New Strongly Coupled Sector at the Tevatron and the LHC

TL;DR

This paper explores a new strongly coupled sector involving a color-octet interaction and a fourth-generation of quarks, which could explain anomalies in top quark production and be observable at the Tevatron and LHC.

Contribution

It introduces a novel effective theory framework for a strongly coupled sector with a fourth-generation, analyzing its phenomenology and experimental signatures at colliders.

Findings

Potential explanation for top forward-backward asymmetry

Predicted observable signals of fourth-generation quarks at Tevatron

LHC should detect fourth-generation quarks with higher-than-QCD predicted rates

Abstract

We examine the possibility that a new strong interaction is accessible to the Tevatron and the LHC. In an effective theory approach, we consider a scenario with a new color-octet interaction with strong couplings to the top quark, as well as the presence of a strongly coupled fourth-generation which could be responsible for electroweak symmetry breaking. We apply several constraints, including the ones from flavor physics. We study the phenomenology of the resulting parameter space at the Tevatron, focusing on the the forward-backward asymmetry in top pair production, as well as in the production of the fourth-generation quarks. We show that if the excess in the top production asymmetry is indeed the result of this new interaction, the Tevatron could see the first hints of the strongly coupled fourth-generation quarks. Finally, we show that the LHC with $\sqrt{s}=7~$TeV and $1~{\rm fb}^{-1}$ integrated luminosity should observe the production of fourth-generation quarks at a level at least one order of magnitude above the QCD prediction for the production of these states.