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The 130Te(20Ne,20O)130Xe double charge exchange reaction was measured for the first time at very forward angles with the MAGNEX magnetic spectrometer at INFN-LNS. The study, performed at beam energy of 306 MeV, is part of a systematic exploration promoted by the NUMEN project. The last aims to measure specific reaction cross sections to provide experimentally driven information about nuclear matrix elements of interest in the context of neutrinoless double beta decay.

Starting from experimental studies on alpha-clustering in excited self-conjugate nuclei (from $^{16}$O to $^{28}$Si), temperature and density conditions for such a clustering are determined. Measured temperatures have been found in the range of 5.5 - 6.0 MeV whereas density values of 0.3 - 0.4 times the saturation density are deduced, i.e., 0.046 to 0.062 $fm^{-3}$. Such a density domain is also predicted by constrained self-consistent mean field calculations. These results constitute a benchmark for alpha clustering from self-conjugate nuclei in relation to descriptions of stellar evolution and supernovae., 7 pages, 3 figures. arXiv admin note: text overlap with arXiv:1602.05827, arXiv:1603.01114

International audience; The possibility to use a special class of heavy-ion induced direct reactions, such as double charge exchange reactions, is discussed in view of their application to extract information that may be helpful to determinate the nuclear matrix elements entering in the expression of neutrinoless double beta decay half-life. The strategies adopted in the experimental campaigns performed at INFN - Laboratori Nazionali del Sud are briefly described, emphasizing the advantages of the multi-channel approach to nuclear reaction data analysis.

Double charge exchange (DCE) reactions could provide experimentally driven information about nuclear matrix elements of interest in the context of neutrinoless double-β decay. To achieve this goal, a detailed description of the reaction mechanism is mandatory. This requires the full characterization of the initial and final-state interactions, which are poorly known for many of the projectile-target systems involved in future DCE studies. Among these, we intend to study the 20Ne + 130Te and 18O + 116Sn systems at 15.3 AMeV, which are particularly relevant due to their connection with the 130Te→130Xe and 116Cd→116Sn double-β decays. We measure the elastic and inelastic scattering cross-section angular distributions and compare them with theoretical calculations performed in the optical model, one-step distorted wave Born approximation, and coupled-channel approaches using the São Paulo double-folding optical potential. A good description of the experimental data in the whole explored range of transferred momenta is obtained provided that couplings with the 21+ states of the projectile and target are explicitly included within the coupled-channel approach. These results are relevant also in the analysis of other quasi-elastic reaction channels in these systems, in which the same couplings should be included.

Background: Heavy-ion induced two-nucleon transfer reactions are powerful tools to reveal peculiar aspects of the atomic nucleus, such as pairing correlations, single-particle and collective degrees of freedom, and more. Also, these processes are in competition with the direct meson exchange in the double charge exchange reactions, which have recently attracted great interest due to their possible connection to neutrinoless double-beta decay. In this framework, the exploration of two-nucleon transfer reactions in the 20Ne+116Cd collision at energies above the Coulomb barrier is particularly relevant since the 116Cd nucleus is a candidate for the double-beta decay. Methods: We measured the excitation energy spectra and absolute cross sections for the two reactions using the MAGNEX large acceptance magnetic spectrometer to detect the ejectiles. We performed direct coupled reaction channels and sequential distorted wave Born approximation calculations using the double folding S\~ao Paulo potential to model the initial and final state interactions. The spectroscopic amplitudes for two- and singleparticle transitions were derived by different nuclear structure approaches: microscopic large-scale shell model, interacting boson model-2 and quasiparticle random phase approximation. Results: The calculations are able to reproduce the experimental cross sections for both two-neutron and twoproton transfer reactions. The role of couplings with the inelastic channels are found to be important in the two-proton transfer case. A competition between the direct and the sequential process is found in the reaction mechanism. For the two-proton transfer case, the inclusion of the 1g7/2 and 2d5/2 orbitals in the model space is crucial.

