  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.
