Measurements of the yields of ${}_{}{}^{6,7}{}_{}{}^{}\mathrm{Li}$ and ${}_{}{}^{7,9}{}_{}{}^{}\mathrm{Be}$ have been made for the ${}_{}{}^{14}{}_{}{}^{}\mathrm{N}$ + ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ reaction at $E_{{}_{}{}^{14}{}_{}{}^{}\mathrm{N}}=86.9\mathrm{} \mathrm{and} 157.0$ MeV. Statistical model calculations are compared with the data in order to determine the reaction mechanism. It is concluded that more than half of the total Li and Be yield at these bombarding energies arises from processes other than compound nucleus formation and the subsequent evaporation of a ${}_{}{}^{6,7}{}_{}{}^{}\mathrm{Li}$ or ${}_{}{}^{7,9}{}_{}{}^{}\mathrm{Be}$ nucleus. The most likely production mechanism at high bombarding energies appears to be the decay of a projectile-like fragment excited in a peripheral collision.

NUCLEAR REACTIONS ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$(${}_{}{}^{14}{}_{}{}^{}\mathrm{N}$, ${}_{}{}^{6,7}{}_{}{}^{}\mathrm{Li}$), ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$(${}_{}{}^{14}{}_{}{}^{}\mathrm{N}$, ${}_{}{}^{7,9}{}_{}{}^{}\mathrm{Be}$), $E=86.9\mathrm{} \mathrm{and} 157.0$ MeV; measured $\sigma (E,\theta )$; compared with statistical model calculations.

• Received 23 May 1977

DOI:https://doi.org/10.1103/PhysRevC.16.2249