We present results of barrier distribution measurements for $^{24}\mathrm{Mg}+^{90,92}\mathrm{Zr}$ systems by the backscattering method. The measurements were done at near-barrier beam energies of 68--88.5 MeV (in the laboratory frame) at six angles. A strong discrepancy between experimental results and the predictions of the standard coupled channels calculations was observed. To test the hypothesis that this discrepancy may be due to partial energy dissipation caused by coupling to many target noncollective levels, we performed calculations using the coupled channels plus random matrix theory ($\mathrm{CC}+\mathrm{RMT}$) model. The comparison of calculations with experimental results gives qualitative support of the hypothesis; however, quantitatively the agreement is not as good as in the case of the $^{20}\mathrm{Ne}$ projectile.

It is discussed the dynamics of Isospin equilibration in reactions involving the production of Intermediate Mass Fragment (IMF) in the mid-rapidity region. The investigation proceeds through the measurements of the reduced value of the total dipolar signal obtained from the measured velocities and charges of all fragments produced in the collision 48 Ca +27 Al at 40 MeV/nucleon. Preliminary experimental results, along with the comparison with CoMD-III model calculations for different density functionals related to the symmetry energy, are presented.

International audience; The emission probability of Intermediate Mass Fragments (IMFs) in non-central reactions has been investigated in collisions of heavy $^{124}\hbox {Xe}$ projectiles with the two different medium-mass targets of $^{64}\hbox {Ni}$ and $^{64}\hbox {Zn}$ 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 $^{64}\hbox {Ni}$ 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 $^{112,124}\hbox {Sn}$ + $^{58,64}\hbox {Ni}$ 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.

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 $$^{124}Sn + ^{64}Ni$$ at 35 MeV/nucleon as studied with the CHIMERA multi-particle detector is described.

Silicon Carbide (SiC) is a relatively new entry in the world of solid-state detectors. Although SiC response to neutrons is more complex than the one obtained with diamonds, the measured energy resolution (FWHM/ E d 4 % ) makes SiC an interesting alternative to diamond and silicon detectors for fast neutrons. The results obtained from the measurements of the response of a 100 μ m thick SiC detector to neutrons in the energy range between 3 and 20 MeV at the n_TOF spallation source at CERN are presented in this paper. By selecting the neutron energy by means of the time of flight, the detector response to quasi-mono-energetic neutrons was measured. The main neutron-induced nuclear reactions were identified in the measured pulse height spectrum. Detection efficiency as a function of neutron energy was measured and interpreted based on available neutron cross section and by making use of Monte Carlo simulations.

With the advent of the new radioactive beam facilities it is necessary to develop neutron detection systems integrated with charged particle ones. The integration of the neutron signal, especially in using neutron rich beams, becomes a mandatory requirement in order to study the property of the nuclear matter in extreme conditions. For this reason new detectors using new materials have to be built. In this contribution, some new results about the efficiency estimation and the cross talk problem studied through GEANT4 simulations, related to the NArCoS project, will be described with the aim to design a new detector of both good energy and angular resolution. The detection of neutrons and charged particles in the same elementary detection cell is envisaged.

We describe the use of the 4tt CHIMERA charged particle detector as a large efficiency y-ray detector. The CsI(Tl) stage of the CHIMERA telescope is used to detect and identify y-rays. The high detection efficiency and the sufficient energy resolution guaranteed by CsI(Tl) allows us to use the detector for the study of rare decays. Two examples are reported: the low probability gamma decay (68Ni; the measurement of the gamma decay probability of excited levels of 12C as the Hoyle state at 7.65 (∼10−4) MeV and the 3- level at 9.64 MeV (∼107), both important for the Carbon production in stars. Future experiments made possible at INFN-LNS by the availability of the new fragment separator FRAISE are also outlined.

A dedicated laboratory at Laboratori Nazionali del Sud (LNS) of Catania was realized with the aim to investigate nuclear reactions of astrophysical interest in plasma environment. In this contribution, the facility LENS (Laser Energy for Nuclear Science), useful to study laser- produced plasmas, will be described and some results will be presented.

