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The excitation of the dynamical dipole mode along the fusion path was investigated for the first time in the formation of a heavy compound nucleus in the A ∼ 190 mass region. The compound nucleus was formed at identical conditions of excitation energy and spin from two entrance channels: the charge-asymmetric 40 Ca + 152 Sm and the nearly charge-symmetric 48 Ca + 144 Sm at E lab = 11 and 10.1 MeV / nucleon, respectively. High-energy γ rays and light charged particles were measured in coincidence with evaporation residues by means of the MEDEA multidetector array (Laboratori Nazionali del Sud, Italy) coupled to four parallel plate avalanche counters. The charged particle multiplicity spectra and angular distributions were used to pin down the average excitation energy, the average mass, and the average charge of the compound nucleus. The γ -ray multiplicity spectrum and angular distribution related to the nearly charge-symmetric channel were employed to obtain new data on the giant dipole resonance in the compound nucleus. The dynamical dipole mode excitation in the charge-asymmetric channel was evidenced, in a model-independent way, by comparing the γ -ray multiplicity spectra and angular distributions of the two entrance channels with each other. Calculations of the dynamical dipole mode in the 40 Ca + 152 Sm channel, based on a collective bremsstrahlung analysis of the reaction dynamics, are presented. Possible interesting implications in the superheavy-element quest are discussed.

The excitation of the dynamical dipole mode along the fusion path was investigated for the first time in the formation of a heavy compound nucleus in the $A\ensuremath{\sim}190$ mass region. The compound nucleus was formed at identical conditions of excitation energy and spin from two entrance channels: the charge-asymmetric $^{40}\mathrm{Ca}+^{152}\mathrm{Sm}$ and the nearly charge-symmetric $^{48}\mathrm{Ca}+^{144}\mathrm{Sm}$ at ${E}_{\text{lab}}=11$ and 10.1 MeV/nucleon, respectively. High-energy $\ensuremath{\gamma}$ rays and light charged particles were measured in coincidence with evaporation residues by means of the MEDEA multidetector array (Laboratori Nazionali del Sud, Italy) coupled to four parallel plate avalanche counters. The charged particle multiplicity spectra and angular distributions were used to pin down the average excitation energy, the average mass, and the average charge of the compound nucleus. The $\ensuremath{\gamma}$-ray multiplicity spectrum and angular distribution related to the nearly charge-symmetric channel were employed to obtain new data on the giant dipole resonance in the compound nucleus. The dynamical dipole mode excitation in the charge-asymmetric channel was evidenced, in a model-independent way, by comparing the $\ensuremath{\gamma}$-ray multiplicity spectra and angular distributions of the two entrance channels with each other. Calculations of the dynamical dipole mode in the $^{40}\mathrm{Ca}+^{152}\mathrm{Sm}$ channel, based on a collective bremsstrahlung analysis of the reaction dynamics, are presented. Possible interesting implications in the superheavy-element quest are discussed.

Proton elastic scattering and inelastic scattering to the first excited state of 6He have been measured over a wide angular range using a 40.9A MeV 6He beam. The data have been analyzed with a fully microscopic model of proton-nucleus scattering using 6He wave functions generated from large space shell model calculations. The inelastic scattering data show a remarkable sensitivity to the halo structure of 6He., Comment: 9 pages, 3 figures. RevTeX. Replaced figure 3 with updated figure

We describe the experimental set-up of the Radioactive Ion Beam (RIB) in-flight facility EXOTIC consisting of: (a) two position-sensitive Parallel Plate Avalanche Counters (PPACs), dedicated to the event-by-event tracking of the produced RIBs and to time of flight measurements and (b) the new high-granularity compact telescope array EXPADES (EXotic PArticle DEtection System), designed for nuclear physics and nuclear astrophysics experiments employing low-energy light RIBs. EXPADES consists of eight Δ E – E res telescopes arranged in a cylindrical configuration around the target. Each telescope is made up of two Double Sided Silicon Strip Detectors (DSSSDs) with a thickness of 40/60 μm and 300 μm for the Δ E and Eres layer, respectively. Additionally, eight ionization chambers were constructed to be used as an alternative Δ E stage or, in conjunction with the entire DSSSD array, to build up more complex triple telescopes. New low-noise multi-channel charge-sensitive preamplifiers and spectroscopy amplifiers, associated with constant fraction discriminators, peak-and-hold and Time to Amplitude Converter circuits were developed for the electronic readout of the Δ E stage. Application Specific Integrated Circuit-based electronics was employed for the treatment of the Eres signals. An 8-channel, 12-bit multi-sampling 50 MHz Analog to Digital Converter, a Trigger Supervisor Board for handling the trigger signals of the whole experimental set-up and an ad hoc data acquisition system were also developed. The performance of the PPACs, EXPADES and of the associated electronics was obtained offline with standard α calibration sources and in-beam by measuring the scattering process for the systems 17O+58Ni and 17O+208Pb at incident energies around their respective Coulomb barriers and, successively, during the first experimental runs with the RIBs of the EXOTIC facility.

