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Albergo thermometers with double isotope, isotone, and isobar yield ratio pairs with one proton and/or neutron difference are investigated. Without any extra sequential decay correction, a real temperature value of $4.9\ifmmode\pm\else\textpm\fi{}0.5$ MeV is deduced from the yields of the experimentally reconstructed primary hot intermediate mass fragments (IMFs) from $^{64}\mathrm{Zn}+^{112}\mathrm{Sn}$ collisions at 40 MeV/nucleon using the Albergo thermometer for the first time. An experimental sequential decay correction from the apparent temperatures to the real ones for 12 other reaction systems with different neutron-proton ($N/Z$) asymmetries in the same experiment, $^{70}\mathrm{Zn}$, $^{64}\mathrm{Ni}$ on $^{112,124}\mathrm{Sn}$, $^{58,64}\mathrm{Ni}$, $^{197}\mathrm{Au}$, and $^{232}\mathrm{Th}$ at 40 MeV/nucleon, is performed using an empirical correction factor approach of Tsang et al. [Phys. Rev. Lett. 78, 3836 (1997)] with the deduced 4.9-MeV temperature value. The dependence of nuclear temperature on the source $N/Z$ asymmetry is further investigated using these deduced real source temperature values from the present 13 systems. It is found that the deduced real source temperatures at the present source $N/Z$ range show a rather weak dependence on the source $N/Z$ asymmetry. By comparison between our previous results and those from other independent experiments, a consistent description for the $N/Z$ asymmetry dependence of nuclear temperature is addressed.

The dependence of the nuclear temperature on the source neutron-proton ($N/Z$) asymmetry has been experimentally investigated with the light charged particles (LCPs) generated from 13 reaction systems with different $N/Z$ asymmetries, $^{64}\mathrm{Zn}$ on $^{112}\mathrm{Sn}$, and $^{70}\mathrm{Zn}$, $^{64}\mathrm{Ni}$ on $^{112,124}\mathrm{Sn}$, $^{58,64}\mathrm{Ni}$, $^{197}\mathrm{Au}$, and $^{232}\mathrm{Th}$ at 40 MeV/u. A rather weak $N/Z$ asymmetry dependence of the source temperature has been qualitatively inferred from the extracted $N/Z$ asymmetry dependence of the apparent temperature and that of the relative temperature change by the sequential decay effects with the help of the theoretical simulations. Comparing the present result with those from our previous work and other available experimental results, a weak $N/Z$ asymmetry dependence of nuclear temperature is commonly observed in different independent experiments and with different thermometers, except for the result reported by McIntosh et al. [Phys. Lett. B 719, 337 (2013)]. The origin of the difference between the conclusion of the former group and that of McIntosh et al. is addressed, using statistical multifragmentation model (SMM) simulations.

The dependence of the nuclear temperature on the source neutron-proton ($N/Z$) asymmetry is experimentally investigated with the intermediate mass fragments (IMFs) generated from thirteen reaction systems with different $N/Z$ asymmetries, $^{64}\mathrm{Zn}$ on $^{112}\mathrm{Sn}$ and $^{70}\mathrm{Zn}, ^{64}\mathrm{Ni}$ on $^{112,124}\mathrm{Sn}, ^{58,64}\mathrm{Ni}, ^{197}\mathrm{Au}, ^{232}\mathrm{Th}$ at 40 MeV/nucleon. The apparent source temperatures for these systems are determined from the measured IMF yields from the intermediate velocity sources using eight carbon-related double isotope ratio thermometers. A rather weak $N/Z$ asymmetry dependence of the source temperature is qualitatively inferred from the extracted $N/Z$ asymmetry dependence of the apparent temperature and that of the relative temperature change by the sequential decay effects with the help of the theoretical simulations. The present result is compared with those from other available experiments.

Heavy ion collisions near the Fermi energy produce a ‘freezout’ region where fragments appear and later decay, emitting mainly neutrons, protons, alpha particles, and gamma rays. These decay products carry information about the decaying nuclei. Fragmentation events may result in high yields of boson particles, especially alpha particles, and may carry important information about the nuclear Bose Einstein condensate (BEC). We study ‘in medium’ four α correlations and link them to the ‘fission’ of 16O in two 8Be in the ground state or 12C*(Hoyle state)+α. Using novel techniques for the correlation functions, we confirm the resonance of 16O at 15.2 MeV excitation energy, and the possibility of a lower resonance, close to 14.72 MeV. The latter resonance is the result of all α particles having 92 keV relative kinetic energies.

