Heavy-Ion Resonances in Angular-Momentum-Unfavored Channels

The systems ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$+${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ and ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$+${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ have been studied in the inelastic channel leaving ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ in the 6.05-MeV excited $0^{+}$ state. This channel has a grazing angular momentum ∼2.5 units less than the elastic channel. Surprisingly, the excitation functions show pronounced peaks which are closely correlated with the well-matched ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$($3^{-}$, 6.13 MeV) channel. This correlation demonstrates the importance of the wave reflected from the interior of the ion-ion potential.