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The deep inelastic reaction (DIC) 48Ca+64Ni, at an energy approximately 2.5 times above the Coulomb barrier, was studied using the CLARA‐PRISMA setup at the Laboratori Nazionali di Legnaro. Total cross sections and angular distributions, both energy integrated and associated to the population of selected excited states, are measured for the most intense reaction channels. The γ‐decay of the most intense reaction products is also studied. The use of angular distributions and polarization measurements of γ transitions allows to firmly establish spin and parity of excited states. Both reaction and gamma spectroscopy studies demonstrate the relevance of DIC with heavy ions for the investigation of moderately neutron rich systems.

The transition strenghts for the low—lying levels of 122,124Ba have been determined analysing the Recoil Distance Doppler Shift data by the Differential Decay Curve Method. The trend of normalised B(E2) reveals a drop in correspondance of the 81+ state. This feature is also present in 122Ba: entering the backbending region the interplay between collective and quasiparticle degrees of freedom have to be carefully taken into account.

The lifetimes of excited states of the 122Ba ground—state band, populated via the 108Cd(16O,2n)122Ba and the 112Sn(13C,2n)122Ba reactions, have been measured using the Recoil Distance Doppler—Shift method. The level scheme of 122Ba has also been revised.

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.

The large solid angle magnetic spectrometer for heavy ions PRISMA was operated at LNL in conjunction with the highly efficient CLARA set‐up up to the end of March 2008. The AGATA Demonstrator is being mounted around the target area of PRISMA replacing the CLARA set‐up. It will allow to carry out nuclear structure and reaction mechanism studies with better resolution and higher statistics. New detectors for light ions and slow moving heavy ions have been designed for the focal plane of the spectrometer.

Two experimental setups have been used to study excited states of neutron‐rich nuclei in the A∼100 region. Extended level schemes and lifetime measurements were obtained using deep‐inelastic and fusion‐fission reactions with the CLARA‐PRISMA spectrometer and the Ge‐array GASP respectively. Experimental information from GASP has been used to complement the CLARA‐PRISMA experiment. Time spectra have been used to measure the lifetimes of isomeric states. Preliminary results are presented for 89Rb.

An investigation of γ‐ray fold distributions has been carried out for the 97Mo(51V,zα yp xn) reaction. For the α2n channel leading to 142Eu a double‐humped fold distribution was found. An explanation in terms of an incomplete‐fusion reaction mechanism is proposed.

The lifetimes of the first excited states of nuclei around the doubly‐magic nucleus 48Ca have been determined using a novel method that combines the Recoil Distance Doppler Shift (RDDS) method with the CLARA‐PRISMA spectrometers. This is the first time such a method is applied to measure lifetimes of neutron‐rich nuclei populated via a multinucleon transfer reaction. This novel method and some preliminary results on lifetimes are presented.

High‐spin states in 168Tm were investigated by means of γ‐ray spectroscopy techniques using the GASP multidetector array. Rotational bands have been established and identified in terms of their configurations.

The PRISMA‐CLARA setup, consisting of the large solid angle magnetic spectrometer for heavy‐ions PRISMA coupled to the highly efficient CLARA array of 25 Clovers detectors, was operating at LNL since the end of 2003. The first experimental campaign has been completed at the end of 2004. Selected results on the structure of moderately neutron‐rich nuclei, populated in multi‐nucleon transfer and deep‐inelastic reactions, are presented here. Some technical developments related to the setup are also discussed.

Recently, an intense experimental effort has been devoted to the search of empirical proofs of critical‐point symmetries in nuclear structure. These symmetries describe shape‐phase transitions and provide parameter‐free predictions (up to over‐all scale factors) for excitation spectra and B(E2) values. This contribution reports on recent plunger‐lifetime measurements ON 102Pd carried out at LNL, Legnaro, with the Cologne plunger apparatus coupled to the GASP spectrometer and using the 92Zr(13C,3n)102Pd reaction at 48 MeV. According to the results of our measurements, 102Pd is so far the best known paradigm of the E(5) critical‐point symmetry.

