Supersymmetric extension of the nine-dimensional continuation of the Euler density with N=2

TL;DR

This paper constructs a local N=2 supersymmetric extension of the nine-dimensional Euler density, incorporating super Poincare symmetry and formulating the Lagrangian as a Chern-Simons action.

Contribution

It introduces the first explicit local supersymmetric extension of the nine-dimensional Euler density with N=2, including a detailed supergravity field content and symmetry structure.

Findings

Super Poincare invariance with N=2 established

Full Lagrangian expressed as a Chern-Simons form

Invariance under local Poincare translations confirmed

Abstract

A local supersymmetric extension with N=2 of the dimensional continuation of the Euler-Gauss-Bonnet density from eight to nine dimensions is constructed. The gravitational sector is invariant under local Poincare translations, and the full field content is given by the vielbein, the spin connection, a complex gravitino, and an Abelian one-form. The local symmetry group is shown to be super Poincare with N=2 and a U(1) central extension, and the full supersymmetric Lagrangian can be written as a Chern-Simons form.