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arXiv · 1505.06799

Topological feature and phase structure of QCD at complex chemical potential

Kouji Kashiwa·Akira Ohnishi
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Abstract

The pseudo-critical temperature of the confinement-deconfinement transition and the phase transition surface are investigated by using the complex chemical potential. We can interpret the imaginary chemical potential as the Aharonov-Bohm phase, then the analogy of the topological order suggests that the Roberge-Weiss endpoint would define the pseudo-critical temperature. The behavior of the Roberge-Weiss endpoint at small real quark chemical potential is investigated with the perturbative expansion. The expected QCD phase diagram at complex chemical potential is presented.

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Kouji Kashiwa, Akira Ohnishi. 2015-10-06. Topological feature and phase structure of QCD at complex chemical potential. https://doi.org/10.1016/j.physletb.2015.09.036

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