P. Guazzoni | Università degli Studi di Milano - State University of Milan (Italy) (original) (raw)

Papers by P. Guazzoni

Physical Review C, 2010

An interesting process of violent reseparation of a heavy nuclear system into three or four fragm... more An interesting process of violent reseparation of a heavy nuclear system into three or four fragments of comparable size was recently observed in 197 Au + 197 Au collisions at 15 MeV/nucleon. Combined analysis of the binary deep inelastic events and the ternary and quaternary breakup events demonstrates that the newly observed ternary and quaternary reactions belong to the same wide class of deep inelastic collisions as the conventional (binary) damped reactions. It is shown that the ternary and quaternary breakup reactions occur at extremely inelastic collisions corresponding to small impact parameters, while more peripheral collisions lead to well-known binary deep inelastic reactions. PACS number(s): 25.70.Lm, 25.70.Mn In a Letter [1], followed by a regular article [2], we reported on the observation of a new reaction mode in reseparation of a very heavy nuclear system in 197 Au + 197 Au collisions at 15 MeV/nucleon. In an exclusive-type experiment it was demonstrated that, in addition to the binary (deep inelastic) reaction mode, the colliding system shows a rather exotic process of violent reseparation into three or four massive fragments, nearly aligned along a common reseparation axis. From the systematic effect of the deflection of fragments from the reseparation axis, a very short time scale of the breakup process, not exceeding 100 fm/c, was estimated in Refs.

International Journal of Modern Physics E-Nuclear Physics, 2006

... Abstract | Full Text (PDF, 411KB) | References. Title: DYNAMICAL FISSION IN THE Sn + Ni INTER... more ... Abstract | Full Text (PDF, 411KB) | References. Title: DYNAMICAL FISSION IN THE Sn + Ni INTERACTION AT 35A MeV. Author(s): P. RUSSOTTO Present address: INFN Laboratori Nazionali Del Sud, Via Santa Sofia 62 I Catania, 95123, Italy. INFN Lab. Naz. del Sud and Dip. ...

Proceedings. 24th EUROMICRO Conference (Cat. No.98EX204), 1998

The paper deals with the evaluation of the real-time behavior of a proposed kind of computing sys... more The paper deals with the evaluation of the real-time behavior of a proposed kind of computing system for monitoring and controlling multidetector arrays used in nuclear physics experiments. The system was implemented by extending a previous monoprocessor system in a multiprocessing environment, based on ADSP-21060-SHARC digital signal processors. The proposed system is being developed within the CHIMERA multidetector project

IEEE Nuclear Science Symposium Conference Record, 2005, 2005

ABSTRACT The problem considered in this work is the classification of the reaction products. The ... more ABSTRACT The problem considered in this work is the classification of the reaction products. The assumption made herein is that the shape of the pulse (which height corresponds to the energy lost by the reaction product) is the impulse response of a dynamic linear system and contains complete information on the ion. In this case the product classification can be done by pulse-shape analysis. The present contribution proposes a complete procedure for isotopic identification of light charged particles stopped in the CsI(Tl) scintillators. The main idea is to use the cascade of a state-space identification algorithm and a parametric non-linear map using the model parameters as input regressors. The algorithm has been tested on a large set of impulse-responses, and provides a fully-automatic accurate classification of the isotopes.

Physical Review C, 2005

The 123Sb(p-->,alpha)120Sn reaction has been studied in a high resolution measurement at incid... more The 123Sb(p-->,alpha)120Sn reaction has been studied in a high resolution measurement at incident energy of 24 MeV using a polarized proton source and a Q3D spectrometer. The differential cross sections and asymmetries for transitions to levels of 120Sn homologous to the lowest energy states of 119In have been measured and interpreted in terms of the experimental differential cross sections and asymmetries of the parent 119In states, on the basis of the weak-coupling model. Several (17) states of the 120Sn residual nucleus, not previously reported in the literature, have been detected and spins and parities have been proposed for seven of them, while parities have been proposed for five other previously known levels. In order to analyze the transitions populating the homologous levels, for both differential cross sections and asymmetries, microscopic DWBA calculations have been performed using spectroscopic amplitudes obtained from a shell-model study.

Physical Review C, 2008

ABSTRACT Cross-section angular distributions of 38 (p, t) transitions to final states of Sn118 up... more ABSTRACT Cross-section angular distributions of 38 (p, t) transitions to final states of Sn118 up to an excitation energy of 3.597 MeV have been measured in a high-resolution experiment at an incident proton energy of 21 MeV. A distorted-wave Born approximation (DWBA) analysis of the 38 experimental differential cross sections, carried out by using conventional Woods-Saxon potentials, allowed us either 18 confirmations of previous spin and parity values or new assignments of spin and parity to 14 states of Sn118. A shell-model calculation has been performed by using a realistic two-body effective interaction derived from the CD-Bonn nucleon-nucleon potential. The doubly-magic nucleus Sn132 is assumed as a closed core, with 14 valence neutron holes occupying the five levels of the 50-82 shell. Within this model space the calculations are performed by employing the seniority scheme including states with seniority up to 4. The energy spectrum of Sn118 has been calculated and compared with the experimental one. The theoretical two-neutron spectroscopic amplitudes are used in the microscopic DWBA calculations of some cross-section angular distributions.

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.

Czechoslovak Journal of Physics, 2002

... I ~L ]- 9 6" ! ' 2" t 4,- ~. ~ r ".r ' ~tt &... more ... I ~L ]- 9 6" ! ' 2" t 4,- ~. ~ r ".r ' ~tt " |- ~ 1-5-|- 1112" 7/,.}" 512 § 2.0 1.0 - - 312 + - - i12* 0.0 t ~.12+~ - - o" o" 0.0 zOe, pb ZOSTl Shell Model Fig. ... A356 (1997) 381. [4] JN Gu, A. Vitturi, CH Zhang, P. Guazzoni, L. Zetta, G. Craw, M. Jaskola, G. Staudt: Phys. Rev. C55 (1997) 2395. ...

2006 IEEE Nuclear Science Symposium Conference Record, 2006

We applied the digital pulse shape acquisition to the read out of the anode pads of the Focal Pla... more We applied the digital pulse shape acquisition to the read out of the anode pads of the Focal Plane Detector of the MAGNEX spectrometer in order to measure the position coordinates using digital signal processing.