A Chern-Weil Isomorphism for the Equivariant Brauer Group
  In this paper we construct a Chern-Weil isomorphism for the equivariant Brauer group of R^n-actions on a principal torus bundle, where the target for this isomorphism is a "dimensionally reduced" Cech cohomology group. From this point of view, the usual forgetful functor takes the form of a connecting homomorphism in a long exact sequence in dimensionally reduced cohomology. 
Peter Bouwknegt, Alan Carey and Rishni Ratnam
math.OA math-ph math.MP