Centrality and system size dependence of (multi-strange) hyperons at 40$A$ and 158$A$ GeV: A comparison between a binary collision and a Boltzmann + hydrodynamic hybrid model

Abstract

We present results on the centrality and system size dependence of (multi-strange)hyperons in Pb+Pb collisions at 40$A$ and 158$A$ GeV from the Ultra-relativistic Quantum Molecular Dynamics (UrQMD-v2.3) model and a coupled Boltzmann+hydrodynamics calculation. The second approach is realized in a hybrid fashion based on UrQMD with an intermediate hydrodynamical evolution for the hot and dense stage of the collision. This implementation allows a comparison of microscopic transport calculations with hydrodynamic simulations to explore the transition from a system that is not fully equilibrated such as C+C or Si+Si collisions, to a supposedly fully equilibrated system, such as that created in Pb+Pb reactions. The results of our calculation are compared to measurements of the (anti-)hyperon yields at midrapidity ($\mid$y$\mid$ $\le$ 0.5) and total multiplicities performed by the NA49 and NA57 Collaborations at 40$A$ and 158$A$ GeV. Furthermore, we compared our predictions to the centrality dependence of $\Lambda$, $\bar{\Lambda }$ and ${\Xi }^{-}$ rapidity spectra and total multiplicities at 40$A$ and 158$A$ GeV, where possible.

8 pages, 8 figures

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Cited by in corpus (9)

• Hadronization conditions in relativistic nuclear collisions and the QCD pseudo-critical line
• Strange hadron production in heavy ion collisions from SPS to RHIC
• Core-corona separation in the UrQMD hybrid model
• Transport model study of nuclear stopping in heavy ion collisions over an energy range from 0.09A GeV to 160A GeV
• Hybrid model calculations of direct photons in high-energy nuclear collisions
• Phi meson production in In-In collisions at $E_{\mathrm{lab}}$=158$A$ GeV: evidence for relics of a thermal phase
• Recent results on strangeness production from NA49
• Strangeness production in hadronic models and recombination models
• Low mass dimuons within a hybrid approach