This contribution reports on the results of an experiment to study the near‐yrast states in selenium‐ and osmium‐like nuclei, following their population in thick‐target, multinucleon transfer reactions between an 82Se beam and a 192Os target. The experimental results for the level scheme for 84Se are presented together with investigations into the use of multi‐dimensional gamma‐ray energy gating to investigate angular momentum population in such heavy‐ion binary reactions.

Spectroscopic quadrupole moment measurements for high‐spin isomeric states in 192,193,194Pb nuclei have been performed by the time‐differential perturbed γ‐ray angular distribution method. The quadrupole moments of the isomers described by quasineutron configurations in neutron‐deficient Pb nuclei are well reproduced by the pairing plus quadrupole model, which predicts for these states a very small prolate deformation β2 ≈0.02. The quadrupole moment of the 11− isomeric state in 192Pb involving the π(3s1/2−2 1h9/2 1i13/2) configuration corresponds to a deformation β2=−0.11(1). The quadrupole moments of the proton intruder states in Pb nuclei are compared with theoretical predictions of tilted‐axis cranking, mean‐field and interacting boson models.

International audience; Measurements of the excitation energies of superdeformed states via the observation of single-step linking transitions have now been made in three even-A Pb nuclei, with a quasicontinuum analysis providing a limit in a fourth, odd-A case. These results allow us to take the first steps towards establishing systematic trends in excitation energies and binding energies in the second minimum in Pb isotopes

Radioactive beams a few nucleons away from the valley of stability are now becoming available with intensities sufficient for high-resolution γ-ray spectroscopy of exotic nuclei. Planned next-generation facilities will shift this intensity limit further to the boundaries of nuclear stability. To exploit the possibilities offered by radioactive beams dedicated γ detection arrays are required. In the near future the RISING project [1] will install EUROBALL Cluster and Clover detectors to investigate the nuclear structure of exotic beams provided from the SIS/FRS facility at GSI. To make best use of the proposed future facilities an Advanced GAmma Tracking Array [2] is currently under design. This 4π-array will be have highest efficiency selectivity and energy resolution capable to accept high event rates.

A complete study of the nuclear structure by means of gamma spectroscopy requires, in addition to the high resolution gamma measurement and accurate DCO's or angular distributions, the information concerning the Electric or Magnetic character of the transition. This information for transitions in nuclei far from stability valley is now reachable in the new generation of Ge-arrays based in composite detectors. EUROBALL III is a good example with the high polarization sensitivity of the 90 degrees ring of Clovers. The Polarization correlations PCO's measured in coincidence with the Cluster detectors permits to investigate transitions in weakly populated nuclei. In this contribution we present results on medium mass N=Z nuclei measured with EUROBALL III coupled with light particle ancillary detectors. (Less)

The high-spin states of the N=Z nucleus 64Ge have been investigated using the EUROBALL array coupled to the ISIS Si-ball and to a highly efficient n-Wall. Spins and parities were assigned on the basis of a DCO and of a polarization analysis.

The results of recent experiments performed at L.N.L. on multiple octupole excitations in the N=84 isotones are reviewed. In particular, the results on B(E3) strengths in 146Sm are discussed and expectations for higher-order octupole excitations are compared with the present experimental situation.

The high-spin structure of the N≃Z nuclei 62,64,65Ga have been investigated using the EUROBALL array coupled to the ISIS Si-ball. The collective bands of such nuclei are then compared showing an unexpected behavior.

A variety of collective phenomena is proven to occur at the middle of the 1f7/2 shell, which can be microscopically described by Shell Model calculations. For this purpose a detailed spectroscopy as well as precise DSAM lifetime measurements were performed. The cases of 48,49,50Cr are illustrated.