The motivation of the present paper is to study the performance of EJ 299-33 scintillator in online and off-line analysis in high rate scattering for nuclear reaction experiments performed with heavy ions. An experiment was carried out inside the CHIMERA chamber using 24Mg beams at 71.5 MeV and 81 MeV impinging on 92ZrO2 target. The plastic scintillator was backed by a photomultiplier tube and the anode pulses were digitized through 100 MHz GET electronics for the purpose of pulse shape discrimination (PSD) studies. Performances of the plastic scintillator have been tested with respect to PSD capabilities and energy spectra analysis under beam irradiations in a high background environment.

Background: Double charge exchange (DCE) nuclear reactions have recently attracted much interest as tools to provide experimentally driven information about nuclear matrix elements of interest in the context of neutrinoless double-β decay. In this framework, a good description of the reaction mechanism and a complete knowledge of the initial and final-state interactions are mandatory. Presently, not enough is known about the details of the optical potentials and nuclear response to isospin operators for many of the projectile-target systems proposed for future DCE studies. Among these, the Ne20+Ge76 DCE reaction is particularly relevant due to its connection with Ge76 double-β decay. Purpose: We intend to characterize the initial-state interaction for the Ne20+Ge76 reactions at 306 MeV bombarding energy and determine the optical potential and the role of the couplings between elastic channel and inelastic transitions to the first low-lying excited states. Methods: We determine the experimental elastic and inelastic scattering cross-section angular distributions, compare the theoretical predictions by adopting different models of optical potentials with the experimental data, and evaluate the coupling effect through the comparison of the distorted-wave Born approximation calculations with the coupled channels ones. Results: Optical models fail to describe the elastic angular distribution above the grazing angle (≈9.4∘). A correction in the geometry to effectively account for deformation of the involved nuclear systems improves the agreement up to about 14∘. Coupled channels effects are crucial to obtain good agreement at large angles in the elastic scattering cross section. Conclusions: The analysis of elastic and inelastic scattering data turned out to be a powerful tool to explore the initial and final-state interactions in heavy-ion nuclear reactions at high transferred momenta.

International audience; Background: Near-threshold α-clustered states in light nuclei have been postulated to have a structure consisting of a diffuse gas of α particles which condense into the 0s orbital. Experimental evidence for such a dramatic phase change in the structure of the nucleus has not yet been observed. Purpose: To understand the role of α condensation in light nuclei experimentally. Method: To examine signatures of this α condensation, a compound nucleus reaction using 160-, 280-, and 400-MeV O16 beams impinging on a carbon target was used to investigate the C12(O16,7α) reaction. This permits a search for near-threshold states in the α-conjugate nuclei up to Mg24. Results: Events up to an α-particle multiplicity of seven were measured and the results were compared to both an extended Hauser-Feshbach calculation and the Fermi breakup model. The measured multiplicity distribution exceeded that predicted from a sequential decay mechanism and had a better agreement with the multiparticle Fermi breakup model. Examination of how these 7α final states could be reconstructed to form Be8 and C12(02+) showed a quantitative difference in which decay modes were dominant compared to the Fermi breakup model. No new states were observed in O16, Ne20, and Mg24 due to the effect of the N-α penetrability suppressing the total α-particle dissociation decay mode. Conclusion: The reaction mechanism for a high-energy compound nucleus reaction can only be described by a hybrid of sequential decay and multiparticle breakup. Highly α-clustered states were seen which did not originate from simple binary reaction processes. Direct investigations of near-threshold states in N-α systems are inherently impeded by the Coulomb barrier prohibiting the observation of states in the N-α decay channel. No evidence of a highly clustered 15.1-MeV state in O16 was observed from [Si★28,C12(02+)]O16(06+) when reconstructing the Hoyle state from three α particles. Therefore, no experimental signatures for α condensation were observed.

