Figure 1

Differential cross sections of $\alpha +{}^{12}\mathrm{C}$ elastic scattering at (a) $E_{\mathrm{c}.\mathrm{m}.}=1.100$–3.488 MeV and (b) $E_{\mathrm{c}.\mathrm{m}.}=3.638$–4.919 MeV. The solid curves are the results obtained from the optical model with the parity-dependent potential [16]. The number near the curve indicates the incident energy in the center-of-mass system. The experimental data, converted to Rutherford ratio in the center-of-mass system, are taken from [13, 19]. The vertical axis is in log scale.Reuse & Permissions

Figure 2

Schematic diagram of the internal and barrier waves. $U_{\mathrm{eff}}(r)$ is the effective potential, constructed by the nuclear, Coulomb, and centrifugal potentials. “I” and “B” denote the components of the internal wave and barrier wave, respectively. The dashed curve is the tentative absorption $W(r)$ used for the adjustment of the contribution from the internal wave.Reuse & Permissions

Figure 3

Interference between the internal and barrier waves at $E_{\mathrm{c}.\mathrm{m}.}=2.457$ MeV. By varying $R_I$, the contribution from the internal wave is examined. N.A. is the result with nonabsorption, the same as that in Fig. 1. The experimental data are taken from [13, 19].Reuse & Permissions

Figure 4

Excitation functions for $\alpha +{}^{12}\mathrm{C}$ elastic scattering below $E_{\mathrm{c}.\mathrm{m}.}=5$ MeV. The calculated results are shown by the solid curves. The experimental data are taken from [13, 19]. The energy position of the states is indicated by the arrow [21].Reuse & Permissions