HOW ABELIAN BRS-SYMMETRY EMERGES IN NONINVARIANT SURROUNDINGS

In a general nonsymmetric renormalizable model with one vector field and one ghost and one antighost we study, if abelian BRS-symmetry can be deduced by postulating renormalizibility and dependence on one interaction coupling. One purpose for analysing this simple model is to clarify the role of the gauge parameter in the course of reduction of couplings. It is shown how the relevant reduction equations, which turn out to be partial differential equations, have to be solved. The perturbative solutions one finds are not only the BRS-invariant ones, but all look like nonlinear gauge fixings and can be related to the BRS-invariant theory in a specific way.