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arXiv · 1309.4598

Remarks on the U(1) axial symmetry and the chiral transition in QCD at finite temperature

E. Meggiolaro·A. Mordà
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Abstract

We discuss the role of the U(1) axial symmetry for the scalar and pseudoscalar meson mass spectrum of QCD at finite temperature, above the chiral transition at T_c, using a chiral effective Lagrangian model, which, in addition to the usual chiral condensate, also includes a (possible) genuine U(1)_A-breaking condensate that (possibly) survives across the chiral transition. The motivations for considering this Lagrangian (and a critical comparison with other effective Lagrangian models existing in the literature) are presented. A detailed comparison between the case N_f=3 (or N_f>3) and the (remarkably different) case N_f=2 is performed. The results obtained in the case N_f=2 are also critically compared with the available lattice results.

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E. Meggiolaro, A. Mordà. 2013-11-28. Remarks on the U(1) axial symmetry and the chiral transition in QCD at finite temperature. https://doi.org/10.1103/physrevd.88.096010

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