A novel method for the production of important medical radioisotopes has been developed. The approach is based on performing the nuclear reaction in inverse kinematics, namely sending a heavy-ion beam of appropriate energy on a light target (e.g. H, d, He) and collecting the isotope of interest. In this work, as a proof-of-concept, we studied the production of the theranostic radionuclide

Symmetry energy, temperature and density at the time of the intermediate mass fragment formation are determined in a self-consistent manner, using the experimentally reconstructed primary hot isotope yields and anti-symmetrized molecular dynamics (AMD) simulations. The yields of primary hot fragments are experimentally reconstructed for multifragmentation events in the reaction system Zn 64 + Sn 112 at 40 MeV / nucleon . Using the reconstructed hot isotope yields and an improved method, based on the modified Fisher model, symmetry energy values relative to the apparent temperature, a sym / T , are extracted. The extracted values are compared with those of the AMD simulations, extracted in the same way as those for the experiment, with the Gogny interaction with three different density-dependent symmetry energy terms. The a sym / T values change according to the density-dependent symmetry energy terms used. Using this relation, the density of the fragmenting system is extracted first. Then symmetry energy and apparent temperature are determined in a self consistent manner in the AMD model simulations. Comparing the calculated a sym / T values and those of the experimental values from the reconstructed yields, ρ / ρ 0 = 0.65 ± 0.02 , a sym = 23.1 ± 0.6 MeV and T = 5.0 ± 0.4 MeV are evaluated for the fragmenting system experimentally observed in the reaction studied.

The de-excitation of alpha-conjugate nuclei produced in reactions of 35 MeV/nucleon 40Ca with 40Ca has been investigated. Particular emphasis is placed on examining the dynamics of collisions leading to projectile-like fragment exit channels. A general exploration of the reaction systematics reveals the binary dissipative character of the collisions and a hierarchy effect similar to that seen for heavier systems. Investigation of the subset of events characterized by a total alpha-conjugate mass (alpha particles plus alpha-conjugate fragments) equal to 40 and atomic number equal to 20 reveals a dominance of alpha-conjugate exit channels. The hierarchy effect for these channels leads to the production of alpha-clustered neck structures with potentially exotic geometries and properties.

Ratios of differential chemical potential values relative to the temperature, $({\ensuremath{\mu}}_{n}\ensuremath{-}{\ensuremath{\mu}}_{p})/T$, extracted from isotope yields of 13 reaction systems at 40 MeV/nucleon are compared to those of a quantum statistical model to determine the temperature and symmetry energy values of the fragmenting system. The experimental $({\ensuremath{\mu}}_{n}\ensuremath{-}{\ensuremath{\mu}}_{p})/T$ values are extracted based on the modified Fisher model. Using the density value of $\ensuremath{\rho}/{\ensuremath{\rho}}_{0}=0.56$ from the previous analysis, the temperature and symmetry energy values of $T=4.6\ifmmode\pm\else\textpm\fi{}0.4$ MeV and ${a}_{\mathrm{sym}}=23.6\ifmmode\pm\else\textpm\fi{}2.1$ MeV are extracted in a framework of a quantum statistical model. These values agree well with those of the previous work, in which a self-consistent method was utilized with antisymmetrized molecular dynamics simulations. The extracted temperature and symmetry energies are discussed together with other experimental values published in literature.

The neutron detection efficiency of a DEMON detector, averaged over the whole volume, was calculated using GEANT and applied to determine neutron multiplicities in an intermediate heavy ion reaction. When a neutron source is set at a distance of about 1 m from the front surface of the detector, the average efficiency, eav , is found to be significantly lower (20-30%) than the efficiency measured at the center of the detector, e0 . In the GEANT simulation the ratio R= eav / e0 was calculated as a function of neutron energy. The experimental central efficiency multiplied by R was then used to determine the average efficiency. The results were applied to a study of the 64 Zn+ 112 Sn reaction at 40 A MeV which employed 16 DEMON detectors. The neutron multiplicity was extracted using a moving source fit. The derived multiplicities are compared well with those determined using the neutron ball in the NIMROD detector array in a separate experiment. Both are in good agreement with multiplicities predicted by a transport model calculation using an antisymmetric molecular dynamics (AMD) model code. © 2013 Elsevier B.V.

