The emission of energetic light ions from heavy-ion induced reactions was studied by measuring coincidences of protons and alpha particles with (1) $Z=1\mathrm{} \mathrm{to} 7$ particles, (2) discrete $\gamma$ rays, and (3) $\gamma$-ray multiplicities from bombardment of ${}_{}{}^{60}{}_{}{}^{}\mathrm{Ni}$ with ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ ions. Incident beam energies were 136 and 194 MeV. Discrete $\gamma$ rays were used to identify the residual targetlike fragments. Most of the particle-particle coincident angular correlations are strongly peaked in the forward direction; the full widths at half maximum of the proton distributions are typically 50°, those of the alpha particles are 30°. The $N-Z$ distributions of the residual nuclei peak around ${}_{}{}^{60}{}_{}{}^{}\mathrm{Ni}$. The $\gamma$-ray multiplicities are insensitive to the energy of the gating energetic light ion and are about 9 for 136-MeV ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ projectiles and 10 for 194 MeV. The results indicate the contribution of more than one mechanism in producing the high-energy light ions. In part the energetic light ions are emitted in association with a projectilelike fragment. A major component of the energetic light ions can be explained as emission from the projectilelike fragment during the collision process followed by fusion of the remainder of the fragment with the target.

NUCLEAR REACTIONS ${}_{}{}^{60}{}_{}{}^{}\mathrm{Ni}$(${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$,$p$), (${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$,$\alpha$) $E=136, 194$ MeV; measured $\sigma (E,\theta )$ in coincidence with $Z=1-6\mathrm{}$ particles, $\gamma$ rays and $\gamma$ multiplicities.

• Received 17 July 1981

DOI:https://doi.org/10.1103/PhysRevC.24.2084