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Alpha particle energy distributions in the 6He+120Sn collision have been measured at 7 bombarding energies above the Coulomb barrier. A phenomenological analysis of the centroids of the experimental distributions was performed and compared with the expected alpha-particle energies from breakup and neutron transfer reactions. Q-optimum conditions were determined using the Brinks formula for the di-neutron transfer reaction. A comparison of the measured alpha-particle production cross-sections with Continuum Discretized Coupled Channels (CDCC) calculations for breakup is presented. Fundacao de Amparo `a Pesquisa no Estado de Sao Paulo 2013/22100-7, 2014/19666-1 Conselho Nacional de Desenvolvimento Cientıfico e Tecnologico 308935/2018-7 Ministerio de Economía y Competitividad FIS2017-88410-P European Union 654002

Multiple alpha coincidence and correlations are studied in the reaction $^{12}$C+$^{12}$C at 95 MeV for fusion-evaporation events completely detected in charge. Two specific channels with Carbon and Oxygen residues in coincidence with $\alpha$-particles are addressed, which are associated with anomalously high branching ratios with respect the predictions by Hauser-Feshbach calculations. Triple alpha emission appears kinematically compatible with a sequential emission from a highly excited Mg. The phase space distribution of $\alpha$-$\alpha$ coincidences suggests a correlated emission from a Mg compound, leaving an Oxygen residue excited above the threshold for neutron decay. These observations indicate a preferential $\alpha$ emission of $^{24}$Mg at excitation energies well above the threshold for $6-\alpha$ decay., Comment: 21 pages, 17 figures, second paper of a series of two

The $^{12}$C+$^{12}$C reaction at 95 MeV has been studied through the complete charge identification of its products by means of the GARFIELD+RCo experimental set-up at INFN Laboratori Nazionali di Legnaro (LNL). In this paper, the first of a series of two, a comparison to a dedicated Hauser-Feshbach calculation allows to select a set of dissipative events which corresponds, to a large extent, to the statistical evaporation of highly excited $^{24}$Mg. Information on the isotopic distribution of the evaporation residues in coincidence with their complete evaporation chain is also extracted. The set of data puts strong constraints on the behaviour of the level density of light nuclei above the threshold for particle emission. In particular, a fast increase of the level density parameter with excitation energy is supported by the data. Residual deviations from a statistical behaviour are seen in two specific channels, and tentatively associated with a contamination from direct reactions and/or $\alpha$-clustering effects. These channels are studied in further details in the second paper of the series., Comment: 24 pages, 15 figures, first paper of a series of two

The study of nuclear states built on clusters bound by valence neutrons in their molecular configurations is a field of large interest. Clustering becomes particularly important at the dripline, where weakly bound systems prevail. For light nuclei, at an excitation energy close to the particle separation value, there are experimental evidences of such structure effects, but this is still not the case for heavier nuclear systems. Several theoretical efforts have been done in the development of pre-formation alpha-clustering models, but there is still a lack of experimental data capable to give a direct feedback. The search of alpha-cluster evidences in medium-mass systems is therefore a new challenge which can give new hints in this field of research. In the past we have studied the reactions 250, 192 and 130 MeV O-16 + Sn-116, observing a significant increase in the fast emitted alpha-particle yield. This effect was ascribed to the presence of pre-formed alpha-clusters in the 16O projectile nucleus. To further investigate these aspects in a model independent way, a new experimental campaign has been performed with the GARFIELD + RCo set up. Two different reaction entrance channels (O-16 and F-19) at the same beam velocity (16AMeV) have been measured, leading to the same Rb-81* compound nucleus. In this contribution we report on the preliminary light-charged particles emission spectra obtained in coincidence with evaporation residues and their comparison with the results obtained from a Hybrid Exciton Model calculation.

The detection of the 1809 keV emission line associated with the decay of 26 Al in the interstellar medium provides a direct evidence of recent nucleosynthesis events in our galaxy. 26 Al is thought to be mainly produced in massive stars, but in order to have a quantita- tive understanding of the 26 Al distribution, the cross section of all the nuclear reactions involved in its production should be accurately known. A recent sensitivity study demonstrated that the 25 Mg( ,n) 28 Si is the reaction with the strongest impact on the synthesis of 26 Al during explosive Neon and Carbon burning (4). In order to improve the experimental knowledge of the 25 Mg( ,n) 28 Si cross section, a new direct measurement has been performed at Legnaro National Laboratories. The experimental setup, the data analysis and preliminary results are discussed.