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

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.

19 pages, 2 figures