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arXiv · 1104.2142

Imaginary Chemical Potential Approach for the Pseudo-Critical Line in the QCD Phase Diagram with Clover-Improved Wilson Fermions

Keitaro Nagata·Atsushi Nakamura
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Abstract

The QCD phase diagram is studied in the lattice QCD simulation with the imaginary chemical potential approach. We employ a clover-improved Wilson fermion action of two-flavors and a renormalization-group improved gauge action, and perform the simulation at an intermediate quark mass on a $8^3\times 4$ lattice. The QCD phase diagram in the imaginary chemical potential $μ_I$ region is investigated by performing the simulation for more than 150 points on the $(β,μ_I)$ plane. We find that the Roberge-Weiss phase transition at $μ_I/T=π/3$ is first order and its endpoint is second order, which are identified by the phase of the Polyakov loop. We determine the pseudo-critical line from the susceptibility of the Polyakov loop modulus. We find a clear deviation from a linear dependence of the pseudo-critical line on $μ_I^2$.

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Keitaro Nagata, Atsushi Nakamura. 2011-05-16. Imaginary Chemical Potential Approach for the Pseudo-Critical Line in the QCD Phase Diagram with Clover-Improved Wilson Fermions. https://doi.org/10.1103/physrevd.83.114507

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