Isoscaling is derived within a recently proposed modified Fisher model where the free energy near the critical point is described by the Landau O ( m 6 ) theory. In this model m = N f − Z f A f is the order parameter, a consequence of (one of) the symmetries of the nuclear Hamiltonian. Within this framework we show that isoscaling depends mainly on this order parameter through the ‘external (conjugate) field’ H. The external field is just given by the difference in chemical potentials of the neutrons and protons of the two sources. To distinguish from previously employed isoscaling relationships, this approach is dubbed: m-scaling. We discuss the relationship between this framework and the standard isoscaling formalism and point out some substantial differences in interpretation of experimental results which might result. These should be investigated further both theoretically and experimentally.

A technique to identify the heavy ions produced in nuclear reactions is presented. It is based on the use of a hybrid detector, which measures the energy loss, the residual energy, the position and angle of the ions at the focal plane of a magnetic spectrometer. The key point is the use of a powerful algorithm for the reconstruction of the ion trajectory, which makes the technique reliable even with large acceptance optical devices. Experimental results with the MAGNEX spectrometer show a remarkable resolution of about 1/160 in the mass parameter.

A very brief summary Of Our Current research on clustering in low density matter formed in near Fermi energy heavy ion collisions is presented. At the lowest densities and temperatures large alpha mass fractions are observed. Temperature and density dependent symmetry free energies have been derived from isoscaling analyzes of the yields of nuclei with A = 4. The symmetry free energies are far above those obtained in common effective interaction calculations, reflecting cluster formation, primarily of alpha particles, not included in such calculations.

Neutrinoless double beta decay (0v\b{eta}\b{eta}) is considered the best potential resource to access the absolute neutrino mass scale. Moreover, if observed, it will signal that neutrinos are their own anti-particles (Majorana particles). Presently, this physics case is one of the most important research "beyond Standard Model" and might guide the way towards a Grand Unified Theory of fundamental interactions. Since the 0v\b{eta}\b{eta} decay process involves nuclei, its analysis necessarily implies nuclear structure issues. In the NURE project, supported by a Starting Grant of the European Research Council (ERC), nuclear reactions of double charge-exchange (DCE) are used as a tool to extract information on the 0v\b{eta}\b{eta} Nuclear Matrix Elements. In DCE reactions and \b{eta}\b{eta} decay indeed the initial and final nuclear states are the same and the transition operators have similar structure. Thus the measurement of the DCE absolute cross-sections can give crucial information on \b{eta}\b{eta} matrix elements. In a wider view, the NUMEN international collaboration plans a major upgrade of the INFN-LNS facilities in the next years in order to increase the experimental production of nuclei of at least two orders of magnitude, thus making feasible a systematic study of all the cases of interest as candidates for 0v\b{eta}\b{eta}.

Recent data indicated a nuclear rainbow-like pattern in the elastic scattering of 16O + 27Al at $ E_{lab}=100$ MeV that arises from couplings of the ground to the low-lying states of the 27Al nucleus. Similar effect was identified in the elastic angular distribution of 16O + 12C at $ E_{lab}=281$ and 330 MeV. These experiments show a crucial role of microscopic details of nuclear structure in the elastic scattering of heavy ions at energies well above the Coulomb barrier. In this work we investigate the 16O + 27Al system at $ E_{lab}=280$ MeV for which a coupled channel calculation predicts a pronounced nuclear rainbow-like structure. Obtained experimental data show evidences of an important coupling of the elastic channel to the inelastic. Coupled channel calculations reproduce the experimental angular distributions when a re-normalization factor on the real part of the optical potential is introduced. A proper theoretical approach still requires a high degree of accuracy for the nuclear structure models and new tools to deal with collective excitations.

The MAGNEX large-acceptance spectrometer has been commissioned with beams from the Tandem accelerator at INFN-LNS Catania. The optics were tested with elastically-scattered 7Li, 16O and 48Ti beams with various apertures mounted after the target. The momentum dispersion was verified to be in agreement with the optics calculations. A demonstration of the particle identification capabilities of the PSD start detector and the focal plane detector was given by a measurement of the 27Al(7Li,6Li)28Al transfer reaction at a mean angle of 25°. The measured charge state distribution of 48Ti ions is in agreement with predictions for a gold stripping foil. Preliminary results of the software reconstruction of incident angle and excitation energy, obtained through matrices based on a 3D-interpolation of the measured field maps, are encouraging.