Main features of fragments produced in 58Ni+40Ca and 58Ni+48Ca systems at 25 AMeV, collected by Chimera multidetector at INFN Laboratori Nazionali del Sud (Italy), are analysed in order to study properties of moderately excited systems (Ex=2-5 AMeV) formed in central collisions. By means of correlations between specific global variables, sensitive to the centrality of the collision, a stringent selection of Fusion-Evaporation residues, Multifragmentation sources and their decay products has been performed. The influence of the isospin contents of the systems on the reaction mechanism is carefully investigated and relevant observables such as isospin asymmetry N/Z or charge and mass of fragments, are discussed in order to probe the fragmentation path, characterised by short living ( ∼ 100fm/c) low density states of nuclear matter out of equilibrium. Preliminary comparisons with predictions of the BLOB model, in a semi-classical mean field framework, are presented, investigating cluster production emerging from the occurrence of low-density instabilities in central collisions.

The 0 2 + Hoyle state and few other excited levels of 12C are fundamental for the production of carbon in the universe. In particular, the γ decay branching ratio is of utmost importance, being the only way to produce a carbon at the ground state. For the purpose to precisely investigate the decay mechanism of such states we conducted an experiment, at Laboratori Nazionali del Sud-Istituto Nazionale di Fisica Nucleare (INFN-LNS), using the reaction α + 12 C at 64 MeV. We used the 4π CHIMERA detector to detect both α and γ 12 C decay channels. Details of the experiment and preliminary results are discussed in the paper.

An updated overview of recent results on Heavy-Ion induced reactions of interest for neutrinoless double beta decay is reported in the framework of the NUMEN project. The NUMEN idea is to study heavy-ion induced Double Charge Exchange (DCE) reactions with the aim to get information on the nuclear matrix elements for neutrinoless double beta (0νββ) decay. Moreover, to infer the neutrino average masses from the possible measurement of the half- life of 0νββ decay, the knowledge of the nuclear matrix elements is a crucial aspect. Uma visão geral atualizada dos resultados recentes sobre reações induzidas por íons pesados ​​de interesse para o decaimento beta duplo sem neutrinos é relatada na estrutura do projeto NUMEN. A ideia do NUMEN é estudar reações de Double Charge Exchange (DCE) induzidas por íons pesados ​​com o objetivo de obter informações sobre os elementos da matriz nuclear para o decaimento beta duplo sem neutrinos (0νββ). Além disso, para inferir as massas médias dos neutrinos a partir da possível medição da meia-vida do decaimento 0νββ, o conhecimento dos elementos da matriz nuclear é um aspecto crucial. 1308 012002

Time resolved characterization of plasma X-ray emission represents an innovative technique to characterize non-equilibrium phases in Electron Cyclotron Resonance Ion Sources (ECRIS). Indeed, although ECRIS plasmas are usually in dynamical equilibrium, many relevant phenomena are characterized by fast transients and require a dedicated diagnostics to be fully investigated. In particular, time resolved diagnostics can be applied to characterize the X ray emission during the plasma turn on and off and during the turbulence phenomena induced by Cyclotron-Maser instability. This paper presents the experimental set-up used during the last campaign at measurement carried out at the IstitutoNazionale FisicaNucleare-LaboratoriNazionali del Sud (INFN-LNS), together with the main achieved results. Particular relevance will be given to the characterization of the afterglow phase, which highlighted the existence of two electron populations characterized by different mean lifetime. Evidences of X-ray bursts emission in the afterglow phase, compatible with Cyclotron Maser instability, will be also shown. c 2019 IOP Publishing Ltd and Sissa Medialab.

