Enhancing the sensitivity to New Physics in the top-antitop invariant mass distribution

TL;DR

This paper proposes specific event selection cuts at the LHC to increase the sensitivity to New Physics signals in top-antitop invariant mass distributions by enhancing quark-fusion events and analyzing the impact of systematic errors.

Contribution

It introduces a novel set of selection cuts that improve the detection potential of New Physics in top-antitop events by increasing quark-fusion contributions and analyzing systematic uncertainties.

Findings

Selection cuts increase quark-fusion fraction in top-antitop events.

Enhanced sensitivity to non-visible new particles through resonance bump analysis.

Systematic errors significantly affect the potential discovery sensitivity.

Abstract

We propose selection cuts on the LHC top-antitop production sample which should enhance the sensitivity to New Physics signals in the study of the top-antitop invariant mass distribution. We show that selecting events in which the top-antitop object has little transverse and large longitudinal momentum enlarges the quark-fusion fraction of the sample and therefore increases its sensitivity to New Physics which couples to quarks and not to gluons. We find that systematic error bars play a fundamental role and assume a simple model for them. We check how a non-visible new particle would become visible after the selection cuts enhance its resonance bump. A final realistic analysis should be done by the experimental groups with a correct evaluation of the systematic error bars.