Angular distributions for the inelastic scattering of 13.0 MeV deuterons on 104;106;108;110Pd were measured with the Sao Paulo Pelletron-Enge-Spectrograph facility in the range of 12(0) < thetalab < 64(0). A Coulomb-Nuclear Interference analysis, employing the Distorted Wave Born Approximation with the Deformed Optical Model as transition potential, under well established global optical parameters, was applied to the first quadrupolar excitations. The values of C = / , the ratio of charge to isoscalar deformation lengths, and of ()² were extracted through the comparison of experimental and predicted cross section angular distributions. The ratios of reduced charge to isoscalar transition probabilities, B(EL) to B(ISL) respectively, are related to the square of the parameter C and were thus obtained with the advantage of scale uncertainties cancellation. For 104Pd, and preliminary for 108Pd, the respective values of C = 1.18(3) and C = 1.13(4) reveal an enhanced contribution of the protons relative to the neutrons to the excitation, while a smaller effect is found for 106Pd, C = 1.06(3) and for 110Pd, C = 1.07(3), in comparison with the value C = 1.00 expected for homogenous collective excitations.

The characteristic properties of the hot nuclear matter existing at the time of fragment formation in the multifragmentation events produced in the reaction $^{64}$Zn + $^{112}$Sn at 40 MeV/nucleon are studied. A kinematical focusing method is employed to determine the multiplicities of evaporated light particles, associated with isotopically identified detected fragments. From these data the primary isotopic yield distributions are reconstructed using a Monte Carlo method. The reconstructed yield distributions are in good agreement with the primary isotope distributions obtained from AMD transport model simulations. Utilizing the reconstructed yields, power distribution, Landau free energy, characteristic properties of the emitting source are examined. The primary mass distributions exhibit a power law distribution with the critical exponent, $A^{-2.3}$, for $A \geq 15$ isotopes, but significantly deviates from that for the lighter isotopes. Landau free energy plots show no strong signature of the first order phase transition. Based on the Modified Fisher Model, the ratios of the Coulomb and symmetry energy coefficients relative to the temperature, $a_{c}/T$ and $a_{sym}/T$, are extracted as a function of A. The extracted $a_{sym}/T$ values are compared with results of the AMD simulations using Gogny interactions with different density dependencies of the symmetry energy term. The calculated $a_{sym}/T$ values show a close relation to the symmetry energy at the density at the time of the fragment formation. From this relation the density of the fragmenting source is determined to be $\rho /\rho_{0} = (0.63 \pm 0.03 )$. Using this density, the symmetry energy coefficient and the temperature of fragmenting source are determined in a self-consistent manner as $a_{sym} = (24.7 \pm 3.4) MeV$ and $T=(4.9 \pm 0.2)$ MeV.

The main purpose of the present work is the investigation of the α-cluster phenomenon in 16 O. The 12 C( 6 Li,d) 16 O reaction was measured at a bombarding energy of 25.5 MeV employing the Sao Paulo Pelletron-Enge-Spectrograph facility and the nuclear emulsion detection technique. Resonant states around 4α threshold were measured and an energy resolution of 15 keV allows to define states previously unresolved. The angular distributions of the absolute cross sections were determined in a range of 4-40 degree in the center of mass system. The upper limit for the resonance widths was obtained, indicating that the α cluster structure information in this region should be revised.

Background: Resonances around $x\ensuremath{\alpha}$ thresholds in light nuclei are recognized to be important in basic aspects of nuclear structure. However, there is scarce experimental information associated with them.Purpose: We study the $\ensuremath{\alpha}$-clustering phenomenon in resonant states around the $4\ensuremath{\alpha}$ threshold (14.44 MeV) in the ${}^{16}\text{O}$ nucleus.Method: The ${}^{12}\text{C}{(}^{6}\text{Li},d){}^{16}\mathrm{O}$ reaction was investigated with an unprecedented resolution at a bombarding energy of 25.5 MeV by employing the S\~ao Paulo Pelletron-Enge-Spectrograph facility and the nuclear emulsion technique.Results: Several narrow resonances were populated and the energy resolution of 15 keV allows for the separation of doublet states that were not resolved previously. The upper limits for the resonance widths in this region were extracted. The angular distributions of the absolute differential cross section associated with four natural parity quasibound states are presented and compared to distorted wave Born approximation predictions.Conclusions: Narrow resonances not previously reported in the literature were observed. This indicates that the $\ensuremath{\alpha}$-cluster structure information in this region should be revised.

