Low Energy Processes Associated with Spontaneously Broken N=2 Supersymmetry

TL;DR

This paper analyzes low energy processes in N=2 supersymmetry with spontaneous breaking, showing amplitude suppressions involving the Nambu-Goldstone fermion due to specific interactions and cancellations.

Contribution

It provides a detailed formulation of the supercurrent in a model with FI terms and demonstrates how low energy amplitudes are suppressed through cancellations.

Findings

Amplitude suppression at low NGF momentum

Interaction of NGF with U(1) and SU(N) sectors

Cancellation between Yukawa and four-Fermi contact terms

Abstract

We consider low energy processes described by the N=2 supercurrent on its partially (to N=1) and spontaneously broken vacuum and the attendant Nambu-Goldstone fermion (NGF), which the presence of the electric and magnetic Fayet-Iliopoulos (FI) terms is responsible for. We show suppressions of amplitudes decaying into the NGF as its momentum becomes small. In the lagrangian realization (namely, the model of arXiv:hep-th/0409060) of the conserved supercurrent, the NGF resides in the overall U(1), which is nonetheless not decoupled, and interacts with the SU(N) sector through nonderivative as well as derivative couplings. The low energy suppression is instead accomplished by a cancellation between the annihilation diagram from the Yukawa couplings and the contact four-Fermi terms. We give a complete form of the supercurrent and the model is recast in more transparent notation.