Angular distributions and excitation functions for ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}({}_{}{}^{12}{}_{}{}^{}\mathrm{C},\alpha ){}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}$ and ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$(${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$, ${}_{}{}^8{}_{}{}^{}\mathrm{Be}$)${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ have been measured around $E_{12C}(\mathrm{c}.\mathrm{m}.\mathrm{})=18.5\mathrm{}$ MeV, where strongly correlated structure for both reactions has been reported. Both ground-state angular distributions are dominated by a single angular momentum; for ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}({}_{}{}^{12}{}_{}{}^{}\mathrm{C},\alpha ){}_{}{}^{20}{}_{}{}^{}\mathrm{Ne}_{\mathrm{g}.\mathrm{s}.\mathrm{}}^{}{}_{}{}^{}$ the dominant angular momentum is $l=10\mathrm{}$, while for ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$(${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$, ${}_{}{}^8{}_{}{}^{}\mathrm{Be}_{\mathrm{g}.\mathrm{s}.\mathrm{}}^{}{}_{}{}^{}$) ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}_{\mathrm{g}.\mathrm{s}.\mathrm{}}^{}{}_{}{}^{}$ it is $l=12\mathrm{}$. Hauser-Feshbach calculations reproduce the shapes of the angular distributions; the dominant angular momenta are the grazing partial waves in the outgoing channels.

NUCLEAR REACTIONS ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$(${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$, ${}_{}{}^8{}_{}{}^{}\mathrm{Be}$), (${}_{}{}^{12}{}_{}{}^{}\mathrm{C},\alpha$), $E=36.5-37.5\mathrm{}$ MeV; measured $\sigma (E, \theta )$. Hauser-Feshbach calculations.

• Received 6 August 1975

DOI:https://doi.org/10.1103/PhysRevC.13.440