Information collected in the present high resolution study of 104Pd(d,t)103Pd is interpreted within the systematics of the A ~ 100 region. The paper complements data previously presented by the S.Paulo Group, which were taken with the Pelletron-Enge-Spectrograph facility. A one-to-one correspondence to gamma ray results for 103Pd, collected by the Nuclear Data Sheets (NDS), was achieved and at least four open questions were settled. More reliable spectroscopic strengths were extracted in the present study.

Low-lying levels of 103Pd have been investigated through the (d,t) reaction on 104Pd, at an incident deuteron energy of 15.0 MeV. Outgoing particles were momentum analyzed by an Enge magnetic spectrograph and detected in nuclear emulsion plates, with an energy resolution of 8 keV. Previous (d,t) work suffered from a much worse resolution than that here achieved. A partial analysis of the data obtained is reported, referring to six out of the fourteen scattering angles for which data were obtained. Angular distributions associated with eight of the thirteen levels seen up to 1.1 MeV of excitation have been compared to DWBA one-neutron pick-up predictions. Both, the attributed excitation energy values and the transferred angular momenta are in excellent agreement with the results of other kind of experiments, as tabulated by the Nuclear Data Sheets. Some peculiar structure characteristics, associated with the yrast 5/2+, 3/2+ and 7/2+ states found in the Ru chain could be recognized also in 103Pd, pointing to the possibility of a more global understanding of this transitional mass region.

The 9Be(6Li,d)13C and 12,13C(6Li,d)16,17O reactions were measured at the Sao Paulo Pelletron-Enge-Spectrograph facility at 25.5 MeV incident energy. The nuclear emulsion detection technique was applied. Several narrow resonances were populated up to approximately 17 MeV of excitation energy. An excellent energy resolution was obtained: 40 keV for 13C and 15-30 keV for 16O. The upper limit for the resonance widths were determined. Recently, d-a angular correlations were measured at θd = 0° with incident energy of 25 MeV using the LNS Tandem-MAGNEX Spectrometer facility.

Several narrow alpha resonant 16O states were detected through the 12C(6Li,d) reaction, in the range of 13.5 to 17.5 MeV of excitation energy. The reaction was measured at a bombarding energy of 25.5 MeV employing the Sao Paulo Pelletron-Enge-Spectrograph facility and the nuclear emulsion technique. Experimental angular distributions associated with natural parity quasi-bound states around the 4α threshold are presented and compared to DWBA predictions. The upper limit for the resonance widths obtained is near the energy resolution (15 keV).

The excitation energies of the primary hot isotopes in multifragmentation events are experimentally reconstructed in the reaction system 64Zn + 112Sn at 40 MeV/nucleon. A kinematical focusing method is employed to evaluate the multiplicities of the evaporated light particles associated with isotopically identified fragments with 3≤Z≤14. Angular distributions of the velocity spectra of light charged particles and neutrons associated with trigger isotopes are examined. A moving source fit is used to separate the kinematically correlated particles, evaporated from the parents of the detected isotopes, from the uncorrelated particles originating from other sources. The latter are evaluated experimentally relative to those in coincidence with the Li isotopes. A parameter, k, is used to adjust the yield of the uncorrelated particles for different trigger isotopes. For each experimentally detected isotope, the multiplicities, apparent temperatures, and k values for n, p, d, t, and α particles are extracted. Using the extracted values, the excitation energies of the primary hot isotopes are reconstructed employing a Monte Carlo method. The extracted excitation energies are in the range of 1 to 4 MeV/nucleon but show a significant decreasing trend as a function of A for a given Z of the isotopes. The results are compared with those of antisymmetrized molecular dynamics (AMD) and statistical multifragmentation model (SMM) simulations. While some of the experimental characteristics are predicted partially by each model, neither simulation reproduces the overall characteristics of the experimental results. © 2013 American Physical Society.

The preliminary results of the analysis of α-conjugate system 40Ca + 40Ca at 35MeV/A and comparison with results of Antisymmetrized Molecular Dynamics (AMD) calculations are presented. The experiment involving NIMROD-ISIS array was performed at the Cyclotron Institute, Texas A&M University and the main goal was to find Bose Einstein Condensate in nuclei.

