Goldstino superfields for spontaneously broken N=2 supersymmetry

TL;DR

This paper develops a framework for describing Goldstino superfields in spontaneously broken N=2 supersymmetry using harmonic, projective, and conventional superspaces, enabling matter couplings and new formulations of Goldstino actions.

Contribution

It introduces a novel approach to construct Goldstino superfields in N=2 supersymmetry across multiple superspace formalisms, including harmonic and projective superspaces.

Findings

Constructed Goldstino superfields on harmonic superspace.

Reformulated Goldstino action in projective and conventional superspaces.

Derived an N=2 chiral Goldstino action.

Abstract

We examine spontaneously broken N=2 supersymmetry in four dimensions and associate a spinor superfield with each Goldstino via a finite supersymmetry transformation with parameters that are the Grassmann coordinates of N=2 superspace. Making use of a special choice of coset parametrization allows us to develop a version of nonlinearly realized N=2 supersymmetry for which the associated Goldstino superfields are defined on harmonic superspace, thereby providing a natural mechanism for construction of a Goldstino action. The corresponding superfield Lagrangian is an O(4) multiplet. This property is used to reformulate the Goldstino action in projective superspace and in conventional N=2 superspace. We show how to generate matter couplings of the Goldstinos to supersymmetric matter using the N=2 harmonic, projective and full superspaces. As a bi-product of our consideration, we also derive an N=2 chiral Goldstino action.