Vector-like quarks and heavy coloured bosons at the LHC

TL;DR

This paper explores how heavy coloured scalars and vectors at the LHC can be used to detect and set limits on vector-like quarks, especially in models with heavy bosonic states decaying into VLQ and top quarks.

Contribution

It introduces a universal analysis strategy for detecting VLQ signals via heavy coloured bosons, applicable across various models and capable of probing masses up to 3 TeV.

Findings

Heavy coloured bosons can significantly enhance VLQ detection prospects.

A simple set of cuts can effectively distinguish VLQ signals from backgrounds.

The method can set strong limits on VLQ masses up to 3 TeV.

Abstract

We investigate the production of heavy coloured scalars and vectors and their relevance at LHC for the study of vector-like quarks ($T$). These coloured states ($C$) are present in a large number of extensions of the standard model, in particular in composite models and in extra dimensional models. Assuming that these bosonic states are heavier than the vector-like quarks (VLQ), we consider their production through the process $p~p\rightarrow C\rightarrow tT$. Large QCD production cross-sections for $C$ enable us to probe heavier masses for the VLQ and thereby allowing to put stronger limits on the vector-like quarks which are produced in their decay chain. We adopt a universal analysis strategy by including leptons under the classification of `jets', thereby limiting the bias towards a specific combination of final state. We also study the possibility of disentangling these scenarios from supersymmetric extensions of the Standard Model by using simple discriminants based on jet multiplicity and missing energy. We demonstrate that a simple set of cuts are sufficient to disentangle the VLQ signal from the backgrounds. In models with a moderate $B.R.(C\rightarrow Tt)$, the analysis enables one to get a hint of VLQ masses as heavy as 3 TeV.