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The linear electromagnetic interaction between innovative hybrid metallo-dielectric nanostructured targets and laser in visible and IR range is investigated through numerical simulations. The obtained results rely on the optimization of a target based on metallic nanowires (NWs) to enhance light absorption in the visible range of the electromagnetic spectrum. The NWs are grown within the ordered nanoholes of an alumina substrate, thus, forming a plasmonic lattice with triangular symmetry. The remaining volume of the nanoholes on top of the NWs is sealed with a transparent layer of aluminum oxide that is suitable to be chemically modified for containing about 25% of deuterium atoms. The study presented here is carried out within the framework of a scientific program named PLANETA (Plasmonic Laser Absorption on Nano-Engineered Targets) aiming at investigating new laser–matter interaction schemes in the ns domain and for nuclear fusion purposes, involving especially the D–D reaction. [ABSTRACT FROM AUTHOR]

Binary collisions of either stable or radioactive heavy ions at Fermi energies allow to study the nuclear reaction mechanisms under dynamical conditions of non-equilibrium and the formation of transient pieces of nuclear matter of very short mean life times at sub-normal density. An important role in the evolutionary phase of the collision is played by the gradient of the nuclear density affecting the isospin asymmetry of the reaction products by typical transport phenomena such as the isospin diffusion and drift. Experimental determination of the value of the nuclear matter density in the early phase of the collision is a crucial step towards understanding the underlying mechanism responsible for the production of clusters. In this paper a method for evaluating the nuclear density in semi-peripheral collisions in the reaction 124 S n + 64 N i at 35 MeV/nucleon as studied with the CHIMERA multi-particle detector is described. [ABSTRACT FROM AUTHOR]

The emission probability of Intermediate Mass Fragments (IMFs) in non-central reactions has been investigated in collisions of heavy 124 Xe projectiles with the two different medium-mass targets of 64 Ni and 64 Zn at the laboratory energy of 35 A MeV. The two colliding systems differ only for the target atomic number Z and, consequently, for the isospin N/Z ratio. The probability of IMFs emission from the projectile-like fragment has been measured, showing an enhancement of the IMFs emission for the neutron rich 64 Ni target. Most of the observed projectile break-up yield is associated with the production of only one IMF, that is, a quasi-binary splitting of projectile in two fragments in a broad range of charge asymmetry. For the events with one IMF, the relative contributions of the dynamical and statistical emissions have been evaluated. We find an enhancement of dynamical break-up probability for the neutron rich target with respect to the neutron poor one. The analysis suggests influence of the target isospin in inducing the dynamical break-up of projectile-like fragments. The new data have been also compared with previous published results of 112 , 124 Sn + 58 , 64 Ni systems, in order to disentangle between isospin effects against system-size effects on the emission probability. The comparisons between previous and new data suggest that the dynamical break-up is determined by the N/Z content of both projectile and target; for the cases here investigated, the influence of the system size on the dynamical emission probability can be excluded. [ABSTRACT FROM AUTHOR]

The possible existence of cluster structures in 16C has been investigated by inspecting their breakup (induced on CH2 targets) in 10Be+6He events. The excitation energy of the projectile nucleus prior to decay is obtained via an invariant mass analysis of identified fragments. The experiment has been carried out at the FRIBs facility of INFN-LNS, by using a fragmentation cocktail beam at intermediate energies (≈ 55 MeV/nucleon) and the CHIMERA 4π multi-detector. A non-vanishing yield in the 10Be+6He correlations is reported at an excitation energy of about 20.5 MeV in 16C, in analogy with previous works. To improve these results, we recently performed a new experiment by coupling CHIMERA and FARCOS at forward angles. Preliminary details of the new experiment are reported in the text. [ABSTRACT FROM AUTHOR]

Symmetric and asymmetric aligned breakup of projectile-like fragments in 197Au + 197Au collisions at 23AMeV was studied. Independently of the asymmetry, the reaction yields have been found peaked at a common, very narrow range of impact parameters. [ABSTRACT FROM AUTHOR]

According to the model predictions, observation of toroidal objects is expected in collisions of heavy ion at low incident energies. Comparison between experimental data and model predictions which may indicate the formation of flat/toroidal nuclear systems is shown. [ABSTRACT FROM AUTHOR]

