Sources of light particles in peripheral collisions

By studying light charged particles emitted in coincidence with projectile-like fragments, we probe heavy ion reaction mechanisms that result in the production of light particles in peripheral collisions. Triple coincidence α-α${\mathrm{-}}^{12}$C correlations in the reactions of 35 MeV/nucleon ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ with Ni conclusively identify previously known sources of light particles. The fast, beam velocity component of α particles in coincidence with projectile-like fragments is associated with the breakup of the projectile. The correlations suggest that the origin of the intermediate velocity component of α particles is the target nucleus. Both of these components are characterized by α particles emitted during the early stages of the collision.