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arXiv · 0710.0653

Study of the critical point in lattice QCD at high temperature and density

Shinji Ejiri
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Abstract

We propose a method to probe the nature of phase transitions in lattice QCD at finite temperature and density, which is based on the investigation of an effective potential as a function of the average plaquette. We analyze data obtained in a simulation of two-flavor QCD using p4-improved staggered quarks with bare quark mass $m/T = 0.4$, and find that a first order phase transition line appears in the high density regime for $μ_q/T \sim 2.5$. The effective potential as a function of the quark number density is also studied. We calculate the chemical potential as a function of the density from the canonical partition function and discuss the existence of the first order phase transition line.

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Shinji Ejiri. 2007-10-02. Study of the critical point in lattice QCD at high temperature and density. https://arxiv.org/abs/0710.0653

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