Intermediate-Structure Effects in the ReactionC12(O16,Ne20)Be8

We have measured the angular distributions of the reaction ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$(${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$, ${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$)${}_{}{}^8{}_{}{}^{}\mathrm{Be}$ in the c.m. energy range 12.22 to 15.07 MeV. The data and analysis, indicate a broad (${\Gamma }_1\simeq 650$ keV) $L=8\mathrm{}$ resonancelike structure centered at $E_1\simeq 13.15$ MeV. The severe damping of the $L=8\mathrm{}$ structure of the angular distribution and the deep minimum in the integrated cross section at $E_2\simeq 13.7$ MeV appear to be due to interference between the broad resonance at $E_1$ and a narrow (${\Gamma }_2\simeq 100$ keV) $L=8\mathrm{}$ resonance at $E_2$. This interpretation is consistent with two-level $R$-matrix fits.