A. Grzeszczuk - Academia.edu (original) (raw)

Papers by A. Grzeszczuk

International Journal of Modern Physics E, 2010

... di Fisica e Astronomia, Università di Catania, Via S.Sofia 95123 Catania, Italy MB CHATTERJEE... more ... di Fisica e Astronomia, Università di Catania, Via S.Sofia 95123 Catania, Italy MB CHATTERJEE Saha Institute of Nuclear Physics, Kolkata, India E. DE FILIPPO INFN - Sezione di Catania, Via S.Sofia 95123 Catania, Italy E. GERACI INFN - Sezione di Catania, Via S.Sofia ...

ABSTRACT The angular distributions and energy spectra of light charged particles from the 28Si+α ... more ABSTRACT The angular distributions and energy spectra of light charged particles from the 28Si+α reaction have been measured at Eα = 26 MeV. The particle evaporation spectra and the angular distributions for transitions to excited states of residual nuclei were analyzed with the Hauser-Feshbach compound-nucleus model and finite-range DWBA. The two- und three-nucleon spectroscopic factors have been obtained.

Acta Physica Polonica B - ACTA PHYS POL B, 2009

For fragments emitted in the reactions 124Sn + 64Ni and 112Sn + 58Ni at 35 AMeV, isotopic composi... more For fragments emitted in the reactions 124Sn + 64Ni and 112Sn + 58Ni at 35 AMeV, isotopic composition and velocity correlations have been studied as a function of the centrality of the collision, using the 4pi Chimera multidetector. We have investigated the time scale for fragments formation, in order to distinguish between prompt dynamical and sequential statistical emission. Promptly emitted light fragments (Z leq 9) produced in the mid-rapidity domain are characterised by larger N/Z ratio and stronger angular anisotropies than those produced in sequential statistical emission. Results are compared with stochastic BNV code simulations obtained for primary fragments. Valuable information on the symmetry term of the nuclear equation of state at sub-saturation densities are obtained.

Physical Review Letters, 2009

40 Ca+ 40,48 Ca, 46 Ti reactions at 25 MeV/A have been studied using the 4π CHIMERA detector. An ... more 40 Ca+ 40,48 Ca, 46 Ti reactions at 25 MeV/A have been studied using the 4π CHIMERA detector. An isospin effect on the competition between incomplete fusion and dissipative binary reaction mechanisms has been observed. The probability of producing a compound system is observed to be lower in the case of N≈Z colliding systems as compared to the case of reactions induced on the more neutron rich 48 Ca target. Predictions based on CoMD-II calculations show that the competition between fusion-like and dissipative reactions, for the selected centrality, can strongly constraint the parameterization of symmetry energy and its density dependence in the nuclear equation of state.

Nuclear Physics A, 2004

The new detector CHIMERA, in its final 47r configuration, has been installed at Laboratori Nazion... more The new detector CHIMERA, in its final 47r configuration, has been installed at Laboratori Nazionali de1 Sud (LNS) in Catania in January 2003. Beams of different energies ranging from protons to Au ions were delivered by the Tandem and the Super Conducting Cyclotron for nuclear reaction studies, in agreement with the approval of the Scientific Advisory Committee of LNS. Recent experimental results confirm very low energy thresholds of the trigger (below 0.5 MeV/nucleon), ensured within a wide dynamical range. Good characteristics of identification of light charged particles and heavy fragments have been obtained by using three detection techniques: AE-E, A&time of flight, and the Pulse-Shape discrimination method. We present results of recent analysis concerning the production of intermediate mass fragments (IMF) in semi-peripheral collisions. Our results combined with theoretical Boltzmann-Nordheim-Vlasov simulations clearly demonstrate the presence of very fast processes of IMF production in the overlapping region of the target and projectile nuclei during re-separation, i.e. in the time scale comparable with the collision time. Evidence for slower, sequential-like production of IMF's is also shown.

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2002

... h INFN, Sezione di Bologna and Dip. di Fisica Universitá di Bologna, Italy. i Laboratori Nazi... more ... h INFN, Sezione di Bologna and Dip. di Fisica Universitá di Bologna, Italy. i Laboratori Nazionali del Sud, INFN, Sezione di Catania, Via S. Sofia 44, I-95123, Catania, Italy. j Dip. di Fisica e astronomia dell&#x27;Universitá di Catania, Catania, Italy. k DAPNIA-SPhN, CEA Saclay, France ...

At LNS are available radioactive beams at tandem and intermediate energies provided respectively ... more At LNS are available radioactive beams at tandem and intermediate energies provided respectively by the EXCYT and by the fragmentation FRIBS facilities. Using these beams, and the 4pi detector CHIMERA, we want to study excitation and decay of resonances in light exotic nuclei populated with pick-up stripping and other reaction mechanisms. Some preliminary results obtained with stable and unstable beams are reported.

Journal of Physics G: Nuclear and Particle Physics, 1994

The 29,30Si( alpha ; alpha 0, alpha ') and 30Si( alpha , t) reactions have been studied a... more The 29,30Si( alpha ; alpha 0, alpha ') and 30Si( alpha , t) reactions have been studied at a beam energy of 26.6 MeV. The data have been analysed assuming a presence of direct and compound reaction mechanisms. Angular distributions have been calculated using coupled channels or DWBA and Hauser-Feshbach model approaches. For the inelastic excitations quadrupole deformation parameters were