Quasimolecular states in theC12-C12system

Quasimolecular resonance structures in the ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$-${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ system are studied in the framework of the coupled channel formalism in the energy range $E_{\mathrm{c}.\mathrm{m}.\mathrm{}}=5\mathrm{}-14$ MeV. The influence of the coupling of the first excited $2^{+}$ state in ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ on the resonance structures is investigated by choosing various types of coupling potentials. The intermediate structures in the reflection and transition coefficients and cross sections can be interpreted with the double resonance mechanism.