A systematic study of the response of different nuclei to the (18O,16O) two-neutron transfer reaction at 84 MeV incident energy was pursued at the INFN-LNS in Catania (Italy).The experiments were performed using several solid targets from light (9Be, 11B, 12,13C, 16O, 28Si) to heavier ones (58,64Ni, 120Sn, 208Pb). The 16O ejectiles were detected at forward angles by the MAGNEX magnetic spectrometer and identified without the need of time of flight measurements. Exploiting the large momentum (≈ 25%) and angular (50 msr) acceptance of the spectrometer, energy spectra were obtained with a relevant yield up to about 20 MeV excitation energy.A common feature of the light nuclei spectra is the strong population of states with well known configuration of two-particle over a core and the appearance of unknown resonant structures in the continuum. These latter can reveal the excitation of a collective mode connected with the transfer of a pair.For the heavier nuclei as 66Ni a completely different behaviour is observed indicating the presence of more dissipative processes in the reaction mechanisms that hide the spectroscopic information.

In-medium phenomena of low density nuclear matter are studied using collisions of 47 A MeV 40 Ar and 64 Zn projectiles with 112Sn and 124Sn target nuclei. Low density equations of state are tested by confronting various models with the data. In-medium cluster binding energies and symmetry density are also studied at low densities. We find that models that account for in-medium effects in general describe the data better than models that do not.

Measurements of the density dependence of the free symmetry energy in low density clustered matter have been extended using the NIMROD multi-detector at Texas A&M University. Thermal coalescence models were employed to extract densities, $\rho$, and temperatures, $T$, for evolving systems formed in collisions of 47 $A$ MeV $^{40}$Ar + $^{112}$Sn,$^{124}$Sn and $^{64}$Zn + $^{112}$Sn, $^{124}$Sn. Densities of $0.03 \leq \rho/\rho_0 \leq 0.2$ and temperatures in the range 5 to 10 MeV have been sampled. The free symmetry energy coefficients are found to be in good agreement with values calculated using a quantum statistical model. Values of the corresponding symmetry energy coefficient are derived from the data using entropies derived from the model.

Clustering in low density nuclear matter has been investigated using the NIMROD multi-detector at Texas A&M University. Thermal coalescence modes were employed to extract densities, $\rho$, and temperatures, $T$, for evolving systems formed in collisions of 47 $A$ MeV $^{40}$Ar + $^{112}$Sn,$^{124}$Sn and $^{64}$Zn + $^{112}$Sn, $^{124}$Sn. The yields of $d$, $t$, $^{3}$He, and $^{4}$He have been determined at $\rho$ = 0.002 to 0.032 nucleons/fm$^{3}$ and $T$= 5 to 10 MeV. The experimentally derived equilibrium constants for $\alpha$ particle production are compared with those predicted by a number of astrophysical equations of state. The data provide important new constraints on the model calculations.

The focal plane detector of the MAGNEX large acceptance magnetic spectrometer is presented. It is based on a large low-pressure gas-filled tracker followed by a wall of silicon detectors to stop the particles. It has been designed for the stringent requirements from the ion optics and the foreseen use with heavy ions. The performances of the device are demonstrated using 4MeV/u oxygen beams. The results of the tests are described and discussed in view of the application of the particle identification and trajectory reconstruction techniques to recover the kinematic properties of the reaction products. They demonstrate the suitability of such detector in a wide range of experiments where low-energy thresholds, large-accepted solid angle, precise momentum measurement and good particle identification are needed.

The 13C(18O, 16O)15C reaction has been studied at 84 MeV incident energy. The ejectiles have been detected at forward angles and 15C excitation energy spectra have been obtained up to about 20 MeV. Several known bound and resonant states of 15C have been identified together with two unknown structures at 10.5 MeV ( FWHM = 2.5 MeV ) and 13.6 MeV ( FWHM = 2.5 MeV ). Calculations based on the removal of two uncorrelated neutrons from the projectile describe a significant part of the continuum observed in the energy spectra. In particular the structure at 10.5 MeV is dominated by a resonance of 15C near the C 13 + n + n threshold. Similar structures are found in nearby nuclei such as 14C and 11Be.

The 9Be(6Li,d)13C reaction was used to investigate alpha resonant states in 13C up to 15 MeV of excitation. The reaction was measured at a bombarding energy of 25.5 MeV employing the Sao Paulo Pelletron‐Enge‐Spectrograph facility and the nuclear emulsion detection technique. An energy resolution of 50 keV was obtained. Several narrow alpha resonant states not previously measured were detected, in particular the one at the (3α+n) threshold populated by an L = 2 transfer, revealing a 9Be+α component for the 1/2− cluster state candidate at this threshold. Experimental angular distributions are presented in comparison with DWBA predictions.