International audience; In heavy ion collisions at low energy (E/A < 10–15 MeV/nucleon) the N/Z ratio in the entrance channel is closely related to the isospin degree of freedom and can influence the reaction mechanisms and consequently the production of the fragments in the exit channel. We analyse the fragment production cross sections in the reactions$^{86}$Kr +$^{48}$Ca and$^{78}$Kr +$^{40}$Ca , at the laboratory energy of 10 MeV/nucleon. The experiment was conducted at the INFN Laboratori Nazionali del Sud in Catania, by using the $ 4\pi$ detector CHIMERA. For the two reactions, elastic scattering measurements are performed to extract the normalization factor used to evaluate the absolute cross sections. Velocity and energy spectra, mass and charge distributions, as well as dynamic features of reaction products, are studied. The study of the characteristics of mass and charge distributions, energy and velocity spectra of the reaction products shows mainly a relaxed component, related to fusion reaction followed by evaporation or binary decay. Nevertheless signals ascribable to a non equilibrated component are present. Structure effects are evident in the staggered shape of emitted fragments cross sections and are more pronounced in the neutron poor system. The analysis highlights clear differences for the two systems in the contributions arising from different reaction mechanisms. Besides, a study of the overall influence from the entrance channel energy is performed. Comparisons to DNS (DiNuclear System) and GEMINI++ models are reported. The data analysis indicates a slightly higher fusion-evaporation cross section and a strongly pronounced probability of fission-like processes for the neutron poor system with respect to the neutron rich one. The neutron enrichment seems thus to limit the formation of the composite system and to inhibit the fission decay channel.

In this work we present the response of a new large volume 4H Silicon Carbide (SiC) detector to 14 MeV neutrons. The device has an active thickness of 100 μ m (obtained by epitaxial growing) and an active area of 25 mm2. Tests were conducted at the ENEA-Frascati Neutron Generator facility by using 14.1 MeV neutrons. The SiC detector performance was compared to that of Single-Crystal Diamond (SCD) detectors. The SiC response function was successfully measured and revealed a very complex structure due to the presence in the detector of both Silicon and Carbon atoms. Nevertheless, the flexibility in the SiC manufacturing and the new achievements in terms of relatively large areas (up 1x1 cm2) and a wide range of thicknesses makes them an interesting alternative to diamond detectors in environments where limited space and high neutron fluxes are an issue, i.e. modern neutron cameras or in-vessel tokamak measurements for the new generation fusion machines such as ITER. The absence of instabilities during neutron irradiation and the capability to withstand high neutron fluences and to follow the neutron yield suggest a straightforward use of these detectors as a neutron diagnostics.

International audience; NUMEN aims at accessing experimentally driven information on Nuclear Matrix Elements (NME) involved in the half-life of the neutrinoless double beta decay (0νββ), by high-accuracy measurements of the cross sections of Heavy Ion (HI) induced Double Charge Exchange (DCE) reactions. First evidence about the possibility to get quantitative information about NME from experiments is found for the (^18O,^18Ne) and (^20Ne,^20O) reactions. Moreover, to infer the neutrino average masses from the possible measurement of the half-life of 0νββ decay, the knowledge of the NME is a crucial aspect. The key tools for this project are the high resolution Superconducting Cyclotron beams and the MAGNEX magnetic spectrometer at INFN Laboratori Nazionali del Sud in Catania (Italy). The measured cross sections are extremely low, limiting the present exploration to few selected isotopes of interest in the context of typically low-yield experimental runs. A major upgrade of the LNS facility is foreseen in order to increase the experimental yield of at least two orders of magnitude, thus making feasible a systematic study of all the cases of interest.

The MAGNEX magnetic spectrometer is used in the experimental measurements of Double Charge Exchange and Multi-Nucleon Transfer reactions induced by heavy ions within the NUMEN project. These processes are characterized by small cross sections under a large background due to other reaction channels. Therefore an accurate control of the signal to background ratio is mandatory. In this article, the determination of the MAGNEX spectrometer background contribution on cross section measurements is presented by applying a suitable analysis to quantify the limits of the adopted particle identification technique. The method is discussed considering the 116Cd(20Ne, 20O)116Sn Double Charge Exchange reaction data, however it can be applied to any other reaction channel of interest.

