Evidence of the QCD Tricritical Endpoint Existence at NICA-FAIR Energies

Abstract

We present a summary of possible signals of the chiral symmetry restoration and deconfinement phase transitions which may be, respectively, probed at the center of mass collision energies at 4.3-4.9 GeV and above 8.7-9.2 GeV. It is argued that these signals may evidence for an existence of the tricritical endpoint of QCD phase diagram at the collision energy around 8.7-9.2 GeV. The equation of state hadronic matter with the restored chiral symmetry is discussed and the number of bosonic and fermionic degrees of freedom is found.

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