An experimental campaign aiming to investigate the effects of innovative nanostructured targets based on Ag nanowires on laser energy absorption in the ns time domain has been carried out at the Laser Energy for Nuclear Science laboratory of INFN-LNS in Catania. The tested targets were realized at INFN-Bologna by anodizing aluminium sheets in order to obtain layers of porous Al2O3 of different thicknesses, on which nanowires of various metals are grown by electro-deposition with different heights. Targets were then irradiated by using a Nd:YAG laser at different pumping energies. Advanced diagnostic tools were used for characterizing the plasma plume and ion production. As compared with targets of pure Al, a huge enhancement (of almost two order of magnitude) of the X-ray flux emitted by the plasma has been observed when using the nanostructured targets, with a corresponding decrease of the "optical range" signal, pointing out that the energetic content of the laser produced plasma was remarkably increased. This analysis was furthermore confirmed from time-of-flight spectra. [ABSTRACT FROM AUTHOR]

Isospin dependence of dynamical and thermodynamical properties observed in reactions Ca+ Ca and Ca + Ti at 25 MeV/nucleon has been studied. We used the CHIMERA multi-detector array. Strong isospin effects are seen in the isotopic distributions of light nuclei and in the competition between different reaction mechanisms in semi-central collisions. We will show also preliminary results obtained in nuclear collision Ca + Ca at 25MeV/nucleon, having very high N/Z value in the entrance channel ( N/Z = 1.4). The enhancement of evaporation residue production confirms the strong role played by the N/Z degree of freedom in nuclear dynamics. [ABSTRACT FROM AUTHOR]

We discuss results on the emission of light clusters in nuclear reactions 40Ca + 40,48Ca,46Ti at 25 MeV/nucleon. They were detected and identified in mass and charge by means of the CHIMERA 4π array. Inclusive emission at forward angles shows that isotopic yields of Li and Be nuclei are related to the N/Z values of entrance channels. Moreover, structure effects and even-odd staggering in charge distributions of intermediate mass fragments emitted at forward angles will be shown. In agreement with previous experimental findings, odd-even effects are clearly visible in N ≈ Z systems, while are less pronounced in the neutron rich collision 40Ca+48Ca. These experimental findings are compared to preliminary data obtained in 40Ca+48Ca. collision at 25 MeV/nucleon. [ABSTRACT FROM AUTHOR]

Isospin effects on dynamics of semi-central collisions involving 40Ca+40Ca, 40Ca+48Ca and 48Ca+48Ca reactions at 25 MeV/nucleon have been investigated. For the selected class of events, the balance between the emission of evaporation residues and the presence of binary-like phenomena seems to be influenced by the neutron to proton ratio (N/Z) of entrance channels. In particular, for neutron-rich systems, evaporation residue emission is enhanced. Experimental observations confirm the key role played by the N/Z degree of freedom on nuclear dynamics at 25 MeV/nucleon. [ABSTRACT FROM AUTHOR]

Collisions involving 112Sn and 124Sn nuclei have been calculated with the ImQMD transport model in order to place constraints on the density dependences of the nuclear symmetry energy. Consistent constraints on the symmetry energy at sub-saturation density have been obtained by comparing these transport calculations to measurements of isospin diffusion and to the ratios of neutron and proton spectra. New isospin diffusion results from E/A = 35 MeV are also presented. [ABSTRACT FROM AUTHOR]

Various aspects observed in the reactions 40Ca+40,48 Ca,46Ti at E=25 MeV/nucleon, studied by means of the CHIMERA detector, will be discussed. An isospin effect on the competition between heavy residue production and binary-like channels has been observed in incomplete fusion events. From the thermodynamical point of view, kinetic energy spectra of protons emitted in fusion-evaporation events were fitted with two maxwellian functions. Despite of the different neutron richness of the populated sources, the average temperatures obtained for the quasi-fused systems are similar (T≃5.2MeV). We also performed a preliminary reconstruction of the excitation energy reached by quasi-fusion sources populated in the studied reactions. [ABSTRACT FROM AUTHOR]

Intermediate energy beams of light exotic nuclei have been produced at LNS by the FRIBs facility. Thanks to these beams, a complex study of the structure of halo nuclei in the 11Be region has been started exploiting the performances of the CHIMERA array. [ABSTRACT FROM AUTHOR]

In laser-driven plasma, ion acceleration of aluminum with the production of a quasi-monoenergetic beam has occurred. A useful device to analyze the ions is the Thomson parabolas spectrometer, a well-known diagnostic that is able to obtain information on charge-to-mass ratio and energy distribution of the charged particles. At the LENS (Laser Energy for Nuclear Science) laboratory of INFN-LNS in Catania, experimental measures were carried out; the features of LENS are: Q-switched Nd:YAG laser with 2 J laser energy, 1064 nm fundamental wavelengths, and 6 ns pulse duration. [ABSTRACT FROM AUTHOR]