Elastic excitation function ofC12onCa40at 180°

An excitation function of elastically scattered ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ from ${}_{}{}^{40}{}_{}{}^{}\mathrm{Ca}$ at ${\theta }_{\mathrm{c}.\mathrm{m}.\mathrm{}}=180\mathrm{}°$ was measured at 10 center-of-mass energies between 30.0 and 34.2 MeV to observe whether the anomalous structure that was seen in the back-angle excitation function of ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ and ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ on ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$ also existed in this system. The cross section is ∼${10}^{-4\mathrm{}}$ times that for Rutherford scattering, which is about two orders of magnitude lower than was seen with ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$. A resonance-like energy dependence was observed.