Supersymmetric type-III seesaw: lepton flavour violation and LHC phenomenology

TL;DR

This paper explores supersymmetric type-III seesaw models, analyzing their implications for lepton flavor violation and potential detection at the LHC, with a focus on different model variants and their experimental constraints.

Contribution

It introduces and compares minimal and extended supersymmetric type-III seesaw models, analyzing their phenomenology and compatibility with experimental bounds, and assesses their testability at the LHC.

Findings

Two-24-plet model can evade lepton flavor violation bounds under certain conditions.

Lepton flavor violation constraints are easier to satisfy with two 24-plets.

LHC can potentially test flavor structures in favorable scenarios.

Abstract

We study a supersymmetric version of the seesaw mechanism type-III considering two variants of the model: a minimal version for explaining neutrino data with only two copies of 24-plet superfields and a model with three generations of 24-plets. The latter predicts in general rates for $\mu\to e\gamma$ inconsistent with experimental data. However, this bound can be evaded if certain special conditions within the neutrino sector are fulfilled. In case of two 24-plets lepton flavour violation constraints can be satisfied much easier. After specifying the corresponding regions in the CMSSM parameter space we show that under favorable conditions one can test the corresponding flavour structures in the leptonic sector at the LHC. For this we perform Monte Carlo studies for the signals taking also into account the SUSY background. We find that it is only of minor importance for the scenarios studied here.