Effective field theory for top physics

TL;DR

This paper investigates the top forward-backward asymmetry using an effective field theory approach, analyzing how dimension-6 operators influence top quark production and related observables to probe potential new physics.

Contribution

It introduces an effective Lagrangian framework to study top asymmetry and related observables, providing new insights into chiral structures and potential beyond Standard Model physics.

Findings

Dimension-6 operators affect top pair production and asymmetry.

FB spin-spin correlation is strongly linked to A_FB.

Longitudinal top polarization offers a new probe for chiral new physics.

Abstract

We study the top forward-backward asymmetry (FBA $\equiv A_{\rm FB}$) reported by CDF and D0 Collaborations in the effective lagrangian approach. Using dimension-6 effective largrangians for $q \bar{q} \rightarrow t \bar{t}$, we study the $t\bar{t}$ production cross section and the $A_{\rm FB}$, and a few observables: the FB spin-spin correlation that is strongly correlated with the $A_{\rm FB}$, and longitudinal top polarization as a new probe of chiral structures for possible new physics scenarios.