We developed a Monte-Carlo code for describing the reaction kinematics of the two-body direct processes employed of the EXOTIC beam-line of the Laboratori Nazionali di Legnaro (LNL) for the production of light weakly bound radioactive ion beams at energies of a few MeV/u. The program calculates the phase-space distribution of both primary and secondary beams at the target exit and uses these quantities to optimize the secondary beam selection with the EXOTIC spectrometer. The calculations have been performed and compared with the available experimental data for two reactions: (1)H(2)((17)O, (17)F)n and (3)He((6)Li, (8)B)n. (c) 2008 Elsevier B.V. All rights reserved.

The energy spectra of the γ-rays emitted in the 35Cl + 92Mo reaction at incident energy E = 260 MeV were measured in coincidence with the ejectiles produced in dissipative reaction events. The cumulative energy spectrum of the γ-rays coming from the decay of the ejectiles was calculated within the statistical model and its comparison to the experimental spectrum evidences an excess in the data for Eγ = 8 to 12 MeV. Such an excess, fitted with a Lorentz curve, is attributed to the preequilibrium GDR γ-decay of the intermediate dinuclear system. The centroid energy of the Lorentz curve corresponds to a dipole oscillation along the symmetry axis of the system and its width is found to be comparable to that of the ground state GDR low energy component of the deformed dinucleus. The small quantal dispersion Δl = (10.3 ± 0.1)ħ of the entrance channel angular momentum, determined by analysing the dissipative fragment angular distribution in the framework of the Strutinsky model, is suggested to limit the broadening of the preequilibrium GDR width.

The energy and angular distributions of $^{3}\mathrm{He}$ and $^{4}\mathrm{He}$ ions produced in the $^{7}\mathrm{Be}\phantom{\rule{4pt}{0ex}}+\phantom{\rule{4pt}{0ex}}^{58}\mathrm{Ni}$ reaction at a bombarding energy of 22 MeV have been measured for the first time. The yield of the heavier helium isotope was four to five times more abundant than that of its lighter counterpart, ruling out the possibility that in this energy range the $^{7}\mathrm{Be}$ reaction dynamics is dominated by the exclusive breakup process $^{7}\mathrm{Be}\phantom{\rule{4pt}{0ex}}\ensuremath{\rightarrow}{\phantom{\rule{4pt}{0ex}}}^{3}\mathrm{He}\phantom{\rule{4pt}{0ex}}+\phantom{\rule{4pt}{0ex}}^{4}\mathrm{He}$ (${S}_{\ensuremath{\alpha}}=1.586$ MeV). Extensive kinematic and theoretical calculations suggest that the $^{3}\mathrm{He}$ ions mostly originate from the $^{4}\mathrm{He}$-stripping process and the $^{4}\mathrm{He}$ production is mainly triggered by the fusion-evaporation channel. The role played by the breakup, $^{3}\mathrm{He}$-stripping, $1n$-stripping, and $1n$-pickup processes is also discussed.

