Towards the fate of natural composite Higgs model through single $t^\prime$ search at the 8 TeV LHC

TL;DR

This paper investigates the potential to detect a heavy top partner ($t'$) at the 8 TeV LHC through single production channels, using jet substructure techniques to improve Higgs reconstruction, and sets constraints on the $t'$ coupling.

Contribution

It introduces a novel analysis of single $t'$ production at 8 TeV LHC within a minimal composite Higgs model, emphasizing boosted decay products and jet substructure methods.

Findings

Strong constraints on $t'$ coupling at 95% CL for masses 700-1000 GeV.

Single $t'$ production is less suppressed and more promising for heavy $t'$ searches.

Jet substructure techniques improve Higgs reconstruction in $th$ decay channel.

Abstract

We analyze the observational potential of single $t'$ production in both the $t^\prime \rightarrow bW$ and $t^\prime \rightarrow th$ decay channels at 8 TeV LHC using an integrated luminosity of 25 $\text{fb}^{-1}$. Our analysis is based on a simplified model with minimal coset $SO(5)/SO(4)$ in which the $t'$ is a singlet of the unbroken SO(4). The single $t'$ production, as a consequence of electroweak symmetry breaking, is less kinematically suppressed, associated with a light forward jet and has boosted decay products at the 8 TeV LHC. Therefore it provides the most promising channel in searching for a heavy $t'$. We have exploited the above kinematical features and used the jet substructure method to reconstruct the boosted Higgs in $th$ decay channel. It is shown that a strong constraint on the $t^\prime bW$ coupling ($g_{t^\prime bW}/g_{tbW,SM} < 0.2 \sim 0.3$) at the 95% C. L. can be obtained for $m_{t'} \subset (700, 1000)$ GeV.