Renormalization in Some 2D su(2) Coset Models

We consider a RG flow in certain 2D coset models perturbed by the least relevant field. In the case of the symmetric su(2) coset model we show, up to second order of the perturbation theory, that there exists a nontrivial IR fixed point.We obtain the structure constants and the four-point functions of certain fields by deriving specific recursive relations. This allows us to compute the anomalous dimensions and the mixing coefficients of these fields in the UV and IR theories. In the case of another su(2) coset model, describing the N=2 superconformal theories, we show that there does not exists a nontrivial IR fixed point up to second order.