I have used a potential model to examine mirror states in ${}^9\mathrm{Li}$ and ${}^9\mathrm{C}$. The mirror energy difference and observed widths of the supposed $7/2^{-}$ states are consistent with dominant parentage to the $3^{+}$ excited state of ${}^8\mathrm{Li}$ and ${}^8\mathrm{B}$. The newly reported $s$-wave resonance at 4.3 MeV in ${}^9\mathrm{C}$ should have a mirror near $E_x=5.39\left(38\right)\mathrm{MeV}$ in ${}^9\mathrm{Li}$.

• Received 30 April 2019
• Revised 18 June 2019

DOI:https://doi.org/10.1103/PhysRevC.100.014321