We studied the reaction dynamics induced at Coulomb barrier energies by the weakly-bound Radioactive Ion Beam 7Be (Sα = 1.586 MeV) on medium-mass (58Ni) and heavy (208Pb) targets. The experiments were performed at INFN-LNL (Italy), where a 2-3×105 pps 7Be secondary beam was produced with the RIB in-flight facility EXOTIC. Charged reaction products were detected by means of high-granularity silicon detectors in rather wide angular ranges. The contribution presents an up-to-date status of the data analysis and theoretical interpretation for both systems. European Commission, Seventh Framework Programme 600376

The study of reactions induced by exotic weakly bound nuclei at energies around the Coulomb barrier had attracted a large interest in the last decade, since the features of these nuclei can deeply affect the reaction dynamics. The discrimination between different reaction mechanisms is, in general, a rather difficult task. It can be achieved by using detector arrays covering high solid angle and with high granularity that allow to measure the reaction products and, possibly, coincidences between them, as, for example, recently done for stable weakly bound nuclei [1, 2]. We investigated the collision of the weakly bound nucleus Be-7 on a Ni-58 target at the beam energy of 1.1 times the Coulomb barrier, measuring the elastic scattering angular distribution and the energy and angular distributions of He-3 and He-4. The Be-7 radioactive ion beam was produced by the facility EXOTIC at INFN-LNL with an energy of 22 MeV and an intensity of similar to 3x10(5) pps. Results showed that the He-4 yeld is about 4 times larger than He-3 yield, suggesting that reaction mechanisms other than the break-up mostly produce the He isotopes. Theoretical calculations for transfer channels and compound nucleus reactions suggest that complete fusion accounts for (41 +/- 5%) of the total reaction cross section extracted from optical model analysis of the elastic scattering data, and that He-3 and He-4 stripping are the most populated reaction channels among direct processes. Eventually estimation of incomplete fusion contributions to the He-3,He-4 production cross sections was performed through semi-classical calculations with the code PLATYPUS [3].

The existence of the dynamical dipole mode in the 192Pb composite system was investigated, through the study of its prompt γ decay, employing the 40Ca+152Sm and 48Ca+144Sm reactions at Elab=11 and 10.1 MeV/nucleon, respectively. The γ-rays and light charged particles were detected in coincidence with evaporation residues and fission fragments. First results of this experiment show that the dynamical dipole mode survives in collisions involving heavier mass reaction partners than those studied previously. As a fast cooling mechanism on the fusion path, the prompt dipole γ radiation could be of interest for the synthesis of super-heavy elements through "hot" fusion reactions. Furthermore, by using radioactive beams and the prompt γ radiation as a probe we could get information on the symmetry energy at sub-saturation densities.

A low threshold charged particle three-stage detector has been designed, built and successfully tested. A truncated pyramidal geometry has been chosen to use the device as an element in a large solid angle array for heavy ion nuclear experiments. Angular resolution of 0.4° at 35 cm from the target, energy resolution of about 1% for the elastically scattered ions and Z resolving power of 63 for Z = 17 have been achieved in the 35 Cl+ 64 Ni reaction at 280 MeV incident energy.

We have studied the elastic scattering of the exotic 17 F nuclei from 208 Pb at Coulomb barrier energies. For the measurement we used a new detector array with pixel structure and a large solid angle. Optical potential analysis shows that 17 F has an imaginary potential much less deep than 19 F. Information on the exclusive 17 F breakup cross section has been deduced too.

The heavy-ion magnetic spectrometer PRISMA was recently installed at Laboratori Naz. di Legnaro, in order to exploit the heavy-ion beams of the XTU Tandem-ALPI-PIAVE accelerator complex, with masses up to A≃200 at energies ≃5-10 MeV MeV A.

The existence of the dynamical dipole mode in the 192 Pb composite system was investigated through the study of its prompt γ decay employing the 40 Ca + 152 Sm and 48 Ca + 144 Sm reactions at E lab =11 and 10.1 MeV/u, respectively. The γ -rays and light charged particles were detected in coincidence with evaporation residues and fission fragments. First results of this experiment show that the dynamical dipole mode survives in collisions involving heavier mass reaction partners than those studied previously. As a fast cooling mechanism on the fusion path, the prompt dipole γ radiation could be of interest for the synthesis of super-heavy elements through ”hot” fusion reactions. Furthermore, by using radioactive beams and the prompt γ radiation as a probe we could get information on the symmetry energy at sub-saturation densities.

The prompt γ‐ray emission related with the dynamical dipole mode decay was investigated in the 192Pb mass region by means of the 40Ca+152Sm and 48Ca+144Sm fusion‐evaporation and fission reactions at Elab = 11 and 10.1 MeV/nucleon, respectively. The two reactions populate, through entrance channel having different charge asymmetries, the 192Pb compound nucleus at an excitation energy of 236 MeV with identical spin distribution. Preliminary results of this experiment show that the dynamical dipole mode survives in collisions involving heavier mass reaction partners than those studied previously. As a fast cooling mechanism on the fusion path, the prompt dipole γ radiation could be of interest for the synthesis of super‐heavy elements through “hot” fusion reactions.

