Excitation functions have been measured for the elastic scattering of ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$ + ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ at 180° and 90°. The excitation functions at the two angles are found to be anticorrelated, an effect which is quite similar to that observed previously in ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$ + ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ and ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$ + ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ elastic scattering. It is found from distorted-wave Born-approximation analyses of the energy dependence that the one-step elastic transfer process is probably not responsible for the observed resonancelike structure around 180° nor for the anticorrelation in the excitation functions at the two angles in ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$ + ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ scattering.

NUCLEAR REACTIONS Elastic scattering of ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$ + ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$; measured $\sigma (E,180\mathrm{}°)$ and $\sigma (E,90\mathrm{}°)$; DWBA analysis for the elastic transfer reaction ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$(${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$, ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$).

• Received 17 September 1979

DOI:https://doi.org/10.1103/PhysRevC.21.459