Low lying resonances in the unbound nuclei ${}^{11}\mathrm{N}$ and ${}^{15}\mathrm{F}$ have been calculated using a conventional Woods-Saxon potential plus a surface term deduced from the mirror nuclei ${}^{11}\mathrm{Be}$ and ${}^{15}\mathrm{C},$ respectively. Calculations for ${}^{11}\mathrm{N}$ are in good agreement with experimental results showing that both a halo nucleus and its unbound mirror nucleus can be described simultaneously. For the ${}^{13}\mathrm{C}$ and ${}^{13}\mathrm{N}$ mirror nuclei where the surface term is weaker we have checked that our results are similar to what was previously obtained with pure Woods-Saxon potentials. Within the same approach, two ${1/2}^{+}$ and ${5/2}^{+}$ narrow resonances are predicted in ${}^{15}\mathrm{F},$ mirror of ${}^{15}\mathrm{C},$ at 1.2 and 2.35 MeV, also in agreement with measurements.

• Received 14 April 1997

DOI:https://doi.org/10.1103/PhysRevC.56.2885