Forward-Backward Asymmetry in Top Quark Production in ppbar Collisions at sqrt{s}=1.96 TeV

TL;DR

This paper measures the forward-backward asymmetry in top quark production in proton-antiproton collisions at 1.96 TeV, testing discrete symmetries and providing parton-level asymmetry values based on experimental data.

Contribution

It introduces a method to measure and correct for experimental distortions of top quark asymmetries in ppbar collisions, deriving values at the parton level.

Findings

Measured asymmetry in ppbar frame: 0.17 ± 0.08

Measured asymmetry in ttbar frame: 0.24 ± 0.14

Provides corrected parton-level asymmetry values

Abstract

Reconstructable final state kinematics and charge assignment in the reaction ppbar->ttbar allows tests of discrete strong interaction symmetries at high energy. We define frame dependent forward-backward asymmetries for the outgoing top quark in both the ppbar and ttbar rest frames, correct for experimental distortions, and derive values at the parton-level. Using 1.9/fb of ppbar collisions at sqrt{s}=1.96 TeV recorded with the CDF II detector at the Fermilab Tevatron, we measure forward-backward top quark production asymmetries in the ppbar and ttbar rest frames of A_{FB,pp} = 0.17 +- 0.08 and A_{FB,tt} = 0.24 +- 0.14.