O18+C12System: Evidence for Nonstatistical Intermediate Structure with Enhancement of Odd Partial Waves in the Elastic Channel

${}_{}{}^{18}{}_{}{}^{}\mathrm{O}$ + ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ elastic-scattering excitation functions have been measured at eight angles over the energy range 12-25 MeV (c.m.). In addition, cross sections for the reaction channels ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}({}_{}{}^{18}{}_{}{}^{}\mathrm{O}, \alpha ){}_{}{}^{26}{}_{}{}^{}\mathrm{Mg}$ ($E_x=0.0-5.47\mathrm{}$ MeV) and ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$(${}_{}{}^{18}{}_{}{}^{}\mathrm{O}$, ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$)${}_{}{}^{14}{}_{}{}^{}\mathrm{C}$ were measured over nearly the same energy range. The elastic scattering exhibits the novel behavior of being dominated by odd partial waves. Correlated structures were observed at 16.6, 19.0 ($J^{\pi }={15}^{-}$), and 21.8 ($J^{\pi }={17}^{-}$) MeV (c.m.).