A detailed knowledge of the decay properties of the so called Hoyle state in the 12C nucleus (Ex=7.654 MeV, 0+) is required to calculate the rate at which carbon is forged in typical red-giant stars. ...This paper reports on a new almost background-free measurement of the radiative decay branching ratio of the Hoyle state using advanced charged particle coincidence techniques. The exploitation, for the first time in a similar experiment, of a bidimensional map of the coincidence efficiency allows to reach an unitary value and, consequently, to strongly reduce sources of systematic uncertainties. The present results suggest a value of the radiative branching ratio of Γrad/Γtot=4.4(6)·10-4. This finding helps to resolve the tension between recent data published in the literature.
The FAZIA apparatus exploits Pulse Shape Analysis (PSA) to identify nuclear fragments stopped in the first layer of a Silicon-Silicon-CsI(Tl) detector telescope. In this work, for the first time, we ...show that the isotopes of fragments having atomic number as high as Z∼20 can be identified. Such a remarkable result has been obtained thanks to a careful construction of the Si detectors and to the use of low noise and high performance digitizing electronics. Moreover, optimized PSA algorithms are needed. This work deals with the choice of the best algorithm for PSA of current signals. A smoothing spline algorithm is demonstrated to give optimal results without requiring too much computational resources.
Abstract A systematic analysis of the data obtained by the FAZIA collaboration during a recent experiment with a neutron rich projectile is presented. The main goal was to compare the experimental ...results with the HIPSE event generator simulations to investigate the influence of the neutron rich entrance channel on the quasi-projectile fragment properties. The full isotopic range of charged particles detected in this experiment was within the limit of the resolution of the FAZIA detector. A majority of quasi-projectile fragments were detected thanks to the forward angular acceptance of the experimental setup which was confirmed through the HIPSE calculations. Essentially, the lowering of N / Z of quasi-projectile fragments with the beam energy was found to be present since the initial phase of the reaction. Thus, pre-equilibrium neutron emissions might be a possible candidate to explain such an effect.
A systematic analysis of the data obtained by the FAZIA collaboration during a recent experiment with a neutron rich projectile is presented. The main goal was to compare the experimental results ...with the HIPSE event generator simulations to investigate the influence of the neutron rich entrance channel on the quasi-projectile fragment properties. The full isotopic range of charged particles detected in this experiment was within the limit of the resolution of the FAZIA detector. A majority of quasi-projectile fragments were detected thanks to the forward angular acceptance of the experimental setup which was confirmed through the HIPSE calculations. Essentially, the lowering of
N
/
Z
of quasi-projectile fragments with the beam energy was found to be present since the initial phase of the reaction. Thus, pre-equilibrium neutron emissions might be a possible candidate to explain such an effect.
Abstract
The onset of Multifragmentation phenomenon is investigated at low excitation energies. A detailed study on the origin of Intermediate Mass Fragment (IMF, Z>=3) produced in central collisions ...in the
58
Ni+
40
Ca reaction at 25 AMeV is presented. The experimental campaign was performed with CHIMERA multi-detector at INFN Laboratori Nazionali del Sud in Catania (Italy). The multiple identification techniques of the 4p apparatus, together with low detection thresholds, enable the performance of a careful selection of Fusion-evaporation residues, Multifragmentation sources and their decay products. Comparisons with dynamical approach based on Boltzmann-Langevin-One-Body (BLOB) model predictions coupled with sequential emission code, were used as useful tools to depict and understand the characteristics of fragments emitted from an equilibrated compound nucleus or formed simultaneously in the multifragmenting source. A comparison with the preliminary results obtained for fragment production in central collisions of the same system,
58
Ni+
40
Ca, at higher incident energies E
beam
=35AMeV, allows to study and characterize the evolution of multifragmentation phenomenon at the lower end of Fermi energies.
Abstract
The recently coupled INDRA-FAZIA apparatus offers unique opportunities to investigate heavy ion collisions at Fermi energies by combining the optimal identification capabilities of FAZIA and ...the large angular coverage of INDRA. We present a selection of the results of the analysis of the first experimental campaign performed with INDRA-FAZIA, in which the four reactions
58,64
Ni+
58,64
Ni have been studied at two different beam energies (32 and 52 MeV/nucleon) in the intermediate energy regime. The present work is focused on the isospin diffusion effects in semiperipheral and peripheral collisions. A stronger isospin equilibration is found at 32 MeV/nucleon than at 52 MeV/nucleon, as expected due to a shorter projectile-target interaction time in the latter case.
An experimental campaign has been performed by the Nuclex-Hector collaboration at the Laboratori Nazionali di Legnaro in order to study different reaction channels by detecting, in coincidence, ...Evaporation Residue (ER), Charged Particles and high energy γ-rays from Giant Dipole Resonance (GDR). The studied system was 48Ti+40Ca at 300, 450 and 600 MeV, using a modular apparatus formed by triplephoswich detectors for ER and particles at the forward angles, the GARFIELD ΔE-E forward drift chamber for the charged particles between 30° and 85° and the HECTOR apparatus at the backward angles for γ-rays.
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