Dynamical and statistical fragment emission processes in 200 A MeV Ne-20 + Ar-40 collisions are well probed by measurements of charge (Z), mass (A) and momentum vector ((p) over right arrow) of all ...fragments in large parts of the available momentum space. We present such data obtained at the cluster-jet target of the CELSIUS storage ring, for the first time with an internal, ultra-high vacuum (UHV) compatible detector system (CHICSi). Energy and angular dependence in Z and A distributions are not reproduced by a single-step model, e.g., those based on molecular dynamics (MD), but require a complete three-step model. We use here the intranuclear cascade+ statistical multifragmentation + secondary evaporation model (CFEM). The angular dependence of isobaric ratios, like He-6/Li-6 at low emission velocities and temperatures extracted from isotopic (double) ratios, do exhibit differences, even from this model. These differences, which call for adjustment of model parameters, are discussed. (c) 2005 Elsevier B.V. All rights reserved.
The Giessen Boltzmann-Uehling-Uhlenbeck transport model with relativistic mean fields is used to simulate p-nucleus collisions. Antiproton absorption cross sections and momentum distributions of ...annihilation products are calculated by varying the p coupling strength to the mean meson fields. Parameters of the antiproton-nucleus optical potential are extracted from the comparison of the model calculations with experimental data.
We present experimental results of nuclear-charge changing interactions for 158A-GeV ultrarelativistic In ions in Si, Ge, Sn, W, and Pb targets. Calculations based on the abrasion-ablation model for ...hadronic interaction and the RELDIS model for electromagnetic dissociation are compared to the data.
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