Looking beyond the Standard Model with Third Generation Quarks at the LHC

Trisha Farooque,Hector de la Torre

doi:10.3390/sym14030444

Abstract

The Large Hadron Collider (LHC) is at the frontier of collider physics today, probing new physics at unprecedented energy scales. Many theories of physics beyond the Standard Model seek to elucidate the underlying mechanism of electroweak symmetry breaking. Given their large Yukawa couplings to the Higgs boson, third generations quarks of the Standard Model, and especially the top quark, play a key role in such theories. Therefore, new particles predicted by these theories often couple preferentially to top and bottom quarks. The favoured coupling to third generation can also be used to explain recently observed flavour physics anomalies in the LHCb, Babar or Belle experiments. This article will review recent searches for new physics performed by the ATLAS and CMS experiments at the LHC, in final states containing top and bottom quarks. In particular, searches for vector-like quarks, leptoquarks, and heavy scalar and gauge bosons will be discussed.

Highlights

The study of third generation quarks is one of the main focuses of research at the Large Hadron Collider (LHC) [1]
Searches with third generation quarks in the final state are a crucial element of any programme that looks for these exotics particles and are the topic of a wide array of searches performed by both the ATLAS [11] and CMS [12] Collaborations
It is divided into three different sections: Vector-LikeQuark (VLQ) searches, Leptoquark (LQ) searches, and other resonant searches that are not aiming to specific models but rather look for resonant behaviour in final states with at least one top-quark

Summary

Introduction

The study of third generation quarks is one of the main focuses of research at the LHC [1]. Their high mass, especially in the case of the top-quark, makes them of particular interest the mechanism of electroweak symmetry breaking and the Higgs-boson properties. This review presents a collection of those searches, all of them using pp collision data at a centre-of-mass energy of 13 TeV. It is divided into three different sections: Vector-LikeQuark (VLQ) searches, Leptoquark (LQ) searches, and other resonant searches that are not aiming to specific models but rather look for resonant behaviour in final states with at least one top-quark.

The Phenomenology of Vector-like Quarks

The Phenomenology of Leptoquarks

Other Relevant Phenomenology

Vector-like Quark Searches

Searches for the Pair Production of VLQs

Searches for the Single Production of VLQs

10-2 Both forward jets categories

Searches for Exotic Production of VLQs

Leptoquark Searches