Top-antitop resonance searches beyond 1 TeV

TL;DR

This paper analyzes how to improve the detection of heavy resonant states in top-antitop pair production at the LHC, focusing on kinematic variables to distinguish quark-annihilation processes for masses above 1 TeV.

Contribution

It introduces optimized kinematic cuts, especially on the scattering angle, to enhance the sensitivity of heavy resonance searches beyond 1 TeV at the LHC.

Findings

$ heta$ is a better discriminant than $eta$ for invariant masses above 1 TeV.

Applying cuts on $ heta$ improves the signal sensitivity for a 1.5 TeV gluon resonance.

The analysis demonstrates increased detection potential with the proposed kinematic selections.

Abstract

We perform a general parton level analysis for the search of heavy resonant states in the production of top-antitop pairs at the LHC with an integrated luminosity of 30 fb^-1. We assume the existence of resonances that only couple to quarks and propose kinematic cuts in order to increase the amount of events produced through quark-annihilation. We study the interplay between different variables and their impact on the purity of the selected sample. We make focus on the longitudinal ($\beta$) and transverse ($p_T$) momentum of the top-antitop pair, and the scattering angle ($\theta$) in the center of mass reference frame. We observe that $\beta$ is replaced by $\theta$ as a suitable discriminating variable of quark-annihilation processes for invariant masses above 1 TeV. Finally, we illustrate the analysis with a gluon resonance of 1.5 TeV and show the improvement in the sensitivity of the signal when cuts on $\theta$ are imposed.