LHC signatures of neutrino mass generation through R-parity violation

TL;DR

This paper explores how neutrino mass models with R-parity violation could produce detectable signals at the LHC, focusing on stop squark decays that yield leptons and jets, constrained by recent neutrino data.

Contribution

It provides a detailed analysis of LHC signatures of RPV supersymmetry models consistent with neutrino oscillation data, highlighting potential observable signals involving stop decays.

Findings

Stop decays produce leptons and jets detectable at LHC

Neutrino data constrains RPV coupling strengths

Signals are observable for a range of stop masses

Abstract

We consider a model of neutrino mass based on R-parity violating (RPV) supersymmetry, with three $\mu_i$, relevant for bilinear RPV terms, and three $\lambda'_{ijk}$, relevant for the trilinear terms. The present neutrino data, after a precise determination of the mixing angle $\theta_{13}$, severely constrain such models. We make a thorough study of one such class of models that may have interesting signatures at the upgraded LHC. In this class of models, the relevant trilinear couplings are of the form $\lambda'_{i33}$, so if the lighter stop squark $\tilde{t}_1$ is the lightest supersymmetric particle (LSP), it will decay only through these couplings, giving rise to events with isolated hard leptons and jets. Even when $\tilde{t}_1$ is the next-to-LSP (NLSP), it can decay via the tiny $\lambda'$ couplings allowed by the neutrino data, although it may face stiff competition from some R-parity conserving decay modes. Using a simple Pythia based simulation, we find that in both the cases the signal consisting of a pair of oppositely charged leptons ($ee$, $\mu \mu$ or $e \mu $) plus jets may be observable at the upgraded LHC experiments for a reasonable range of the $\tilde{t}_1$ mass.