[en] The emission of fragments ranging from ₂₄Na to ₅₂Mn in reactions of 18.5 GeV ₁₂C ions with Cu, Ag, Gd, Ta, Au, and U targets has been studied by means of activation techniques. The experiments involved determination of the fragment production cross sections and thick-target recoil properties. The latter were used to obtain mean fragment kinetic energies and the forward velocity component of the struck nucleus (in units of c). The results are compared with similar data for incident protons of the same total kinetic energy