An extended BRST-anti-BRST invariant description of Maxwell-Chern-Simons gauge theory coupled to scalar field in superspace

Abstract {We discuss the extended BRST and anti-BRST transformations for Maxwell-Chern-Simons gauge theory coupled to scalar field in the framework of Batalin-Vilkovisky description. Besides we demonstrate that the extended BRST and BRST-anti-BRST invariant Lagrangian density of the MCS theory can be formulated in terms of superfields with one or two fermionic coordinates respectively in the superspace. Moreover, we propose a new type of extended BRST-anti-BRST transformation and show that the resulting effective action in this construction coincides with the standard form.