Implications of the effective axial-vector coupling of gluon on top-quark charge asymmetry at the LHC

TL;DR

This paper investigates how an effective axial-vector gluon coupling affects top-quark charge asymmetries and cross sections at the LHC, highlighting the importance of rapidity cuts and invariant mass dependence for detecting new physics.

Contribution

It introduces the impact of an effective axial-vector gluon coupling on top-quark asymmetries and cross sections, emphasizing the sensitivity of rapidity-dependent asymmetries to new physics.

Findings

Rapidity cut-dependent asymmetries are more sensitive to new physics.

LHC at 7 TeV can confirm or rule out the Tevatron top asymmetry anomaly.

Measurements of asymmetries and cross sections as functions of invariant mass are crucial.

Abstract

We study different top quark charge asymmetries and the variation of $t\bar t$ total cross section induced by the effective axial-vector coupling of gluon in the LHC experiments. We show that rapidity cut-dependent asymmetries are more sensitive to the new physics than the independent ones. We also study the dependence of the asymmetries and variations of total $t\bar t$ cross sections on the invariant mass of $t\bar t$ system and show that it would be necessary to measure those quantities as functions of $m_{tt}$ at the LHC. In the context of considered new physics scenario, 7 TeV LHC has enough sensitivity either to confirm the Tevatron top asymmetry anomaly or to rule it out. In the latter case the LHC is able to put stringent constraint on the new physics scale $\Lambda$ in this framework.