A new technique of large-area thin ion implanted silicon detectors has been developed within the R&D performed by the FAZIA Collaboration. The essence of the technique is the application of a ...low-temperature baking process instead of high-temperature annealing. This thermal treatment is performed after B
+
ion implantation and Al evaporation of detector contacts, made by using a single adjusted Al mask. Extremely thin silicon pads can be therefore obtained. The thickness distribution along the
X
and
Y
directions was measured for a prototype chip by the energy loss of
α
-particles from
241
Am (〈
E
α
〉 = 5.5 MeV). Preliminary tests on the first thin detector (area ≈ 20 × 20 mm
2
) were performed at the INFN-LNS cyclotron in Catania (Italy) using products emitted in the heavy-ion reaction
84
Kr (
E
= 35
A
MeV) +
112
Sn. The
ΔE
−
E
ion identification plot was obtained using a telescope consisting of our thin
ΔE
detector (21
μ
m thick) followed by a typical FAZIA 510
μ
m E detector of the same active area. The charge distribution of measured ions is presented together with a quantitative evaluation of the quality of the
Z
resolution. The threshold is lower than 2
A
MeV depending on the ion charge.
The BRAHMS probes the hot and dense nuclear matter at the RHIC which has reached its design
energy of psNN = 200 GeV for Au + Au collisions. The BRAHMS uses magnetic spectrometers
for hadrons ...covering a large phase space 0 < y < 4 with good particle identification and momentum
resolution. A comprehensive investigation of multiplicity distributions of emitted charged particles
is carried out. Ratios of yields of antiparticles to particles are also measured as a function of rapidity.
Rapidity dependent net-proton yield indicates that substantial transparency has been achieved in
these collisions. Transverse momentum spectra of charged hadrons are measured up to 5 GeV/c
which indicates a significant medium eect when compared to nucleon + nucleon reference spectra. KCI Citation Count: 3
The elliptic-flow ratio of neutrons with respect to protons or light complex particles in reactions of heavy ions at pre-relativistic energies has been proposed as an observable sensitive to the ...strength of the symmetry term of the nuclear equation of state at supra-saturation densities. In the ASY-EOS experiment at the GSI laboratory, flows of neutrons and light charged particles were measured for 197Au+197Au, 96Zr+96Zr and 96Ru+96Ru collisions at 400 MeV/nucleon with the Large Area Neutron Detector LAND as part of a setup with several additional detection systems used for the event characterization. Flow results obtained for the Au+Au system, in comparison with predictions of the UrQMD transport model, confirm the moderately soft to linear density dependence of the symmetry energy deduced from the earlier FOPI-LAND data.
The elliptic-flow ratio of neutrons with respect to protons or light complex particles in reactions of heavy-ions at pre-relativistic energies has been proposed as an observable sensitive to the ...strength of the symmetry term of the nuclear equation of state at supra-saturation densities. The results obtained from the existing FOPI/LAND data for super(197)Au+ super(197)Au collisions at 400 MeV/nucleon in comparison with the UrQMD model simulations favoured a moderately soft symmetry term, but suffer from a considerable statistical uncertainty. These results have been confirmed by an independent analysis based on the Tubingen QMD simulations. In order to obtain an improved data set for Au+Au collisions and to extend the study to other systems, a new experiment was carried out at the GSI laboratory by the ASY-EOS collaboration. The present status of the data analysis is reported
The properties of the multifragmentation of ``hot sources'' produced in the 40Ca +40Ca reaction have been studied at a beam energy 35 MeV/nucleon. Two signatures of prompt multifragmentation, which ...make use of special features of particle emission from the ``freeze out volume'', together with an analysis of the reduced relative velocity between pairs of intermediate mass fragments, indicate the presence of a transition from sequential decay to prompt multifragmentation at an excitation energy of about 3 MeV/nucleon.
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