Resonances in the ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$-${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ system and in the energy range $E_{\mathrm{c}.\mathrm{m}.\mathrm{}}=7-10\mathrm{}$ MeV were studied through $\gamma$ decay. Excitation functions of the $\gamma$ decay of the first excited states of ${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$, ${}_{}{}^{23}{}_{}{}^{}\mathrm{Na}$, and ${}_{}{}^{23}{}_{}{}^{}\mathrm{Mg}$ seen through the ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$(${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$,$\alpha$)${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$, ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$(${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$,$p$)${}_{}{}^{23}{}_{}{}^{}\mathrm{Na}$, and ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$(${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$,$n$)${}_{}{}^{23}{}_{}{}^{}\mathrm{Mg}$ reactions corroborated the existence of resonances observed through various particle reactions. With the help of angular distributions from the ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$(${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$,$\alpha$)${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}_{\mathrm{g}.\mathrm{s}.\mathrm{}}^{}{}_{}{}^{}$ reaction, one other resonance was established at $E_{\mathrm{c}.\mathrm{m}.\mathrm{}}=9.65\mathrm{}$ MeV with $J^{\pi }=8^{+}$.

NUCLEAR REACTIONS ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$(${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$,$\alpha$)${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$, ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$(${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$,$p$)${}_{}{}^{23}{}_{}{}^{}\mathrm{Na}$, ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$(${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$,$n$)${}_{}{}^{23}{}_{}{}^{}\mathrm{Mg}$; $E\left({}_{}{}^{12}{}_{}{}^{}\mathrm{C}\right)=14-20\mathrm{}$ MeV; measured ${\sigma }_{\gamma }\mathrm{}\left(E\right)\mathrm{}$, ${\sigma }_{\alpha }(E,\vartheta )$, deduced ${}_{}{}^{24}{}_{}{}^{}\mathrm{Mg}$ resonances; natural target.

• Received 7 May 1979

DOI:https://doi.org/10.1103/PhysRevC.21.1648