The dynamical dipole mode, excited in charge asymmetric heavy-ion collisions, was investigated in the mass region of the 192 Pb compound nucleus, formed by using the 40,48 Ca + 152,144 Sm reactions at ∼11 MeV/nucleon. Preliminary results of this measurement, concerning both fusion-evaporation and fission events are presented. As a fast cooling mechanism on the fusion path, the dynamical dipole mode could be useful for the synthesis of super heavy elements through “hot” fusion reactions.

High-energy {gamma} rays and light charged particles from the {sup 36}Ar+{sup 96}Zr and {sup 40}Ar+{sup 92}Zr reactions at E{sub lab}=16 and 15.1 MeV/nucleon, respectively, were measured in coincidence with evaporation residues by means of the MEDEA multidetector array coupled to four parallel plate avalanche counters. The aim of this experiment was to investigate the prompt {gamma} radiation, emitted in the decay of the dynamical dipole mode, in the {approx}16 MeV/nucleon energy range and to map its beam energy dependence, comparing the present results with our previous ones obtained at lower energies. The studied reactions populate, through entrance channels having different charge asymmetries, a compound nucleus in the region of Ce under the same conditions of excitation energy and spin. Light charged particle energy spectra were used to pin down the average excitation energy and the average mass of the system. By studying the {gamma}-ray spectra of the charge symmetric reaction {sup 40}Ar+{sup 92}Zr, the statistical giant dipole resonance (GDR) parameters and angular distribution were extracted, and a comparison of the linearized 90 deg. {gamma}-ray spectra of the two reactions revealed a 12% extra yield in the GDR energy region for the more charge asymmetric system. The center-of-mass angular distribution datamore » of this extra {gamma} yield, compatible with a dipole oscillating along the symmetry axis of the dinuclear system, support its dynamical nature. The experimental findings are compared with theoretical predictions performed within a Boltzmann-Nordheim-Vlasov transport model and based on a collective bremsstrahlung analysis of the entrance channel reaction dynamics. An interesting sensitivity to the symmetry term of the equation of state and to in-medium effects on nucleon-nucleon (nn) cross sections is finally discussed.« less

Elastic scattering has been studied for the collisions induced by 17 O on 58 Ni target at energies around and above the Coulomb barrier. The elastic scattering angular distributions were measured for several energies and were analyzed within the framework of the optical model to obtain total reaction cross sections. The reaction cross-sections of the tightly bound 17 O were compared with those of weakly bound 17 F on the same targets in order to investigate the e ects of the low binding energy in the reaction dynamics.

We measured for the first time Be-7 elastically scattered nuclei as well as He-3,He-4 reaction products from a Ni-58 target at 22.3 MeV beam energy. The data were analyzed within the optical model formalism to extract the total reaction cross section. Extensive kinematical, Distorted Wave Born Approximation (DWBA) and Continuum Discretized Coupled Channel (CDCC) calculations were performed to investigate the He-3,He-4 originating mechanisms and the interplay between different reaction channels.

Intermediate mass fragments (IMF) and light particles emitted from the Ni-58 + Ni-58 reaction at a beam energy of 375 MeV have been studied. The fragments and light particles were measured in coincidence with 4 pi gamma-ray spectrometer. The Z=6 (C) kinetic energy spectra and the distribution of the final nuclei in coincidence with the emitted C are well described by Hauser-Feshbach calculations extended to many channels. A detailed study of C-Psi and 3 alpha-gamma correlations indicate a strong selectivity of the IMF decay. Our results indicate that the IMF can populate nuclei that are not accessible via multiple light particle (Z

Following the commissioning of the PRISMA large-acceptance spectrometer, installed at the Laboratori Nazionali di Legnaro (LNL), an international nuclear-structure collaboration has started to develop a large γ-ray setup to be installed in the target position of the spectrometer. The array is based on the EUROBALL composite CLOVER detectors. In this contribution the CLOVER detector array is described and its expected performance figures discussed. This new setup, by using the high-intensity heavyion beams provided by the LNL ALPI linac, will push the study of nuclear structure towards moderately neutron-rich nuclei by means of quasi-elastic and deep inelastic reactions.