In medium binding energies and Mott points for $d$, $t$, $^3$He and $\alpha$ clusters in low density nuclear matter have been determined at specific combinations of temperature and density in low density nuclear matter produced in collisions of 47$A$ MeV $^{40}$Ar and $^{64}$Zn projectiles with $^{112}$Sn and $^{124}$Sn target nuclei. The experimentally derived values of the in medium modified binding energies are in good agreement with recent theoretical predictions based upon the implementation of Pauli blocking effects in a quantum statistical approach., Comment: 5 pages, 3 figures

Alpha resonant states in 13 C up to 15 MeV were excited by the 9 Be (6 Li , d )13 C reaction. The data were taken at a bombarding energy of 25.5 MeV employing the São Paulo-Pelletron-Enge Split Pole facility and the nuclear emulsion technique. The resolution of 50 keV allowed for the separation of the resonant contributions to the known 7/2- and (5/2-) states near the 9 Be + α threshold both associated with an L = 4 transfer. Several narrow alpha resonant states not previously measured were detected, in particular the one at the 3α + n threshold populated by an L = 2 transfer, revealing a 9Be + α component for the 1/2- cluster state candidate at this threshold.

Isotope yields have been analyzed within the framework of a Modified Fisher Model to study the power law yield distribution of isotopes in the multifragmentation regime. Using the ratio of the mass dependent symmetry energy coefficient relative to the temperature, $a_{sym}/T$, extracted in previous work and that of the pairing term, $a_{p}/T$, extracted from this work, and assuming that both reflect secondary decay processes, the experimentally observed isotope yields have been corrected for these effects. For a given I = N - Z value, the corrected yields of isotopes relative to the yield of $^{12}C$ show a power law distribution, $Y(N,Z)/Y(^{12}C) \sim A^{-\tau}$, in the mass range of $1 \le A \le 30$ and the distributions are almost identical for the different reactions studied. The observed power law distributions change systematically when I of the isotopes changes and the extracted $\tau$ value decreases from 3.9 to 1.0 as I increases from -1 to 3. These observations are well reproduced by a simple de-excitation model, which the power law distribution of the primary isotopes is determined to $\tau^{prim} = 2.4 \pm 0.2$, suggesting that the disassembling system at the time of the fragment formation is indeed at or very near the critical point., Comment: 5 pages, 5 figures

The relative isobaric yields of fragments produced in a series of heavy-ion-induced multifragmentation reactions have been analyzed in the framework of a modified Fisher model, primarily to determine the ratio of the symmetry energy coefficient to the temperature, a(sym)/T, as a function of fragment mass A. The extracted values increase from 5 to similar to 16 as A increases from 9 to 37. These values have been compared to the results of calculations using the antisymmetrized molecular dynamics (AMD) model together with the statistical decay code GEMINI. The calculated ratios are in good agreement with those extracted from the experiment. In contrast, the values extracted from the ratios of the primary isobars from the AMD model calculation are similar to 4 to 5 and show little variation with A. This observation indicates that the value of the symmetry energy coefficient derived from final fragment observables may be significantly different than the actual value at the time of fragment formation. The experimentally observed pairing effect is also studied within the same simulations. The Coulomb coefficient is also discussed.

The MAGNEX large‐acceptance ray‐tracing magnetic spectrometer has recently been used with beams from the INFN‐LNS Tandem accelerator. After an accurate commissioning, the instrument has started an ambitious experimental program. In the first experiment the 19F(7Li,7Be)19O charge‐exchange reaction was studied at 52 MeV incident energy. The 19O excitation energy spectrum was reconstructed and the angular distributions measured. The second experiment was aimed at the study of the 15C via the 13C(18O,16O)15C reaction at 84 MeV incident energy. The ejectiles where detected at forward angles and mass identified by means of an innovative technique. The 15C excitation energy spectra up to about 20 MeV were obtained with a 250 keV FWHM energy resolution. In addition to several known states, the spectra show two unknown resonant‐like structures at 11.4 and 14.0 MeV. The strong population of these structures, together with the measured widths, could indicate the collective nature of these states associated to a corr...

Recent heavy ion reaction studies aimed at elucidating the properties of low density matter produced in near Fermi-energies are discussed. At the lowest densities and temperatures large alpha mass fractions are observed. The symmetry free energies derived from isoscaling analyses are far above those obtained in common effective interaction calculations, reflecting cluster formation, primarily of alpha particles, not included in such calculations. Theoretical modeling of these results requires the consideration of cluster formation and medium modifications of cluster properties.

