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arXiv · 0706.3549

On the existence of the critical point in finite density lattice QCD

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 $μ_q/T \simge 2.5$. We also discuss the difference between the phase structures of QCD with non-zero quark chemical potential and non-zero isospin chemical potential.

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Shinji Ejiri. 2007-12-11. On the existence of the critical point in finite density lattice QCD. https://doi.org/10.1103/physrevd.77.014508

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