The quasi elastic scattering of a 17O projectile from a 58Ni target has been studied at beam energies ranging from 42.5 to 55.0 MeV in 2.5 MeV steps. The total reaction cross sections were derived from the measured angular distributions by using an optical model fit within the coupled-channel code FRESCO. These cross sections are very similar to those measured for 17F (loosely bound by 0.6 MeV), mirror nucleus of 17O (tightly bound by 4.14 MeV). This outcome points out that, in this energy range, the small binding energy of the 17F valence proton has negligible influence onto the reactivity of such a loosely bound projectile, contrary to simple expectations, and to what observed for other loosely bound nuclei. The reaction dynamics seems to be influenced mainly by the Coulomb interaction which is similar for both mirror projectiles.

We measured for the first time the scattering process of 7 Be nuclei from a 58 Ni target at 23.2 MeV beam energy. The experiment was performed at the Laboratori Nazionali di Legnaro (LNL, Italy), where the 7 Be Radioactive Ion Beam was in-flight produced with the facility EXOTIC. Charged reaction products were detected by means of the detector array DINEX, arranged in a cylindrical configuration around the target to ensure a polar angle coverage in the ranges θ cm = 40°-80° and 110°-150°. The scattering differential cross section was analyzed within the optical model formalism with the coupled-channel code FRESCO to extract the total reaction cross section. The result was compared with those obtained at lower beam energies in an earlier experiment performed at the University of Notre Dame (USA). At the present stage of our analysis, the two data sets were found to be not fully consistent each other. Journal of Physics: Conference Series

We measured for the first time the scattering process of Be-7 nuclei from a Ni-58 target at 23.2 MeV beam energy. The experiment was performed at the Laboratori Nazionali di Legnaro (LNL, Italy), where the Be-7 Radioactive Ion Beam was in-flight produced with the facility EXOTIC. Charged reaction products were detected by means of the detector array DINEX, arranged in a cylindrical configuration around the target to ensure a polar angle coverage in the ranges theta(cm) = 40 degrees-80 degrees and 110 degrees-150 degrees. The scattering differential cross section was analyzed within the optical model formalism with the coupled-channel code FRESCO to extract the total reaction cross section. The result was compared with those obtained at lower beam energies in an earlier experiment performed at the University of Notre Dame (USA). At the present stage of our analysis, the two data sets were found to be not fully consistent each other.

We measured for the first time the scattering process of 7Be nuclei from a 58Ni target at 23.2 MeV beam energy. The experiment was performed at the Laboratori Nazionali di Legnaro (LNL, Italy), where the 7Be Radioactive Ion Beam was in-flight produced with the facility EXOTIC. Charged reaction products were detected by means of the detector array DINEX, arranged in a cylindrical configuration around the target to ensure a polar angle coverage in the ranges θcm = 40°-80° and 110°-150°. The scattering differential cross section was analyzed within the optical model formalism with the coupled-channel code FRESCO to extract the total reaction cross section. The result was compared with those obtained at lower beam energies in an earlier experiment performed at the University of Notre Dame (USA). At the present stage of our analysis, the two data sets were found to be not fully consistent each other.

The yield of γ-rays emitted in the dissipative reaction 19F + 12C, at Elab = 121.7 MeV has been measured in coincidence with α-particles emitted at θlab = 10°. Comparison with preliminary statistical model calculations shows that assuming only compound nucleaus formation is not sufficient to reproduce the data. Other mechanisms have to be included before information on reaction dynamics can be extracted and definitive conclusions can be drawn.

A. Pakou1, N. Patronis1, D. Pierroutsakou2, A.M. Sanchez-Benitez3, L. Acosta3,4, N. Alamanos5, A. Boiano2, G. Inglima6, D. Filipescu7, T. Glodariu7, A. Guglielmetti8, M. La Commara6, G. Lalazissis9, I. Martel3, C. Mazzocchi8, M. Mazzocco10, P. Molini10, C. Parascandolo2, M. Sandoli6, C. Signorini10, R. Silvestri6, F. Soramel10, M. Romoli2, E. Stiliaris11, A. Trzcinska12, K. Zerva1, E. Vardaci6, A. Vitturi10.

