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arXiv · 1307.2184

Functional renormalization group study of the two-flavor linear sigma model in the presence of the axial anomaly

Mara Grahl·Dirk H. Rischke
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Abstract

The $SU(2)_A \times U(2)_V$-symmetric chiral linear sigma model in the presence of the axial anomaly is studied in the local-potential approximation of the Functional Renormalization Group (FRG). The renormalization group (RG) flow is investigated in a truncation which reproduces recent results for the $U(2)_A \times U(2)_V$-symmetric model in the limit of vanishing axial anomaly strength. We search for the conjectured O(4) fixed point in the presence of the $U(1)_A$ anomaly and analyze its stability properties.

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Mara Grahl, Dirk H. Rischke. 2014-10-03. Functional renormalization group study of the two-flavor linear sigma model in the presence of the axial anomaly. https://doi.org/10.1103/physrevd.88.056014

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