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arXiv · 0911.3510

Thermodynamics of a three-flavor nonlocal Polyakov--Nambu--Jona-Lasinio model

Abstract

The present work generalizes a nonlocal version of the Polyakov loop-extended Nambu and Jona-Lasinio (PNJL) model to the case of three active quark flavors, with inclusion of the axial U(1) anomaly. Gluon dynamics is incorporated through a gluonic background field, expressed in terms of the Polyakov loop. The thermodynamics of the nonlocal PNJL model accounts for both chiral and deconfinement transitions. Our results obtained in mean-field approximation are compared to lattice QCD results for $N_\text{f}=2+1$ quark flavors. Additional pionic and kaonic contributions to the pressure are calculated in random phase approximation. Finally, this nonlocal 3-flavor PNJL model is applied to the finite density region of the QCD phase diagram. It is confirmed that the existence and location of a critical point in this phase diagram depends sensitively on the strength of the axial U(1) breaking interaction.

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T. Hell, S. Rößner, M. Cristoforetti, W. Weise. 2009-11-18. Thermodynamics of a three-flavor nonlocal Polyakov--Nambu--Jona-Lasinio model. https://doi.org/10.1103/physrevd.81.074034

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