Non-statistical gamma rays of energy ranging in the interval from 5 MeV to 12 MeV are found to be emitted in coincidence with projectile-like fragments from the quasi-elastic 28 Si + 64 Ni reaction measured at E lab = 143 MeV. Boltzmann-Nordheim- Vlasov calculations are consistent with the hypothesis that they are originated from surface oscillations, of quadrupole or higher multipolarity, of the two colliding nuclei.

Charged reaction products originated from the interaction of the loosely bound radioactive ion beam {sup 17}F (S{sub p}=600 keV) with the proton-shell closed {sup 58}Ni target were measured at two colliding energies slightly above the Coulomb barrier. The collected data were analyzed within the framework of the optical model to deduce the reaction cross section and to investigate the role played by inelastic excitations, transfer channels, and the breakup process {sup 17}F{yields}{sup 16}O+p at near-barrier energies. The reaction cross section at the lower {sup 17}F energy showed a moderate enhancement ({approx}20%) with respect to that of the system {sup 16}O+{sup 58}Ni. At this energy direct reaction channels were also found to be more relevant than those for the reaction induced from the tightly bound projectile {sup 16}O on the same target. Both features could be strongly related to the very low binding energy of the {sup 17}F valence proton.

The interaction of loosely bound (S p = 600 keV) 17F ions with a 208Pb target was studied at E lab = 86 MeV, below the Coulomb barrier, by measuring the differential cross-section for the quasi-elastic scattering and the cross-section for the exclusive breakup process 17F $ \rightarrow$ 16O + p . The small reaction and exclusive breakup cross-sections confirm the small reactivity of this system, even at low energy, and indicates that the 17F small binding energy plays a minor role in the reaction dynamics.

We studied the elastic scattering process for the system (17)F + (58)Ni at two colliding energies slightly above the Coulomb barrier. The experimental data were analyzed within the framework of the optical model to investigate the effects of the projectile small binding energy (S(p) = 600 keV) on the reaction dynamics. We found that in this energy range the "reduced" reaction cross section for the system (17)F + (58)Ni is rather similar to that induced by the interaction of tightly-bound (16)O nuclei on the same target. Nuclear Physics A

A new facility, named EXOTIC, for the in‐flight production of light low‐energy weakly bound Radioactive Ion Beams (RIBs) is now fully operational at the Laboratori Nazionali di Legnaro (LNL) of the INFN. In this contribution we will present the facility, the Monte‐Carlo code we developed to properly describe the reaction dynamics inside the production target, the experimental results achieved and a list of possible RIBs delivered from the facility EXOTIC in the next future.

We investigated the dynamical dipole mode, related with entrance channel charge asymmetry effects, in the 40Ar+92Zr and 36Ar+96Zr fusion reactions at Elab = 15.1 A and 16 A MeV, respectively. These reactions populate, through entrance channels having different charge asymmetries, a compound nucleus in the A = 126 mass energy region, identical spin distribution at an average excitation energy of about 280 MeV. The compound nucleus average excitation energy and average mass were deduced by the analysis of the light charged particle energy spectra. By studying the γ‐ray energy spectra and the γ‐ray angular distributions of the considered reactions, the dynamical nature of the prompt radiation related to the dynamical dipole mode was evidenced. The data are compared with calculations based on a collective bremsstrahlung analysis of the reaction dynamics.

A new beam line is now fully operational at Laboratori Nazionali di Legnaro (LNL) TANDEM/ALPI accelerator for the in-flight production of light low-energy Radioactive Nuclear Beams (RNBs). The RNBs are produced by inverse kinematics reactions induced by heavy ions, such as 17O and 6Li, on 1H and 3He gas targets. The beam line has a large solid angle acceptance ( Δ Ω = 10 msr ) and a high rejection capability of spurious beams due to the combined action of magnetic rigidity and velocity filtering. A very pure (100%) and high intensity ( 3.6 × 10 6 pps ) 17 F 9 + secondary beam at E lab = 86 ± 1 MeV has been produced and used for experiments. A 8 B 5 + beam at E lab = 33 MeV , with a production rate of ∼ 2 × 10 3 pps , is presently under commissioning.

The prompt γ-ray emission is investigated in the 16 A MeV energy region by means of the 36,40Ar + 96,92Zr fusion reactions leading to a compound nucleus in the vicinity of 132Ce. The dynamical nature of this radiation is confirmed. We show that the prompt γ radiation has an angular distribution pattern consistent with a dipole oscillation along the symmetry axis of the dinuclear system. The data are compared with calculations based on a collective bremsstrahlung analysis of the reaction dynamics.

