Supersymmetry Breaking by Type II Seesaw Assisted Anomaly Mediation

TL;DR

This paper demonstrates that incorporating a type II seesaw mechanism into anomaly mediated supersymmetry breaking can resolve the negative slepton mass problem, leading to positive slepton masses and a viable supersymmetric model.

Contribution

It introduces a model where the type II seesaw mechanism deflects anomaly mediation, ensuring positive slepton masses while maintaining gauge coupling unification.

Findings

Slepton masses become positive with the seesaw extension.

Bino is the LSP with nearly degenerate NLSP slepton.

Seesaw scale is around 10^{13}-10^{14} GeV.

Abstract

Anomaly mediated supersymmetry breaking (AMSB), when implemented in MSSM is known to suffer from the problem of negative slepton mass squared leading to breakdown of electric charge conservation. We show however that when MSSM is extended to explain small neutrino masses by including a pair of superheavy Higgs triplet superfields (the type II seesaw mechanism), the slepton masses can be deflected from the pure AMSB trajectory and become positive. In a simple model we present in this paper, the seesaw scale is about $10^{13}-10^{14}{\rm GeV}$. Gauge coupling unification can be maintained by embedding the triplet to SU(5) {\bf 15}-multiplet. In this scenario, bino is the LSP and its mass is nearly degenerate with NLSP slepton when the triplet mass is right around the seesaw scale.