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Pion and Strangeness Production as Signals of QCD Phase Transition

Marek Gazdzicki
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Abstract

It is shown that data on pion and strangeness production in central nucleus-nucleus collisions are consistent with the hypothesis of a Quark Gluon Plasma formation between 15 A GeV/c (BNL AGS) and 160 A GeV/c (CERN SPS) collision energies. The experimental results interpreted in the framework of a statistical approach indicate that the effective number of degrees of freedom increases by a factor of about 3 in the course of the phase transition and that the plasma created at CERN SPS energy may have a temperature of about 280 MeV (energy density $\approx$ 10 GeV/fm^3). Experimental studies of central Pb+Pb collisions in the energy range 20-160 A GeV/c are urgently needed in order to localize the threshold energy, and study the properties of the QCD phase transition.

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Marek Gazdzicki. 1997-02-19. Pion and Strangeness Production as Signals of QCD Phase Transition. https://arxiv.org/abs/nucl-th/9701050

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