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Directed Flow of Baryons in Heavy-Ion Collisions

Yu. B. Ivanov·E. G. Nikonov·W. Noerenberg·A. A. Shanenko·V. D. Toneev
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Abstract

The collective motion of nucleons from high-energy heavy-ion collisions is analyzed within a relativistic two-fluid model for different equations of state (EoS). As function of beam energy the theoretical slope parameter F_y of the differential directed flow is in good agreement with experimental data, when calculated for the QCD-consistent EoS described by the statistical mixed-phase model. Within this model, which takes the deconfinement phase transition into account, the excitation function of the directed flow turns out to be a smooth function in the whole range from SIS till SPS energies. This function is close to that for pure hadronic EoS and exhibits no minimum predicted earlier for a two-phase bag-model EoS. Attention is also called to a possible formation of nucleon antiflow (F_y < 0) at energies of the order of 100 A GeV.

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Yu. B. Ivanov, E. G. Nikonov, W. Noerenberg, A. A. Shanenko, V. D. Toneev. 2000-11-01. Directed Flow of Baryons in Heavy-Ion Collisions. https://arxiv.org/abs/nucl-th/0011004

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