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Background: Multinucleon transfer reactions (MNT) are a competitive tool to populate exotic neutron-rich nuclei in a wide region of nuclei, where other production methods have severe limitations or cannot be used at all. Purpose: Experimental information on the yields of MNT reactions in comparison with theoretical calculations are necessary to make predictions for the production of neutron-rich heavy nuclei. It is crucial to determine the fraction of MNT reaction products which are surviving neutron emission or fission at the high excitation energy after the nucleon exchange. Method: Multinucleon transfer reactions in Xe136+U238 have been measured in a high-resolution γ-ray/particle coincidence experiment. The large solid-angle magnetic spectrometer PRISMA coupled to the high-resolution Advanced Gamma Tracking Array (AGATA) has been employed. Beamlike reaction products after multinucleon transfer in the Xe region were identified and selected with the PRISMA spectrometer. Coincident particles were tagged by multichannel plate detectors placed at the grazing angle of the targetlike recoils inside the scattering chamber. Results: Mass yields have been extracted and compared with calculations based on the grazing model for MNT reactions. Kinematic coincidences between the binary reaction products, i.e., beamlike and targetlike nuclei, were exploited to obtain population yields for nuclei in the actinide region and compared to x-ray yields measured by AGATA. Conclusions: No sizable yield of actinide nuclei beyond Z=93 is found to perform nuclear structure investigations. In-beam γ-ray spectroscopy is feasible for few-neutron transfer channels in U and the −2p channel populating Th isotopes.

Multinucleon transfer reaction 40Ar+208Pb has been investigated with the PRISMACLARA experimental setup in LNL, INFN, Italy. The experimental differential cross sections have been obtained for different transfer channels by measuring more than Δθlab = 20◦ covered by three angular settings of PRISMA. Results have been compared with the semiclassical calculation GRAZING. Since the understanding of the reaction mechanism depends strongly on the determination of absolute cross section, effect of transport of ions through PRISMA has been studied via a Monte Carlo simulation code.

The level structures of the N = 50, 83As, 82Ge, and 81Ga isotones have been investigated by means of multi-nucleon transfer reactions. A first experiment was performed with the CLARA–PRISMA setup to identify these nuclei. A second experiment was carried out with the GASP array in order to deduce the γ -ray coincidence information. The results obtained on the high-spin states of such nuclei are used to test the stability of the N = 50 shell closure in the region of 78Ni (Z = 28). The comparison of the experimental level schemes with the shell-model calculations yields an N = 50 energy gap value of 4.7(3) MeV at Z = 28. This value, in a good agreement with the prediction of the finite-range liquid-drop model as well as with the recent large-scale shell model calculations, does not support a weakening of the N = 50 shell gap down to Z = 28.

Elastic, inelastic and one-nucleon transfer channels in the 48Ca+64Ni reaction have been mea- sured at ~ 6 MeV/A with the PRISMA-CLARA setup, at Legnaro National Laboratory, consisting in the coupling of a large solid angle magnetic spectrometer with a germanium array. By trajec- tory reconstruction the reaction products have been fully identi ed in mass, nuclear charge and kinetic energy, while coincident spectra of binary partners have been constructed after Doppler correction. Absolute di erential cross sections have been extracted for the inelastic excitation and one-nucleon transfer, also for speci c excited states. The data are in good agreement with semi-classical calculations and Distorted Wave Born approximation predictions. The work outlines an experimental method which can become valuable to extract structural information from heavy-ion reaction studies.

The neutron-rich Mn isotopes from A=59 to 63 have been studied through multi-nucleon transfer reactions by bombarding a 238U target with a beam of 70Zn at an energy of Elab=460 MeV. Prompt rays measured by the CLARA array have been identified unambiguously for each nucleus, using coincidence relationships with ions detected in the high-acceptance magnetic spectrometer PRISMA. The new data extends the knowledge of the low-lying level structure of Mn isotopes, which is discussed in terms of the systematics of the region. Results are compared with large-scale shell-model calculations using different effective interactions and valence spaces.

Excited states of N=22 Si-36, populated in deep-inelastic processes produced by the interaction of a 215 MeV beam of S-36 ions with a Pb-208 target, were studied in the present work. gamma rays from the binary fragments detected using CLARA, an array of 25 Ge Clover detectors, were measured in coincidence with projectile-like fragments detected by PRISMA, a large solid angle magnetic spectrometer. Two new gamma-ray photopeaks at energies of 1442 and 842 keV were observed and tentatively assigned to the 4(+)-> 2(+) and 6(+)-> 4(+) transitions, respectively. The systematics of the level structures of N=22 isotones are presented, and a comparison is made of the behavior of Si, Mg, and S isotopes. The level structure of Si-36 is also compared with the results of sdpf shell model calculations.

The CLARA-PRISMA Setup is a powerful tool for spectroscopic studies of neutron-rich nuclei produced in multi-nucleon transfer and deep-inelastic reactions. It combines the large acceptance spectrometer PRISMA with the gamma-ray array CLARA. Currently at LNL is being constructed the heavy-ion detector DANTE, based on Micro-Channel Plates, that will be installed at the CLARA-PRISMA setup. DANTE Will open the possibility of measuring gamma-gamma Doppler-corrected coincidences for the events outside the acceptance Of PRISMA. In this manuscript some results obtained with the CLARA-PRISMA setup will be discussed, in addition to the description and performance of the first prototype for the heavy-ion detector DANTE.

The reaction 48Ca+64Ni has been studied in the deep inelastic regime at approximately 6 MeV/A, by the CLARA-PRISMA setup. Angular distributions of the reaction cross sections have been obtained for the most intense reaction products, taking into account the response function of the magnetic spectrometer. The response of PRISMA has been calculated making use of a MonteCarlo simulation of the transport of the ions in the spectrometer, starting from known events distributions. For the one-nucleon transfer channels, the experimental data are in good agreement with predictions from a semiclassical multi-nucleon transfer model.