We perform coupled-cluster calculations of the energies and lifetimes of single-particle states around the doubly magic nucleus ${}^{16}\mathrm{O}$ based on chiral nucleon-nucleon interactions at next-to-next-to-next-to-leading order. To incorporate effects from the scattering continuum, we employ a Gamow-Hartree-Fock basis. Our calculations for the $J^{\pi }=1/2^{+}$ proton halo state in ${}^{17}\mathrm{F}$ and the $1/2^{+}$ state in ${}^{17}\mathrm{O}$ agree well with experiment, while the calculated spin-orbit splitting between $5/2^{+}$ and $3/2^{+}$ states is too small due to the lack of three-nucleon forces. Continuum effects yield a significant amount of additional binding energy for the $1/2^{+}$ and $3/2^{+}$ states in ${}^{17}\mathrm{O}$ and ${}^{17}\mathrm{F}$.

• Received 9 March 2010

DOI:https://doi.org/10.1103/PhysRevLett.104.182501