It is suggested that the de-averaged 180° excitation function of ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ + ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$, recently considered by Frahn and Kaufmann, is strongly model dependent. Within a multistep $\alpha$-transfer description of the back-angle anomaly, we obtain a de-averaged 180° excitation function that exhibits a more regular gross structure.

• Received 8 August 1983

DOI:https://doi.org/10.1103/PhysRevC.29.2383