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arXiv · 1910.05477

New Insight about the Effective Restoration of U_A(1) Symmetry

Xiang Li·Wei-jie Fu·Yu-xin Liu
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Abstract

The effective restoration of the U_{A}(1) symmetry is revisited by implementing the functional renormalization group approach combining with the 2+1 flavor Polyakov-loop quark-meson model. A temperature-dependent 't Hooft term is taken to imitate the restoration of the U_{A}(1) symmetry. Order parameters, meson spectrum and mixing angles, especially the pressure and the entropy density of the system are calculated to explore the effects of different U_{A}(1) symmetry restoration patterns. We show then that the temperature for the restoration of the U_{A}(1) symmetry is much higher than that for the chiral symmetry SU_{A}(3).

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Xiang Li, Wei-jie Fu, Yu-xin Liu. 2019-10-12. New Insight about the Effective Restoration of U_A(1) Symmetry. https://doi.org/10.1103/physrevd.101.054034

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