Higher dimensional Chern-Simons supergravity.

A Chern-Simons action for supergravity in odddimensional spacetimes is proposed. For all odd dimensions, the local symmetry group is a non trivial supersymmetric extension of the Poincaré group. In 2 + 1 dimensions the gauge group reduces to super-Poincaré, while for D = 5 it is superPoincaré with a central charge. In general, the extension is obtained by the addition of a 1-form field which transforms as an antisymmetric fifth-rank tensor under Lorentz rotations. Since the Lagrangian is a Chern-Simons density for the supergroup, the supersymmetry algebra closes off shell without the need of auxiliary fields. PACS numbers: 04.50.+h, 04.65.+e, 11.10.K