Excitation functions of the reaction ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}({}_{}{}^{12}{}_{}{}^{}\mathrm{C}, \alpha ){}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$ have been measured in 50-keV energy steps from $E_{\mathrm{c}.\mathrm{m}.\mathrm{}}=4.0-8.0\mathrm{}$ MeV at 15 angles between ${\theta }_{\mathrm{c}.\mathrm{m}.\mathrm{}}=6\mathrm{}° \mathrm{and} 90°$. From the angle-integrated cross sections of the first six transitions to ${}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$ the following resonance energies have been deduced: $E_{\mathrm{c}.\mathrm{m}.\mathrm{}}=4.25, 4.46, 4.62, 4.88, 5.0, 5.64, 5.92, \mathrm{and} 6.25$ MeV. The spin-parity assignments for these resonances have been determined to be $0^{+}$, $4^{+}$ ($2^{+}$), $2^{+}$, $2^{+}$, $2^{+}$, $2^{+}$, $4^{+}$, and $2^{+}$, respectively.

NUCLEAR REACTIONS ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}({}_{}{}^{12}{}_{}{}^{}\mathrm{C}, \alpha )$, $E=4-8\mathrm{}$ MeV, measured $\sigma (\theta , E)$, extracted resonance energies and $J^{\pi }$ values.

• Received 7 October 1976

DOI:https://doi.org/10.1103/PhysRevC.15.950