New Understanding of the Phase Diagram of QCD
DOI:
https://doi.org/10.15407/ujpe71.2.166Keywords:
phase diagram of QCD, Nc methods, baryon density, spectrum of mesons and glueballsAbstract
The phase diagram of QCD at finite temperature is understood using large Nc methods. For zero baryon density and for temperatures below T ≤ 160 MeV, the three-dimensional string model is shown to describe the thermodynamics of QCD, as well as the spectrum of mesons and glueballs in vacuum. This description involves no undetermined parameters. It is argued that there are at least three phases at zero baryon number density characterized by the Nc dependence of extensive thermodynamic quantities. At high baryon number density and low temperature, there are again three phases. One of these phases, the quarkyonic phase, with energy density of order Nc, is distinguished from its counterpart at low baryon density and temperature by its chiral properties.
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