Superfield approach to nilpotent (anti-)BRST symmetries for the free Abelian 2-form gauge theory

We derive the off-shell nilpotent Becchi-Rouet-Stora-Tyutin (BRST) and antiBRST symmetry transformations for all the fields of a free Abelian 2-form gauge theory by exploiting the geometrical superfield approach to BRST formalism. The above four (3 + 1)dimensional (4D) theory is considered on a (4, 2)-dimensional supermanifold parameterized by the four even spacetime variables x (with μ = 0, 1, 2, 3) and a pair of odd Grassmannian variables θ and θ̄ (with θ = θ̄ = 0, θθ̄ + θ̄θ = 0). The horizontality condition, owing its origin to the super exterior derivative on the above supermanifold, plays a key role in the above derivation. The geometrical interpretations for the above (anti-)BRST symmetry transformations (and their corresponding generators) are provided within the framework of the superfield approach to BRST formalism. The on-shell nilpotent versions of the above off-shell nilpotent (anti-)BRST symmetry transformations are also derived by invoking the (anti-)chiral superfields. Some novel features associated with the free Abelian 2-form gauge theory are pointed out vis-à-vis the (non-)Abelian 1-form gauge theories when both the above types of theories are discussed within the framework of the superfield formalism. PACS numbers: 11.15.-q, 12.20.-m, 03.70.+k