Structure and decay of the extremely proton-rich nuclei O 11,12

Background: The recent observation of the unbound nucleus O11 offers the unique possibility to study how the structure and dynamics of two-proton (2p) decay is affected by the removal of one neutron from O12, and provides important information on the Thomas-Ehrman effect in the mirror pairs O3811-Li8311 and O4812-Be8412, which involve the 2p emitters O11 and O12. Purpose: We investigate how continuum effects impact the structure and decay properties of O11 and O12, and their mirror partners. Methods: We solve the three-body core-nucleon-nucleon problem using the Gamow coupled-channel (GCC) method. The GCC Hamiltonian employs a realistic finite-range valence nucleon-nucleon interaction and the deformed cores of C9,10, Li9, and Be10. Results: We calculate the energy spectra and decay widths of O11 and O12 as well as those of their mirror nuclei. In particular, we investigate the dynamics of the 2p decay in the ground state of O12 by analyzing the evolution of the 2p configuration of the emitted protons as well as their angular correlations in the coordinate space. We also show how the analytic structure of the resonant states of Li10 and N10 impacts the low-lying states of Li11 and O11. Conclusions: We demonstrate that, in both nuclei O11 and O12, there is a competition between direct and "democratic" 2p ground-state emission. The broad structure observed in O11 is consistent with four broad resonances, with the predicted 3/21- ground state strongly influenced by the broad threshold resonant state in N10, which is an isobaric analog of the antibound (or virtual) state in Li10.