Pre-emission ofαParticles in Deep-Inelastic Reactions

In-plane angular and energy correlations between $\alpha$ particles and heavy ejectiles have been measured for the reaction ${}_{}{}^{14}{}_{}{}^{}\mathrm{N}$ + ${}_{}{}^{58}{}_{}{}^{}\mathrm{Ni}$ at 148 MeV. The coincidence cross sections may be parametrized as a product of singles cross sections for the detection of $\alpha$ particles and heavy ejectiles. The observed correlations indicate that the $\alpha$ particles are emitted at an early stage, prior to the formation of the deep-inelastic fragments.