On N=2 supergravity and projective superspace: Dual formulations

The superspace formulation for four-dimensional N = 2 matter-coupled supergravity recently developed in [S.M. Kuzenko, U. Lindstrom. M. Rocek, G. Tartaglino-Mazzucchelli, 4D N = 2 supergravity and projective superspace. arXiv: 0805.4683] makes use of a new type of conformal compensator with infinitely many off-shell degrees of freedom: the so-called covariant weight-one polar hypermultiplet. In the present note we prove file duality of this formulation to the known minimal (40 + 40) off-shell realization for N = 2 Poincare supergravity involving the improved tensor compensator Within the latter formulation, we present new off-shell matter Couplings realized in terms of covariant weight-zero polar hypermultiplets. We also elaborate upon the projective superspace description of Vector multiplets in N = 2 conformal supergravity. An alternative superspace representation for locally supersymmetric chiral actions is given. We present a model for massive improved tensor multiplet with both electric and magnetic types of mass terms. (c) 2008 Elsevier B.V. All rights reserved.