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arXiv · 1005.0910

QCD phase diagram at finite baryon and isospin chemical potentials

Abstract

The phase structure of two-flavor QCD is explored for thermal systems with finite baryon- and isospin-chemical potentials, mu_B and mu_{iso}, by using the Polyakov-loop extended Nambu--Jona-Lasinio (PNJL) model. The PNJL model with the scalar-type eight-quark interaction can reproduce lattice QCD data at not only mu_{iso}=mu_B=0 but also mu_{iso}>0 and mu_B=0. In the mu_{iso}-mu_{B}-T space, where T is temperature, the critical endpoint of the chiral phase transition in the mu_B-T plane at mu_{iso}=0 moves to the tricritical point of the pion-superfluidity phase transition in the mu_{iso}-T plane at mu_B=0 as mu_{iso} increases. The thermodynamics at small T is controlled by sqrt{sigma^2+pi^2} defined by the chiral and pion condensates, sigma and pi.

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Takahiro Sasaki, Yuji Sakai, Hiroaki Kouno, Masanobu Yahiro. 2010-12-16. QCD phase diagram at finite baryon and isospin chemical potentials. https://doi.org/10.1103/physrevd.82.116004

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