International audience; The article describes the main achievements of the NUMEN project together with an updated and detailed overview of the related R&D activities and theoretical developments. NUMEN proposes an innovative technique to access the nuclear matrix elements entering the expression of the lifetime of the double beta decay by cross section measurements of heavy-ion induced Double Charge Exchange (DCE) reactions. Despite the fact that the two processes, namely neutrinoless double beta decay and DCE reactions, are triggered by the weak and strong interaction respectively, important analogies are suggested. The basic point is the coincidence of the initial and final state many-body wave functions in the two types of processes and the formal similarity of the transition operators. First experimental results obtained at the INFN-LNS laboratory for the$^{40}$Ca($^{18}$O,$^{18}$Ne)$^{40}$Ar reaction at 270MeV give an encouraging indication on the capability of the proposed technique to access relevant quantitative information. The main experimental tools for this project are the K800 Superconducting Cyclotron and MAGNEX spectrometer. The former is used for the acceleration of the required high resolution and low emittance heavy-ion beams and the latter is the large acceptance magnetic spectrometer for the detection of the ejectiles. The use of the high-order trajectory reconstruction technique, implemented in MAGNEX, allows to reach the experimental resolution and sensitivity required for the accurate measurement of the DCE cross sections at forward angles. However, the tiny values of such cross sections and the resolution requirements demand beam intensities much larger than those manageable with the present facility. The on-going upgrade of the INFN-LNS facilities in this perspective is part of the NUMEN project and will be discussed in the article.

The FARCOS (Femtoscope ARray for Correlation and Spectroscopy) collaboration is finally going to instrument the first batch of 10-12 telescopes. They are capable of reconstructing the particle’s momentum with a high degree of precision and of performing correlation measurements of Light Charged Particles (LCPs) and of LCPs and Intermediate Mass Fragments thanks to the very good energy and angular and resolution. Each telescope features a sensitive area of 6.4 × 6.4 cm2 and is composed of three detection stages: two Si layers and a CsI(Tl) calorimeter. The FARCOS cluster modularity allows the arrangement in different configurations, depending on the physics case one wants to address. The final system will be a modular assembly of 20 telescopes. The total number of readout channels for the final FARCOS system is 2560 channels for the silicon layers and 80 channels for the scintillators. In this paper, we focus on the FARCOS basic module and system architecture and illustrate its performance as assessed in test beams in true experimental conditions.

It is known that the low-energy E1 strength, known as the Pygmy Dipole Resonance (PDR), can be excited by both isovector and isoscalar probes. In this work, we report on the results of an experiment, carried out at the LNS-INFN in Catania, with the aim to study the Pygmy Dipole Resonance induced in the 68Ni nucleus through the interaction with a 12C isoscalar target. The CHIMERA multidetector and the FARCOS array were used to detect, respectively, γ rays and charged particles. Details on the experimental set-up, data analysis and results are reported.

International audience; Preliminary analysis of the Hoyle-Gamma experiment is presented, where simultaneous gamma-particles detection for the α + 12C → α + (12C* + γ) reaction is used to suppress the background various orders of magnitude. This will allow us to measure very small Γ partial widths of 12C. Details of the method, the implementation and CHIMERA software analysis are presented as well as preliminary results.

International audience; The study of cluster states in neutron-rich Be and C isotopes is a subject of interest in Nuclear Physics. These states should be characterized by high deformation where α-clusters are bounded by valence neutrons. We performed a spectroscopic study of 10Be and 16C isotopes via projectile break-up reactions, by using radioactive beams produced at the INFN-LNS FRIBs facility and the Chimera 4π array. The possible evidence of a new 10Be state at 13.5 MeV excitation energy was found in the 6He+4He disintegration channel. The spectroscopy of 16C was studied via the 6He+10Be break-up channel; in this case we found the indication of a possible new state at about 20.6 MeV.

International audience; A study of different post-stripper materials for the (20Ne, 20O) double charge exchange and (20Ne, 20F) single charge exchange reactions at zero degrees using the MAGNEX spectrometer at 22 and 15 AMeV is presented. All these experiments belongs to the experimental campaign planned in the NUMEN project (NUclear Matrix Elements for Neutrinoless double beta decay).