The 9Be(6Li,d)13C reaction was used to investigate alpha resonant states in 13C up to 13 MeV of excitation. The reaction was measured at a bombarding energy of 25.5 MeV employing the Sao Paulo Pelletron‐Enge‐Spectrograph facility and the nuclear emulsion detection technique. The resolution of 50 keV allowed for the separation of the resonant contributions to the known 7/2− at 10.753 MeV and (5/2−) at 10.818 MeV 13C states. The alpha resonance seen at the (3α+n) threshold was not previously reported. The experimental angular distributions are presented in comparison with DWBA predictions.

We discuss experimental evidence for a nuclear phase transition driven by the different concentration of neutrons to protons. Different ratios of the neutron to proton concentrations lead to different critical points for the phase transition. This is analogous to the phase transitions occurring in 4He-3He liquid mixtures. We present experimental results which reveal the N/A (or Z/A) dependence of the phase transition and discuss possible implications of these observations in terms of the Landau Free Energy description of critical phenomena., Comment: 14 pages, 18 figures

A study of the 15C states was pursued in 2008 at the Catania INFN‐LNS laboratory by the 13C(18O,16O)15C reaction at 84 MeV incident energy. The 16O ejectiles were detected at forward angles by the MAGNEX magnetic spectrometer. The spectra show several known low lying states up to about 7 MeV excitation energy as well as two unknown resonant structures at about 11.4 and 13.5 MeV. The strong excitation of these latter together with the measured width of about 2 MeV FWHM could indicate the presence of collective modes of excitation connected to the transfer of a correlated neutron pair.

A technique to interpolate complex three-dimensional field distributions such as those produced by large magnets is presented. It is based on a modified charge density method where the elementary sources of the magnetic field are image charges with Gaussian shape placed on a three-dimensional surface. The strengths of the charges are found as the solution of a best-fit problem, whose special features are discussed in detail. The method is tested against the measured field of the MAGNEX large acceptance quadrupole, showing a high level of accuracy together with an effective compensation of the effect of the experimental errors present in the data. In addition the model field is in general analytical and Maxwellian. As a consequence, the reliability of the presented technique to the challenging problem of trajectory reconstruction in modern large acceptance spectrometers is demonstrated.

The results of the field measurement of the large quadrupole magnet of the MAGNEX spectrometer are presented and analyzed in the view of the possible application of modern techniques of ray reconstruction. The experimental data are checked against the symmetry conditions expected for the magnet. The observed deviations are related both to imperfections on the magnet manufacturing and to the not ideal positioning of the measurement device. In particular a quantitative estimation of the experimental error in the alignment of the probe with respect to the magnet is achieved. The measured field is also compared with the results from three-dimensional finite elements calculation. The obtained discrepancies between the measured and calculated field are too large for a direct application of the latter to ray-reconstruction methods. Nevertheless, these calculations are reliably used to study the impact of the observed inaccuracies in the probe alignment on the overall precision of field reconstruction and to set quantitative constraints on the field interpolation algorithms.

A systematic study of the nuclei that can be described as an integer number of α particles plus three neutrons via the (7Li,7Be) reaction at about 8 MeV/u has shown the presence of Bound States Embedded in the Continuum in the energy spectra. These are experimental signatures of the dynamical correlations of an easily polarizable core with a single‐particle state of the valence neutron.

The MAGNEX large‐acceptance spectrometer was commissioned with beams from the LNS Tandem. First results of physical interest are presented. The obtained 10−3 energy resolution confirms the ambitious characteristic of the calculations and allows considering the instrument as an ideal tool for future studies in the field of nuclear spectroscopy and reaction mechanisms at incident energies not far form the Coulomb barrier.

We applied the digital pulse shape acquisition to the read out of the anode pads of the focal plane detector of the MAGNEX spectrometer in order to measure the position coordinates using digital signal processing.

There exists an intriguing problem when bosonic clusters as bound states of fermions are produced in the reaction, and the Bose character of the composite clusters competes with the fermionic properties of their constituents. In the analysis of 40 Ca + 40 Ca reactions at 35MeV/A we selected classes of projectile-like sources with exit channels consisting of only bosons, only fermions, only even-even nuclei, only odd - odd nuclei, only even - odd nuclei and only alpha-conjugate nuclei, respectively and searched for kinematic characteristics of these systems which might differ depending upon the type of matter selected. The distributions of various observables for the different classes of matter and comparisons between them will be presented and discussed.