High-spin states in ${}^{35}\mathrm{Ar}$ and ${}^{35}\mathrm{Cl}$ have been populated in the ${}^{24}\mathrm{Mg}$(${}^{16}\mathrm{O}$, $\alpha n$) and ${}^{24}\mathrm{Mg}$(${}^{16}\mathrm{O}$, $\alpha p$) reactions, respectively, at a beam energy of 70 MeV. The comparison between the level schemes of these mirror nuclei shows a striking asymmetry in the population yield of high-spin analog states of positive parity, which indicates different intensities of $E1$ transitions connecting positive- and negative-parity structures in both nuclei. Large energy differences are observed between analog states of negative parity with configurations of dominant pure single-particle character. This results from the comparison with large-scale shell-model calculations in the $s_{1/2}{d}_{3/2}{f}_{7/2}{p}_{3/2}$ valence space. It is shown that important contributions to the energy differences arise from the multipole Coulomb and the relativistic electromagnetic spin-orbit interactions.

• Received 28 November 2006

DOI:https://doi.org/10.1103/PhysRevC.75.034317