In nuclear reactions at Fermi energies two and multi particles intensity interferometry correlation methods are powerful tools in order to pin down the characteristic time scale of the emission processes. In this paper we summarize an improved application of the fragment-fragment correlation function in the specific physics case of heavy projectile-like (PLF) binary massive splitting in two fragments of intermediate mass(IMF). Results are shown for the reverse kinematics reaction 124 Sn+64 Ni at 35 AMeV that has been investigated by using the forward part of CHIMERA multi-detector. The analysis was performed as a function of the charge asymmetry of the observed couples of IMF. We show a coexistence of dynamical and statistical components as a function of the charge asymmetry. Transport CoMD simulations are compared with the data in order to pin down the timescale of the fragments production and the relevant ingredients of the in medium effective interaction used in the transport calculations.

International audience; The NUMEN project proposes to study heavy-ion induced Double Charge Exchange (DCE) reactions with the final goal to get information on the nuclear matrix elements for neutrinoless double beta (0νββ) decay. The knowledge of the nuclear matrix elements is crucial to infer the neutrino average masses from the possible measurement of the half-life of 0νββ decay. DCE reactions and 0νββ decay present some similarities, the initial and final-state wave functions are the same and the transition operators are similar. The experimental measurements of DCE reactions induced by heavy ions present a number of challenging aspects, since they are characterized by very low cross sections.

The present study has been carried out in order to investigate about the possibility of using EJ 299-33 scintillator in a multi-detector array to detect neutrons along with light charged particles. In a reaction induced by stable and exotic heavy-ions beams, where copious production of neutrons and other light charged particles occurs, discrimination with low identification threshold of these particles are of great importance. In view of this, EJ 299-33 scintillator having dimension of 3 cm × 3 cm × 3 cm backed by a photomultiplier tube was tested and used under vacuum to detect neutrons, gamma-rays and alpha particles emitted by radioactive sources. Anode pulses from the photomultiplier tube were digitized through GET electronics, recorded and stored in a data acquisition system for the purpose of an off-line analysis. The measurements, under vacuum and low background conditions, show good pulse shape discrimination properties characterized by low identification threshold for neutrons, gamma-rays and alpha particles. The Figures of Merit for neutron-gamma and alpha particles-gamma discriminations have been evaluated together with the energy resolution for gamma-ray and alpha particles.

In this paper we briefly discuss about a novel application of the IMF- IMF correlation function in the physics case of heavy projectile-like (PLF) binary fission-like massive splitting in heavy ion collisions at Fermi energy. In particular, results are shown for the reverse kinematics reaction 124Sn+64Ni at 35 AMeV that has been investigated by using the forward part of CHIMERA multi-detector. Transport CoMD simulations are compared with the data. The main analysis was performed as a function of the charge asymmetry of the decay channel. The coexistence of dynamical and statistical components as a function of the charge asymmetry of the binary breakup is clearly evidenced. We show that the IMF-IMF correlation functions, when coupled with transport calculations, can be used to pin down the timescale of the fragments production and consequently the relevant ingredients of the in medium effective interaction. Efforts are being planned to extend the method to different reaction mechanisms and nuclear systems and, also, to compare the data with different transport theory simulations.

International audience; At Laboratori Nazionali del Sud of Catania an experiment has been carried out in order to investigate the correlations between particles produced in 12C+24Mg reaction at 35 AMeV incident energy. Two α correlation has been explored because provide information about temperature of 8Be nuclei produced in the reaction, while three α correaltion has been studied in order to evaluate the competition between sequential and direct decay mode of resonances produced in 12C quasi-projectiles.

International audience; The current work is a part of the NUMEN project, which aims to deduce the nuclear matrix elements (NME) of neutrinoless double beta decay by measuring the cross sections in heavy-ion induced Double Charge Exchange (DCE) reactions. The particle identification for the competing transfer reaction channels has been studied for the 18O + 116Sn system at 270 MeV.

