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The reactions 48Ti+40Ca at 600, 450 and 300 MeV were employed at the Laboratori Nazionali di Legnaro (LNL) to investigate the charged particles and the Giant Dipole Resonance (GDR) decay of hot rotating 88Mo nuclei. Some preliminary results about Light Charged Particles (LCP) distribution in coincidence with Evaporation Residues (ER) and fusion-fission events selection are shown. [ABSTRACT FROM AUTHOR]

Theoretical description of the experimentally obtained spectra for protons and α-particles and model calculations for the neutron spectra in the reactions with heavy ions has been presented. The hybrid model of non-equilibrium processes was used. Equilibrium evaporation process was analyzed in the framework of the statistical theory of nuclear reactions with Monte-Carlo simulation including certain dynamical and kinematical characteristics. This approach was included in PACE code, which permits to simulate Monte-Carlo de-excitation nuclear process. The Fermi-gas model and level-density phenomenological model for the variation of the nuclear level density parameters was used. In this approach data on 16O+116Sn reaction with Ebeam = 130, 250 MeV were analyzed. Double-differential light charged particle spectra for this reaction were measured using the GARFIELD apparatus in coincidence with evaporation residues. The experimental data were collected in four angular ranges from 29 to 41, 41 to 53, 53 to 67 and 67 to 82 degrees in the laboratory system. The results of the calculations are shown and discussed for these four angular ranges. The contributions from the evaporative and pre-equilibrium processes were analyzed in connection with different nucleus equilibration mechanisms. [ABSTRACT FROM AUTHOR]

The γ-ray emission due to dynamical dipole oscillations during fusion process was measured for the N/Z asymmetric reaction 16O + 116Sn at 8.1 and 15.6 MeV/u. High-energy γ-rays and light charged particles were measured in coincidence with the recoiling residual nuclei. The measured yield of the high-energy γ-rays exceeds that of the thermalized compound nucleus and this extra-yield increases with beam energy. Data are compared with theoretical predictions of a dynamical calculation based on Boltzmann-Nordheim-Vlasov (BNV) model. [ABSTRACT FROM AUTHOR]

High-energy giant dipole resonance (GDR) y rays were measured following the decay of the hot, rotating compound nucleus of 88Mo, produced at excitation energies of 124 and 261 MeV. The reaction 48Ti+ 40Ca at 300 and 600 MeV bombarding energies has been used. The data were analyzed using the statistical model Monte Carlo code GEMINI++. It allowed extracting the giant dipole resonance parameters by fitting the high-energy y-ray spectra. The extracted GDR widths were compared with the available data at lower excitation energy and with theoretical predictions based on (i) The Lublin-Strasbourg drop macroscopic model, supplemented with thermal shape fluctuations analysis, and (ii) The phonon damping model. The theoretical predictions were convoluted with the population matrices of evaporated nuclei from the statistical model GEMINI+-k Also a comparison with the results of a phenomenological expression based on the existing systematics, mainly for lower temperature data, is presented and discussed. A possible onset of a saturation of the GDR width was observed around T = 3 MeV. [ABSTRACT FROM AUTHOR]

A new measurement of the dynamical dipole emission was performed in the system 16O+116Sn at 12 MeV/nucleon. These data, together with those measured at 8.1 MeV/nucleon and 15.6 MeV/nucleon on the same system, provide the dependence of the dynamical dipole total emission yield on the beam energy. The energy removed by preequilibrium charged particles emission was directly measured and this made possible the direct estimation of the compound nucleus excitation energy. The experimental results show a weak increase of the dynamical dipole total yield with beam energy and they are in agreement both in trend and in absolute values with the predictions of the theoretical model based on the Boltzmann-Nordheim-Vlasov approach. The measured γ-ray angular distribution has a dipole character but with a strong quenching probably owing to the rotation of the dipolar axis during the fusion and thermalization processes [ABSTRACT FROM AUTHOR]

The article presents the study which analyzed the odd-even staggering effects on charge distributions for fragments produced in semiperipheral and central collisions of 112tin (Sn) + 58Nickel (Ni) at 35 megaelectron-volts (MeV)/nucleon. It claims that the odd-even staggering phenomena occurred in fragments produced in heavy-ion collisions at intermediate energies. The CHIMERA multidetector was used in the study.