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Inelastic scattering of Ca-40 on Ca-40 at 50 MeV/nucleon has been measured in coincidence with Light charged particles detected over a large angular domain. The giant resonance region of the inelastic spectrum is shown to be dominated by the isoscalar giant quadrupole resonance. The characteristics of the emitted protons allow us to separate four reaction mechanisms contributing to the high excitation energy region of the inelastic spectrum (E* > 30 MeV): pickup breakup, knockout, inelastic scattering to high-lying target states, and a new mechanism responsible for the emission of fast-moving protons. A sizable direct decay branch towards hole states of K-39 is measured for the giant quadrupole resonance in Ca-40. Evidence is given for the excitation of the two-phonon giant quadrupole resonance, characterized by its direct decay scheme. The energy and width of this two-phonon state are in agreement with a harmonic picture for collective nuclear excitations.

A study of the reaction Ca-48(Ne-20,Ne-19 n) at 48A MeV has been performed at the GANIL facility. The inclusive excitation spectrum above 12 MeV excitation is dominated by a broad structureless bump. Calculations performed in the framework of the Bonaccorso-Brink model predict that the absorption process (transfer +inelastic breakup) dominates over the elastic breakup process. Comparison of the neutron multiplicity calculated in a statistical model with the measured one confirms a significant contribution of the direct processes (elastic and inelastic breakup). The neutron yield to the ground state of the Ca-48 is maximal in the forward direction. Comparisons with calculated neutron angular distributions show the effect of the final state interaction.

The neutron decay of the continuum in Zr-90 and Sn-124, excited by inelastic scattering of 84A MeV O-17 ions in the range from 1.5 to 4.5-degrees, has been measured. Statistical decay was found to dominate the excitation-energy interval studied, up to about 50 MeV. In the excitation-energy interval from the neutron threshold up to about 35 MeV a distinct direct-decay component to the hole states in Zr-89 and Sn-123 was observed. In addition, a decay pattern resembling pre-equilibrium decay was observed for Zr-90. In the excitation energy spectrum of Zr-90 gated by low-energy (

Inelastic scattering of 50 MeV/nucleon Ca-40 on Ca-40 was measured in coincidence with protons in order to investigate the excitation and decay of highly excited states in Ca-40. The proton decay pattern corresponding to an excitation region around 34 MeV shows the characteristic behavior expected of the direct decay of a two-phonon state. Thus, by using this novel method, the presence of a double-phonon state built with isoscalar giant resonances in Ca-40 is demonstrated.

Elastic and inelastic scattering of 1435 MeV 170 ions on Pb-208, Sn-120, Zr-90 and Ni-60 have been measured. Hindrance in the excitation of the first 3- states is observed. Parameters of the isoscalar giant monopole and quadrupole resonances are obtained. The quadrupole resonance exhausts approximately 55% of the energy-weighted sum rule while the observed monopole resonance corresponds to more than 100% of the sum rule. Strength is also observed at high excitation energy in all targets.

The emission of hard photons and pre-equilibrium protons has been investigated in exclusive experiments performed with MEDEA detector The observation of the gamma-proton anticorrelation indicates that the dominant production mechanism is the first-chance neutron-proton (np) collisions. The anisotropic angular distributions point out the presence of screening effects and are reminiscent of the free np scattering thus giving information of the space-time origin of the energetic protons. Protons, with energy more than twice the kinematical limit for nucleon-nucleon (NN) collisions, have been observed in several reactions around the Fermi energy.