International audience; Within the NUMEN project, we present experimental issues and data reduction for the 116Cd(20Ne,20F)116In single charge exchange, 116Cd(20Ne,18O)118In two-proton transfer and 116Cd(20Ne,19F)117In one-proton transfer reactions at 15 AMeV incident energy.

International audience; In heavy-ion collisions at low energy, the decay mode of the compound nucleus formed in fusion reactions can be strongly influenced by the isospin degree of freedom, strictly connected to the isotopic ratio N/Z of the system. The competition among the disintegration modes of 118,134Ba∗ produced in 78,86Kr+40,48Ca reactions at 10 A MeV has been studied in the framework of the ISODEC experiment, and experimental data have been compared with the prediction of GEMINI++ and DiNuclear System (DNS) models.

The NUMEN project aims at accessing experimentally driven information on Nuclear Matrix Elements (NME) involved in the half-life of the neutrinoless double beta decay (0νββ), by high-accuracy measurements of Heavy Ion (HI) induced Double Charge Exchange (DCE) reaction cross sections. In particular, the (18O,18Ne) and (20Ne,20O) reactions are used as tools for β+β+ and β−β− decays, respectively. In the experiments, performed at INFN - Laboratory Nazionali del Sud (LNS) in Catania, the beams are accelerated by the Superconducting Cyclotron (CS) and the reaction ejectiles are detected the MAGNEX magnetic spectrometer. The measured cross sections are challengingly low (a few nb), being the total reaction cross section much larger (a few b), thus a high sensitivity and a large rejection capability are demanded to the experimental set-up. This limits the present exploration to few selected isotopes of interest in the context of typically low-yield experimental runs. A major upgrade of the LNS facility is foreseen in order to increase the experimental yield of at least two orders of magnitude, still keeping the high sensitivity of the present set-up, making it feasible a systematic study of all the cases of interest. Frontiers technologies are going to be developed, to this purpose, for the accelerator and the detection systems. In parallel, advanced theoretical models are being developed in order to extract the nuclear structure information from the measured cross sections.

Few years ago we proposed a novel detection system textbf- named FARCOS (Femtoscopy ARray for COrrelations andSpectroscopy) – to target different open cases in nuclear physics. The basic cluster unit of the FARCOS array is a telescope structure with an active area of $6.4 \times 6.4$ cm$^{\mathbf {2}}$ composed of three detection stages. The first two detection layers are DC-coupled Double-Sided Silicon Strip Detectors (DSSSDs), 300 $\mu \textbf{m}$ thick and 1500 $\mu \textbf{m}$ thick, featuring $32 \times 32$ orthogonal strips. The third stage, acting as calorimeter, is composed of four truncated pyramids of CsI(Tl) crystals with an active area of $3.2 \times 3.2$ cm$^{\mathbf {2\, }}$textbfand an absorption length of 6 cm arranged in window configuration. The final system will be a modular assembly of 20 telescopes.A key feature of FARCOS is the identification of the particles stopping even in the first detection layer, relying on pulse shape analysis techniques. The FARCOS frontend electronics features a full scale energy range up to 2 GeV with 5 different selectable ranges and an energy resolution down to 10 keV FWHM with a power budget of about 10 mW/channel in the case of the lower full scale energy range. Its core is a custom multichannel charge preamplifier VLSI chip.The system performance has been extensively qualified on few workhorses in view of the assembly of the final telescopes foreseen for 2018.

In this paper, we present the status of the line for laser-driven light ions acceleration (L3IA) currently under implementation at the Intense Laser Irradiation Laboratory (ILIL), and we provide an overview of the pilot experimental activity on laser-driven ion acceleration carried out in support of the design of the line. A description of the main components is given, including the laser, the beam transport line, the interaction chamber, and the diagnostics. A review of the main results obtained so far during the pilot experimental activity is also reported, including details of the laser-plasma interaction and ion beam characterization. A brief description of the preliminary results of a dedicated numerical modeling is also provided.