Search for anomalous top-gluon couplings at LHC revisited

TL;DR

This paper investigates how nonstandard top-gluon couplings could affect top-quark pair production at the LHC, providing a way to detect potential new physics beyond the Standard Model through deviations in cross sections and distributions.

Contribution

It calculates the impact of dimension-6 effective operators on top-quark pair production at LHC, focusing on chromoelectric and chromomagnetic moments, and assesses their observable effects.

Findings

LHC could observe sizable effects from anomalous top-gluon couplings.

Constraints from Tevatron measurements limit the parameter space.

Potential to detect new physics effects in top-quark production distributions.

Abstract

Through top-quark pair productions at LHC, we study possible effects of nonstandard top-gluon couplings yielded by SU(3)xSU(2)xU(1) invariant dimension-6 effective operators. We calculate the total cross section and also some distributions for p p -> t tbar X as functions of two anomalous-coupling parameters, i.e., the chromoelectric and chromomagnetic moments of the top, which are constrained by the total cross section sigma(p pbar -> t tbar X) measured at Tevatron. We find that LHC might give us some chances to observe sizable effects induced by those new couplings.