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Chiral phase transition at high temperature and density in the QCD-like theory

O. Kiriyama·M. Maruyama·F. Takagi
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Abstract

The chiral phase transition at finite temperature T and/or chemical potential $μ$ is studied using the QCD-like theory with a variational approach. The ``QCD-like theory'' means the improved ladder approximation with an infrared cutoff in terms of a modified running coupling. The form of Cornwall-Jackiw-Tomboulis effective potential is modified by the use of the Schwinger-Dyson equation for generally nonzero current quark mass. We then calculate the effective potential at finite T and/or $μ$ and investigate the phase structure in the chiral limit. We have a second-order phase transition at $T_c=129$ MeV for $μ=0$ and a first-order one at $μ_c=422$ MeV for T=0. A tricritical point in the T-$μ$ plane is found at T=107 MeV, $μ=210$ MeV. The position is close to that of the random matrix model and some version of the Nambu-Jona-Lasinio model.

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O. Kiriyama, M. Maruyama, F. Takagi. 2000-08-09. Chiral phase transition at high temperature and density in the QCD-like theory. https://doi.org/10.1103/physrevd.62.105008

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