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arXiv · 1312.5149

Chemical freeze-outs of strange and non-strange particles and residual chemical non-equilibrium

K. A. Bugaev·D. R. Oliinychenko·V. V. Sagun·A. I. Ivanytskyi·J. Cleymans·E. G. Nikonov·G. M. Zinovjev
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Abstract

We propose an elaborate version of the hadron resonance gas model with the combined treatment of separate chemical freeze-outs for strange and non-strange hadrons and with an additional γ_{s} factor which accounts for the remaining strange particle non-equilibration. Two sets of chemical freeze-outs parameters are connected by the conservation laws of entropy, baryonic charge, isospin projection and strangeness. The developed approach enables us to perform a high-quality fit of the hadron multiplicity ratios for AGS, SPS and RHIC energies with total χ^2/dof \simeq 1.05. A special attention is paid to a complete description of the Strangeness Horn. A well-known \bar p, \bar Λand \bar Ξselective suppression problem is also discussed.

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K. A. Bugaev, D. R. Oliinychenko, V. V. Sagun, A. I. Ivanytskyi, J. Cleymans, E. G. Nikonov, G. M. Zinovjev. 2013-12-18. Chemical freeze-outs of strange and non-strange particles and residual chemical non-equilibrium. https://arxiv.org/abs/1312.5149

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