An Infrared Fixed Point and Renormalizabilitiy of 2-Dim. O(4) Nonlinear σ-Model with Wess-Zumino Term
We study a quantum stability of O(4) nonlinear σ-model with the Wess-Zumino term. Deriving a Ward-Takahashi identity, we show the renormalizability of this model and prove that a particular value of the coupling constant λ2=2π/k stays unchanged even after quantum corrections are included. As a complementary check we have calculated a one-loop divergent part of the effective action.