Nilpotent Symmetries for Matter Fields in Non-Abelian Gauge Theory: Superfield Formalism

The derivation of the (anti-)BRST nilpotent symmetries for the matter fields in any arbitrary interacting gauge theory has been a long-standing problem in the framework of superfield approach to BRST formalism. In the present paper, the local, covariant, continuous and off-shell nilpotent (anti-)BRST symmetries for the Dirac fields (ψ, ψ̄) are derived in the framework of superfield formulation where the four (3+1)-dimensional (4D) interacting non-Abelian gauge theory is considered on the six (4+2)-dimensional supermanifold parametrized by the four even spacetime coordinates x and a couple of odd elements (θ and θ̄) of the Grassmann algebra. The invariance of the matter (super)currents and the horizontality condition on the (super)manifolds lead to the derivation of the nilpotent symmetries for the matter fields as well as the gauge and (anti-)ghost fields of the theory. PACS: 11.15.-q; 12.20.-m; 03.70.+k