Optical-model description ofO16+Si28elastic scattering at backward angles

The large, oscillating backward angle cross sections that have been observed in recent ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ + ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$ elastic data at $E\left({}_{}{}^{16}{}_{}{}^{}\mathrm{O}\right)=50\mathrm{} \mathrm{and} 55$ MeV are reproduced in an optical-model analysis using Woods-Saxon potentials.