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arXiv · hep-lat/9807018

Anomalous Chiral Symmetry Breaking above the QCD Phase Transition

Shailesh Chandrasekharan·Dong Chen·Norman Christ·Weonjong Lee·Robert Mawhinney·Pavlos Vranas
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Abstract

We study the anomalous breaking of U_A(1) symmetry just above the QCD phase transition for zero and two flavors of quarks, using a staggered fermion, lattice discretization. The properties of the QCD phase transition are expected to depend on the degree of U_A(1) symmetry breaking in the transition region. For the physical case of two flavors, we carry out extensive simulations on a 16^3 x 4 lattice, measuring a difference in susceptibilities which is sensitive to U_A(1) symmetry and which avoids many of the staggered fermion discretization difficulties. The results suggest that anomalous effects are at or below the 15% level.

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Shailesh Chandrasekharan, Dong Chen, Norman Christ, Weonjong Lee, Robert Mawhinney, Pavlos Vranas. 1998-07-08. Anomalous Chiral Symmetry Breaking above the QCD Phase Transition. https://doi.org/10.1103/physrevlett.82.2463

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