The Goldstini Variations

TL;DR

This paper explores the phenomenology of multiple goldstini arising from various SUSY-breaking sectors, emphasizing their masses, couplings, and potential collider signatures within string-inspired models.

Contribution

It provides a detailed analysis of goldstini masses and couplings in complex SUSY-breaking scenarios, including warped and sequestered sectors, and discusses their observable implications.

Findings

Goldstini masses can significantly differ from previous predictions due to stabilization effects.

Multiple goldstini and modulini can originate from a single sector with masses around twice the gravitino mass.

Collider signatures involving SSM sparticle decays can reveal properties of hidden SUSY-breaking sectors.

Abstract

We study the 'goldstini' scenario of Cheung, Nomura, and Thaler, in which multiple independent supersymmetry (SUSY) breaking sectors lead to multiple would-be goldstinos, changing collider and cosmological phenomenology. In supergravity, potentially large corrections to the previous prediction of twice the gravitino mass for goldstini masses can arise when their scalar partners are stabilized far from the origin. Considerations arising from the complexity of realistic string compactifications indicate that many of the independent SUSY-breaking sectors should be conformally sequestered or situated in warped Randall-Sundrum-like throats, further changing the predicted goldstini masses. If the sequestered hidden sector is a metastable SUSY-breaking sector of the Intriligator-Seiberg-Shih (ISS) type then multiple goldstini can originate from within a single sector, along with many supplementary 'modulini', all with masses of order twice the gravitino mass. These fields can couple to the Supersymmetric Standard Model (SSM) via the 'Goldstino Portal'. Collider signatures involving SSM sparticle decays can provide strong evidence for warped-or-conformally-sequestered sectors, and of the ISS mechanism of SUSY breaking. Along with axions and photini, the Goldstino Portal gives another potential window to the hidden sectors of string theory.