The Top Quark Production Asymmetries $A_{FB}^t$ and $A_{FB}^{\ell}$

TL;DR

This paper investigates the relationship between top quark and charged lepton asymmetries at the Tevatron, highlighting how spin correlations influence these measurements and suggesting new physics models favoring right-handed top quarks.

Contribution

It analyzes the connection between $A_{FB}^t$ and $A_{FB}^ ext{l}$ through spin correlations, proposing that models with right-handed top quarks better explain the data.

Findings

Both asymmetries are linked via spin correlations.

Data favors models with more right-handed top quarks.

The study emphasizes the importance of measuring both asymmetries.

Abstract

A large forward-backward asymmetry is seen in both the top quark rapidity distribution $A_{FB}^t$ and in the rapidity distribution of charged leptons $A_{FB}^\ell$ from top quarks produced at the Tevatron. We study the kinematic and dynamic aspects of the relationship of the two observables arising from the spin correlation between the charged lepton and the top quark with different polarization states. We emphasize the value of both measurements, and we conclude that a new physics model which produces more right-handed than left-handed top quarks is favored by the present data.