O are also provided. The asymptotes of the studied many-body states are analyzed via one-body densities, whereby the different radial properties of well bound, loosely bound, resonance states are clearly depicted.