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The first ever achieved full identification of both fission fragments, in atomic and mass number, made it possible to define new observables sensitive to the fission dynamics along the fission path up to the scission point. Moreover, proton-induced fission of 208Pb at high energies offers optimal conditions for the investigation of dissipative, and transient effects, because of the high-excitation energy of the fissioning nuclei, its low angular momentum, and limited shape distortion by the reaction. In this work we show that the charge distribution of the final fission fragments can constrain the ground-to-saddle dynamics while the mass distribution is sensitive to the dynamics until the scission point. [ABSTRACT FROM AUTHOR]

Advanced nuclear structure models predict the presence of the shell closures N = 14, 16 in neutron-rich O isotopes rather than N = 20. Spectroscopic investigations performed at the neutron drip line have recently confirmed such predictions showing that the 24O is a doubly magic nucleus (Z = 8, N = 16). Predictions within the shell model calculation for the 23,24O ground state have been confirmed measuring their spectroscopic factors. Results obtained in one-neutron removal reactions performed by using in-flight radioactive ion beams produced at the Fragment Separator FRS of GSI are reported. [ABSTRACT FROM AUTHOR]

The two-proton radioactivity of the previously unknown 19Mg ground-state is observed by tracking the decay products in-flight. The trajectories of the 2p-decay products, 17Ne+p+p, have been measured by using tracking micro-strip detectors which allowed to reconstruct the 2p-decay vertices and fragment correlations. The half-life of 19Mg deduced from the measured vertex distribution is 4.0(15) ps in the system of 19Mg. The Q-value of the 2p-decay of the 19Mg ground-state inferred from the measured p-p-17Ne correlations is 0.75(5) MeV. [ABSTRACT FROM AUTHOR]

Heavy neutron-rich nuclei close to the neutron closed shell N = 126 were produced by fragmentation of a 1 A GeV 208Pb beam in a beryllium target at the Fragment Separator at GSI. Around 30 heavy neutron-rich isotopes have been synthesized for the first time and the half-lives of some of them have been determined. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

One-nucleon removal reactions at relativistic energies have been used as spectroscopic tool to obtain information about the ground state properties of several neutron-rich isotopes in the sd-shell. Using the FRS at GSI, the longitudinal momentum distributions of the emerging fragments after one-nucleon removal cross-sections were measured. The relative contributions of the remaining fragments in their ground and excited states have been determined from measurements of γ rays in coincidence with the longitudinal momentum distributions. The interesting case of 23O will be directly address. The interpretation of our experimental results in the framework of a simple theoretical model will favours a spin and parity assignment of 1/2+ for the 23O ground state in agreement with shell model predictions. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

The ground state structure of the near drip-line 23O nucleus and neutron-rich 17,21O isotopes has been investigated at GSI via exclusive measurements of one-neutron Coulomb breakup reactions with a Pb target using secondary beams of the corresponding projectiles at 400–600 MeV/u. Differential cross sections for electromagnetic dissociation have been measured and compared with the calculated ones in a direct breakup model. The cross section dσ/dE* (excitation energy E*), further differentiated according to the observed (excited) states of the remaining nucleus, provides spectroscopic information on the ground state of these nuclei. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

One-nucleon removal reactions at relativistic energies have been used as spectroscopic tool to obtain information about the ground state properties of [sup 8]B and [sup 23]O. Using the FRS at GSI, the longitudinal momentum distributions of the emerging fragments after breakup and the one-nucleon removal cross-sections were measured. The relative contributions of the remaining fragments ([sup 7]Be and [sup 22]O) in their ground and excited states have been determined from measurements of γ rays in coincidence with the longitudinal momentum distributions. In the [sup 8]B case, the experimental breakup data on two different targets (C and Pb) allow a determination of the weight of the [sup 7]Be[sup *] component in the [sup 8]B ground state wave function as (13.3±2.2) %. These results are discussed in the context of a theoretical three-body model. Preliminary results on [sup 23]O indicate a spin and parity assignment of ½[sup +] in agreement with shell model predictions. [ABSTRACT FROM AUTHOR]

Using the very precise value of the baryonic density of the Universe recently obtained by WMAP, Big Bang Nucleosynthesis calculations predict a primordial 7Li abundance which is a factor 2 – 3 higher than that observed in galactic halo dwarf stars. Up to now, the role of the 7Be(d,p)2α reaction has been neglected. We have studied this reaction, for the first time at energies appropriate to the Big Bang environment, at the CYCLONE facility at Louvain-la-Neuve using a radioactive 7Be beam. The experimental set-up is briefly described. Results and consequences for primordial nucleosythensis are discussed. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

The 26Al nucleus has a shorter life-time than the Universe showing that the nucleosynthesis of this element might be an ongoing process in stars. The reaction 26Si(p,γ)27 P competes with the production of 26Al. Coulomb dissociation of 27 P is an indirect method to measure that reaction. An experiment was performed at GSI with a 36Ar primary beam at 500 MeV to measure this reaction. [ABSTRACT FROM AUTHOR]