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arXiv · 1512.08025

Hadron multiplicities and chemical freeze-out conditions in proton-proton and nucleus-nucleus collisions

V. Vovchenko·V. V. Begun·M. I. Gorenstein
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Abstract

New results of the NA61/SHINE Collaboration at the CERN SPS on mean hadron multiplicities in proton-proton (p+p) interactions are analyzed within the transport models and the hadron resonance gas (HRG) statistical model. The chemical freeze-out parameters in p+p interactions and central Pb+Pb (or Au+Au) collisions are found and compared with each other in the range of the center of mass energy of the nucleon pair $\sqrt{s_{NN}}=3.2-17.3$ GeV. The canonical ensemble formulation of the HRG model is used to describe mean hadron multiplicities in p+p interactions and the grand canonical ensemble in central Pb+Pb and Au+Au collisions. The chemical freeze-out temperatures in p+p interactions are found to be larger than the corresponding temperatures in central nucleus-nucleus collisions.

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V. Vovchenko, V. V. Begun, M. I. Gorenstein. 2016-06-20. Hadron multiplicities and chemical freeze-out conditions in proton-proton and nucleus-nucleus collisions. https://doi.org/10.1103/physrevc.93.064906

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