Search for anomalous top quark production at the early LHC

TL;DR

This paper investigates the potential for early LHC data to detect anomalous top quark production caused by flavor-changing neutral currents, including next-to-leading order QCD effects and methods to distinguish different couplings.

Contribution

It provides a model-independent analysis of anomalous top production at the LHC, incorporating NLO QCD effects and exploring discovery potential with low luminosity.

Findings

LHC at 7 TeV could discover anomalous couplings with only 61 pb$^{-1}$ of data.

The study estimates the discovery reach for flavor-changing neutral currents involving top quarks.

Charge ratio analysis can help differentiate between $tug$ and $tcg$ couplings.

Abstract

We present a detailed study of the anomalous top quark production with subsequent decay at the LHC induced by model-independent flavor-changing neutral-current couplings, incorporating the complete next-to-leading order QCD effects. Our results show that, taking into account the current limits from the Tevatron, the LHC with $\sqrt{s}=7$ TeV may discover the anomalous coupling at 5$\sigma$ level for a very low integrated luminosity of 61 pb$^{-1}$. The discovery potentials for the anomalous couplings at the LHC are examined in detail. We also discuss the possibility of using the charge ratio to distinguish the $tug$ and $tcg$ couplings.