Superfield approach to BRST cohomology

In the framework of superfield formalism, we discuss some aspects of cohomological features of a two(1+1)-dimensional free Abelian gauge theory that is described by a BRST invariant Lagrangian density in the Feynman gauge. We demonstrate that the conserved and nilpotent (anti-)BRST- and (anti-)co-BRST charges are the generators of translations along the Grassmannian directions of the four-dimensional supermanifold. A conserved bosonic charge is shown to generate a translation along the spacetime direction of the supermanifold. These charges turn out to be analogous to the de Rham cohomology operators of differential geometry defined on the supermanifold and they generate local symmetry transformations for the Lagrangian density of the theory.