Collider signatures of vector-like fermions from a flavor symmetric model

TL;DR

This paper introduces a flavor symmetric model with vector-like fermions, analyzing their collider signatures and potential for discovery at the LHC, including implications for the muon magnetic moment anomaly.

Contribution

It presents a novel flavor symmetric model with vector-like fermions, detailing collider signatures and discovery prospects at the LHC, extending beyond the Standard Model.

Findings

VLLs can be probed up to 200 GeV mass at LHC

VLQs can be detected up to 3.8 TeV at high luminosity

Model explains muon anomalous magnetic moment

Abstract

We propose a model with two Higgs doublets and several $SU(2)$ scalar singlets with a global non-Abelian flavor symmetry $\mathcal{Q}_6\times\mathcal{Z}_2$. This discrete group accounts for the observed pattern of fermion masses and mixing angles after spontaneous symmetry breaking. In this scenario only the third generation of fermions get their masses as in the Standard Model (SM). The masses of the remaining fermions are generated through a seesaw-like mechanism. To that end, the matter content of the model is enlarged by introducing electrically charged vector-like fermions (VLFs), right handed Majorana neutrinos and several SM scalar singlets. Here we study the processes involving VLFs that are within the reach of the Large Hadron Collider (LHC). We perform collider studies for vector-like leptons (VLLs) and vector-like quarks (VLQs), focusing on double production channels for both cases, while for VLLs single production topologies are also included. Utilizing genetic algorithms for neural network optimization, we determine the statistical significance for a hypothetical discovery at future LHC runs. In particular, we show that we can not safely exclude VLLs for masses greater than $200~\mathrm{GeV}$. For VLQ's in our model, we show that we can probe their masses up to 3.8 TeV, if we take only into account the high-luminosity phase of the LHC. Considering Run-III luminosities, we can also exclude VLQs for masses up to $3.4~\mathrm{TeV}$. We also show how the model with predicted VLL masses accommodates the muon anomalous magnetic moment.