G. Nebbia

Experimental determination of the symmetry energy of a low density nuclear gas

Experimental analyses of moderate-temperature nuclear gases produced in the violent collisions of 35 MeV/nucleon Zn-64 projectiles with Mo-92 and Au-197 target nuclei reveal a large degree of alpha particle clustering at low densities. For these gases, temperature- and density-dependent symmetry energy coefficients have been derived from isoscaling analyses of the yields of nuclei with A <= 4. At densities of 0.01 to 0.05 times the ground-state density of symmetric nuclear matter, the temperature- and density-dependent symmetry energies range from 9.03 to 13.6 MeV. This is much larger than those obtained in mean-field calculations and reflects the clusterization of low-density nuclear matter. The results are in quite reasonable agreement with calculated values obtained with a recently proposed virial equation of state calculation.

The EXPLODET project: advanced nuclear techniques for humanitarian demining

Thermal neutron activation and fast neutron scattering are known to be a useful tool to detect hidden explosives which present an elevated concentration of nitrogen and peculiar elemental ratio for light elements (C, N, O). Such characteristics can be suitably optimized to detect the small amount of explosives contained in anti-personnel mines (APM) disseminated in former war theatres. We report here on a research program aimed at defining a conceptual design of a field operated system for APM detection based on neutron induced reactions. ( 1999 Elsevier Science B.V. All rights reserved.

Laboratory Tests of Low Density Astrophysical Nuclear Equations of State

Clustering in low density nuclear matter has been investigated using the NIMROD multidetector at Texas A&M University. Thermal coalescence modes were employed to extract densities, ρ, and temperatures, T, for evolving systems formed in collisions of 47A MeV (40)Ar+(112)Sn, (124)Sn and (64)Zn+(112)Sn, (124)Sn. The yields of d, t, (3)He, and (4)He have been determined at ρ=0.002 to 0.03 nucleons/fm(3) and T=5 to 11 MeV. The experimentally derived equilibrium constants for α particle production are compared with those predicted by a number of astrophysical equations of state. The data provide important new constraints on the model calculations.

Critical behavior in light nuclear systems: Experimental aspects

An extensive experimental survey of the features of the disassembly of a small quasi-projectile system with

Reaction dynamics and multifragmentation in Fermi energy heavy ion reactions

A \sim

Determination of the temperatures of hot nuclei from “first chance” emission spectra

36, produced in the reactions of 47 MeV/nucleon

Investigation of the 40Ar + 197Au, 238U systems at 44 MeV/u

^{40}

Linear momentum transfer investigated in the 20Ne + 197Au and 209Bi systems at 30 MeV/u

Ar +

Light output of EJ228 scintillation neutron detectors.

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Nuclear matter symmetry energy at 0.03(ρ/ρ0)0.2

Al,