Resonancelike structures are observed at backward angles for elastic scattering of ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ + ${}_{}{}^{32}{}_{}{}^{}\mathrm{S}$ and for the reaction ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$(${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$, ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$)${}_{}{}^{32}{}_{}{}^{}\mathrm{S}$ which are uncorrelated with the ones seen in the system ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ + ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$. Analysis of angular distributions indicates that forward $\alpha$ transfer is dominated by partial waves different from those of backward-angle $\alpha$ transfer and elastic scattering in the entrance and exit channels.

• Received 7 July 1978

DOI:https://doi.org/10.1103/PhysRevLett.41.1778