Recoil effects in peripheral nucleus-nucleus collisions at E/A=84 MeV

Abstract Azimuthal angular correlations between projectile fragments and light particles have been measured in 18 O induced reactions on 58.64 Ni and 197 Au targets at E / A =84 MeV. Neither sequential projectile decay nor evaporation from an equilibrated target-like recoil can explain the observed correlations. The data are well described in terms of a sideways-moving source suggesting emission of midrapidity light particles from a subset of nucleons which carries a major part of the transverse recoil momentum imparted by the projectile fragment.