No abstract available

No abstract available

[en] Gamma-rays emitted from hot nuclei with mass around 115 and excitation energies above 300 MeV, formed in the ³⁶Ar + ⁹⁸Mo reaction at 37 AMeV, have been measured. A comparison with previous experiments at lower bombarding energies shows a decrease of the γ-yield with increasing incident energy. A tentative interpretation based on dynamical calculations is proposed

[en] Investigation of unbound nuclear systems 9He, 7H and 4n was performed at GANIL-SPIRAL using the 8He beam at 15.3 A MeV and a CD2 target. The missing mass spectra were deduced from kinetic energies and emission angles of light ejectiles detected by the Silicon array MUST. In addition to previously known low-lying narrow resonant states in 9He, the d(8He,p) reaction displays a structure just above neutron emission threshold, identified with the 'true' ground state of 9He. The analysis of angular distributions shows that the inversion of s1/2 and p1/2 neutron shells previously observed in 11Be and 10Li also exists in the lightest N=7 isotone 9He. The d(8He,3He) and d(8He,6Li) reactions were used to search for resonant states in the t+4n (7H) and 4n systems, respectively. The missing mass spectrum of the 4n system does not give evidence for the existence of a bound 'tetraneutron'. However the comparison with the results of 5-body phase-space calculations emphasizes the existence of correlations in the 4n system. The broad structure observed at ≅2 MeV above the t+4n emission threshold is proposed to be the ground state of 7H

[en] The structure of the light unstable nuclei ^10,11C and ^6,8He is investigated by means of (p,p') reactions. The experiments were performed at GANIL using the MUST detector, an array of Si and SiLi telescopes. The (p,p') are analyzed within the framework of the microscopic JLM potential, allowing to test the densities predicted by structure models. Preliminary data from the ⁸He(p,o') reaction performed at the SPIRAL facility at 15.6 MeV/nucleon are discussed

No abstract available

[en] γ-ray production cross sections have been measured for γ-ray lines copiously emitted in the ³He bombardment of ¹⁶O nuclei: the 937-, 1042-, and 1081-keV lines of ¹⁸F and the 1887-keV line of ¹⁸Ne. Four Ge detectors with BGO shielding for Compton suppression were used to measure the angular distributions of the γ rays. The excitation functions have been obtained for ³He bombarding energies from 3.7 to 36 MeV. Total cross sections are tabulated for calculations relevant to γ-ray astronomy. The importance of these lines as diagnosis for the presence and properties of accelerated ³He in solar flares is discussed in light of the measured cross sections

[en] The "1"3C("1"8O,"1"6O)"1"5C and "1"2C("1"8O,"1"6O)"1"4C reactions at 84 MeV incident energy were explored up to high excitation energy of the residual nucleus thanks to the use of the MAGNEX spectrometer to detect the ejectiles. In the region above the two-neutron separation energy, a resonance has been observed in both nuclei, attributed to the Giant Pairing Vibration (GPV). The neutron decay of the "1"5C resonances, including the GPV, populated via the two- neutron transfer reaction has been studied using an innovative technique, which couples MAGNEX with the EDEN neutron detector array. The data show that the "1"5C GPV mainly decays via two-neutron emission. (paper)

[en] A study of the yields for different reaction channels has been performed at the Catania INFN-LNS laboratory using a ¹⁸O beam on ¹³C and ¹²C targets. The ejectiles have been momentum analyzed by the MAGNEX magnetic spectrometer. The achieved mass resolution (about 1/160) has allowed to identify the reaction products corresponding to different reaction channels. The measured yields show an enhancement of two neutrons transfer channel compared to one. This result demonstrates that the (¹⁸O, ¹⁶O) reaction proceeds mainly by the direct transfer of the neutron pair, with small contributions from second order processes.

[en] Inelastic scattering of ⁴⁰Ca on ⁴⁰Ca at 50 MeV/A has been measured in coincidence with protons at the GANIL facility. The SPEG spectrometer was associated with 240 CsI(Tl) scintillators of the INDRA 4π array, allowing for the measurement of complete decay events. The missing energy method was applied to these events. For events with excitation energy between 42 and 55 MeV, a direct decay branch by three protons towards the low energy states of ³⁷Cl gives the first evidence for a 3-phonon state built with giant resonances