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An iterative method for the determination of the charged particle loss as a function of the reactionQ-value is developped. The analysis is based on experimental data resulting from 400 MeV40Ca+40Ca collisions.Z distributions are obtained at different calculatedQ-values corrected for evaporation and show rather good agreement — in the strongly damped case — with the ones derived from the OVERLAID ALICE code. Mean numbers of evaporated particles exhibit a linear increase as a function of these correctedQ-values; this corresponds to the evolution from quasi-direct to fully relaxed reactions.

Evidence is presented for the observation of four structures in the incompletely relaxed part of the energy spectra of fragments emitted in the40Ca+40Ca reaction at 400 MeV. These structures appear to be produced in a direct process. Statistical evaporation processes from primary fragments cannot explain all the observed structures. Excitation of giant resonances is a plausible interpretation.

Out-of-plane correlations between a-particles and projectile-like heavy ions have been measured for the system32S+197Au at ELAB=373 MeV. The angular widths of the correlations range from 24° to 40° (FWHM) depending on theZ of the heavy ion. In the framework of a model calculation these widths are shown to be very sensitive to the outof-plane momentum of the a-particle at emission. It is concluded that only little heating of the reaction partners occurs prior to a-particle emission.

The general symmetry properties of theT-matrix due to the exchange of identical cores in nuclear reactions between composite particles are given. For the case of direct transfer reactions an explicit expression for the cross section is derived in the distorted wave Born approximation. In this model the cross section is the coherent sum of two indistinguishable transfer processes. The relative phase between the corresponding transfer amplitudes is obtained from the Pauli principle and depends on the signs of the spectroscopic amplitudes which may, therefore, be determined experimentally.

The transfer of neutrons between low-lying states of Tin isotopes has been measured in the reaction120Sn?112Sn at energies below the Coulomb barrier. The transfer probabilities are deduced as function of the classical minimum distance from transfer and scattering cross sections at different angles and two energies. At the smallest distances very large transfer probabilities,pt=0.5, are observed for one- and two-neutron transfer. The two-neutron transfer is significantly enhanced as compared to a successive independent single-nucleon transfer. The definition of enhancement is discussed.

Angular and energy correlations betweena-particles and deep-inelastic projectile-like fragments were measured for the system36Ar+197Au atELab=380 MeV. At most half of the coincident events can be attributed to statistical emission ofa-particles from the fully accelerated projectile-like fragments. The remainder of the events may be due to direct emission during the first 10-22 s of the scattering process and to preequilibrium processes taking place within some 10-21 s.

Energy spectra of fragments from the36Ar+208Pb reaction at 11 MeV/n exhibit structures at high excitation energies. These structures are interpreted in terms of target multi-phonon excitations built from giant resonances. The importance of such processes for the kinetic energy dissipation in heavy ion collisions is emphasized.

Inelastic spectra from the36Ar+208Pb reaction at 11 MeV/n and20Ne+208Pb at 30 MeV/n have been measured with a time of flight spectrometer. Structures ranging up to 100 MeV excitation energy are observed together with previously known giant resonance excitations. Transfer-evaporation reactions are shown to contribute only to the background under the structures. These structures are interpreted in terms of an excitation of the target nucleus through a direct process.

Angular and energy correlations betweena-particles and quasi-elastic projectile-like heavy ions have been measured for36Ar+197Au collisions atELAB=380MeV.

Angular correlations between light charged particles and heavy ion fragments from the40Ca+40Ca collision have been investigated. The high excitation energy structure previously observed in inclusive experiments is strongly populated in coincidence with protons for calcium and potassium fragments, with alphas for argon fragments. Particles emitted in coincidence with the structure are strongly focused and have a velocity close to the velocity of the beam, whereas the yield of evaporation decay is very small.

Evaporation residue cross sections for the fusion of52Cr and110Pd were studied at four energies close to the barrier (up toECM-EB=26 MeV). The cross sections were analysed using a multiple-chance fission/evaporation calculation. Agreement with the data is obtained with a fission barrier reduced by 40 to 20%, depending on incident energy.