(Anti-)strangeness in heavy-ion collisions

FAIRNESS 2016

Moreau, P.^1 ; Cassing, W.^2 ; Palmese, A.^2 ; Bratkovskaya, E.L.^1,3,4

Frankfurt Institute for Advanced Studies, Johann Wolfgang Goethe Universität, Frankfurt am Main, Germany^1

Institut für Theoretische Physik, Universität Gießen, Germany^2

Institut für Theoretische Physik, Johann Wolfgang Goethe Universität, Frankfurt am Main, Germany^3

GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt, Germany^4

关键词: Chiral symmetry restoration;    Deconfinement;    Heavy ion collision;    Light quarks;    Nucleus-nucleus collision;    Reaction dynamics;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/742/1/012016/pdf
DOI  :  10.1088/1742-6596/742/1/012016

来源: IOP

【 摘 要 】

We study the production of hadrons in nucleus-nucleus collisions within the Parton-Hadron-String Dynamics (PHSD) transport approach that is extended to incorporate essentials aspects of chiral symmetry restoration (CSR) in the hadronic sector (via the Schwinger mechanism) on top of the deconfinement phase transition as implemented in PHSD before. The essential impact of CSR is found in the Schwinger mechanism (for string decay) which fixes the ratio of strange to light quark production in the hadronic medium. Our studies suggest a microscopic explanation for the maximum in the K+/π+and ( + Σ0)/π-ratios at about 30 A GeV which only shows up if in addition to CSR a deconfinement transition to partonic degrees-of-freedom is incorporated in the reaction dynamics.