Superfield approach to the nilpotent symmetry invariance in the non-Abelian 1-form gauge theory

We demonstrate that the nilpotent Becchi-Rouet-Stora-Tyutin (BRST) and anti-BRST symmetry invariance of the Lagrangian density of a four (3 + 1)-dimensional (4D) non-Abelian 1-form gauge theory with Dirac fields can be captured within the framework of the superfield approach to BRST formalism. The above 4D theory, where there is an explicit coupling between the non-Abelian 1-form gauge field and the Dirac fields, is considered on a (4, 2)-dimensional supermanifold, parameterized by the bosonic 4D space-time variables and a pair of Grassmannian variables. We show that the Grassmannian independence of the super Lagrangian density, expressed in terms of the (4, 2)-dimensional superfields, is a clear signature of the presence of the (anti-)BRST invariance in the original 4D theory. PACS numbers: 11.15.-q, 12.20.-m, 03.70.+k