Target-like reaction products corresponding to the transfer of one or several nucleons have been measured as a function of the total kinetic energy loss in the reactions Pb+' Ni (1215 MeV) and Pb+ Ni (1107 MeV) with a focusing time-of-flight spectrometer which provided a unique mass and charge separation and good energy resolution. The analysis of the experimental data covered the range from elastic scattering to deep-inelastic collisions. In the quasielastic region, neutron transfer dominates. The transfer probabilities as a function of the distance of closest approach can be described by a semiclassical theory of tunneling. Quasielastic transfer from the Ni targets to the 0 Pb projectile is strongly inhibited by the reaction Q values. For the intermediate and deepinelastic collisions, the mean values and variances of the mass and charge distributions as a function of the dissipated energy, as well as the correlations between neutron and proton transport, are discussed in a statistical diffusion theory. The important influence of the static potential energy surface on nucleon transport in the deep-inelastic region is demonstrated. Deviations from the simple diffusion model, observed at small to medium energy losses, are discussed.

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The multiplicities of neutrons emitted from the light and heavy fragments, respectively, in the inelastic scattering of 7.5 MeV/amu 132Xe ions from 197Au have been studied as a function of total energy loss. The measured multiplicity ratios are close to the Au-Xe mass ratio for all Q-values, consistent with a rapid thermalization of the excitation energy. The absolute multiplicity values are lower than expected and suggest significant pre-equilibrium effects.