Four different combinations of 9644Ru and 9640Zr nuclei, both as projectile and target, were investigated at the same bombarding energy of 400A MeV using a 4pi detector. The degree of isospin mixing ...between projectile and target nucleons is mapped across a large portion of the phase space using two different isospin-tracer observables, the number of measured protons and the tritium to 3He yield ratio. The experimental results show that the global equilibrium is not reached even in the most central collisions. Quantitative measures of stopping and mixing are extracted from the data. They are found to exhibit a quite strong sensitivity to the in-medium ( n,n) cross section used in microscopic transport calculations.
Single and double escape peaks are multiplied by appropriate normalization factors and added to the full-energy peak in order to improve its definition relative to the underlying background at the ...high-energy tail of the γ-ray spectrum recorded by a Ge(Li) detector. This procedure is described for the 6728 keV 3 - → O + transition of the 14 C nucleus produced in the 12 C( 18 O, γ) reaction. The advantage of its use is illustrated for the excitation function of this reaction.
The ASY-EOS Experiment at GSI Russotto, P.; Chartier, M.; Cozma, M.D. ...
EPJ Web of Conferences,
01/2016, Volume:
117
Journal Article, Conference Proceeding
Peer reviewed
Open access
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 collisions at 400 MeV/nucleon. 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.
Experimental data on K
+ meson and proton sideward flow measured with the FOPI detector at SIS/GSI in the reactions Ru+Ru at 1.69
A GeV and Ni+Ni at 1.93
A GeV are presented. The K
+ sideward flow is ...found to be anti-correlated (correlated) with the one of protons at low (high) transverse momenta. When compared to the predictions of a transport model, the data favour the existence of an in-medium repulsive K
+-nucleon potential.
Using the large acceptance apparatus FOPI, we study central collisions in the reactions (energies in
A
GeV
are given in parentheses):
40Ca
+
40Ca (0.4, 0.6, 0.8, 1.0, 1.5, 1.93),
58Ni
+
58Ni (0.15, ...0.25, 0.4),
96Ru
+
96Ru (0.4, 1.0, 1.5),
96Zr
+
96Zr (0.4, 1.0, 1.5),
129Xe
+
CsI (0.15, 0.25, 0.4),
197Au
+
197Au (0.09, 0.12, 0.15, 0.25, 0.4, 0.6, 0.8, 1.0, 1.2, 1.5). The observables include cluster multiplicities, longitudinal and transverse rapidity distributions and stopping, and radial flow. The data are compared to earlier data where possible and to transport model simulations.
Collisions of Au on Au at incident energies of 150, 250 and 400
A·MeV were studied with the FOPI-facility at GSI Darmstadt. Nuclear charge (
Z ⩽ 15) and velocity of the products were detected with ...full azimuthal acceptance at laboratory angles 1° ⩽
θlab ⩽ 30°. Isotope separated light charged particles were measured with movable multiple telescopes in an angular range of 6–90°. Central collisions representing about 1% of the reaction cross section were selected by requiring high total transverse energy, but vanishing side flow. The velocity space distributions and yields of the emitted fragments are reported. the data are analysed in terms of a thermal model including radial flow. A comparison with predictions of the quantum molecular model is presented.
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