On N = 2 supergravity and projective superspace: Dual formulations

TL;DR

This paper demonstrates the duality between two formulations of N=2 supergravity in superspace, introduces new matter couplings, and explores projective superspace descriptions of vector multiplets and chiral actions.

Contribution

It proves the duality between a covariant polar hypermultiplet formulation and the minimal off-shell realization, and presents new matter couplings and superspace representations.

Findings

Established duality between two supergravity formulations.

Introduced new off-shell matter couplings with covariant polar hypermultiplets.

Provided a model for massive improved tensor multiplet with electric and magnetic mass terms.

Abstract

The superspace formulation for four-dimensional N = 2 matter-coupled supergravity recently developed in 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 the 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.