A new detection apparatus, named EXPADES (EXotic PArticle DEtection System), has been expressly designed to be used in nuclear physics experiments involving exotic beams and devoted to the study of nuclear reactions (scattering, direct reactions, breakup…) at energies around the Coulomb barrier. It consists of double-side segmented silicon detectors arranged in a compact configuration around the target. A very large solid angle, a wide angular range, high granularity and a highly miniaturized readout electronics, based on a new production commercial ASIC chipset, are the main features of the system.

Coherence energies extracted from excitation functions and angular distributions for the fragments emitted in the19F+63Cu reaction, measured in the range θlab=10° to 120° at incident energies between 100 to 108 MeV (lab.), were compared to the Kun model of dissipative collisions. An overall agreement was found for the angular distributions at forward angles. The general behavior of coherence energies was also properly described and interaction times were deduced.

A coincidence experiment was performed on the24Mg(16O,12Cα) reaction at an incident energy of 84.6 MeV. The measured relative energy spectra show the excitation of16O selected states decaying into the α-12C channel.

Elastic scattering angular distributions of $^{32,36}\mathrm{S}$ (beams)${+}^{58.64}$Ni have been measured at several energies around the Coulomb barrier. An optical-model analysis of the data reveals remarkable energy dependences of the potentials at the strong absorption radii, in all cases. The largest effects are observed for $^{32}\mathrm{r}$/rS${+}^{64}$Ni. This is due to the coupled reaction channels which also strongly influence the sub-barrier fusion cross sections. Coupled-channels calculations of elastic scattering and fusion have been performed, including the inelastic excitations of projectile and target; the need for considering additional (transfer) channels is made evident. We also have indications that sub-barrier fusion is not merely tunneling through a potential barrier, although energy dependent, as absorption into fusion takes place at larger internuclear distances. Older fusion and quasielastic transfer data are overviewed and compared with the reaction cross sections extracted from elastic scattering. Open questions still remain about the role of specific channels in determining the observed isotopic differences.

A data transfer problem using FERA modules was found in a heavy ion nuclear physics experiment. The source of the problem was spotted in the handling of some signals on the FERA control bus. A modification of this handling is proposed and performed by means of a new CAMAC-FERA control module, the EBOFERA. Furthermore, this module has a number of useful features like the master gate and clear signals handling, event tagging, pattern unit and event counter.

PRISMA is a magnetic spectrometer installed at Laboratori Nazionali di Legnaro (Italy) and designed for A=100– 200, E=5– 10 MeV-per-nucleon beams, and for possible use with the proposed radioactive beam facility SPES. The foremost features of the instrument are presented, along with the outline of two data analyses exemplifying the effectiveness of PRISMA-CLARA in studies of reaction dynamics.

The elastic scattering process for 11Be ions impinging on a 209Bi target was studied in the energy range around the Coulomb barrier. The angular distributions of the 11Be scattered particles were analyzed within the optical model framework in order to evaluate the reaction cross section, which turned out to be much larger than the fusion one, especially in the sub-barrier region. The comparison with the system 9Be + 209Bi showed that the reaction cross section is larger for the reaction 11Be + 209Bi in the energy range around the Coulomb barrier, while they are rather similar at higher bombarding energies. This result suggests that direct processes related to the 11Be halo structure and lower binding energy are more relevant at near-barrier energies.

We present the new facility EXOTIC at Legnaro National Laboratories (LNL), dedicated to the in flight production of light exotic beams at near-barrier energies. The radioactive beams are produced via inverse kinematics mode of intense TANDEM beams hitting on light gas targets. The first beams, 17F and 8B, were produced with very low contaminant background and with an intensity of $\sim\kern-3pt 10^6$ and $\sim\kern-3pt 10^4$ pps, respectively. In the first measurement performed with the EXOTIC facility we studied the elastic scattering and the two-body breakup process of the 17F radioactive beam on a 208Pb target at Elab=86MeV. Preliminary results of this experiment, aiming at the investigation of the reaction mechanisms of the loosely bound 17F nucleus at subbarrier energies, show a rather small two-body breakup cross section.