Measurement of color flow in t-tbar events from p-pbar collisions at sqrt(s)=1.96 TeV

TL;DR

This paper introduces a novel calorimeter-based variable called 'jet pull' to measure the color flow in top-antitop events, providing the first such measurement consistent with the standard model.

Contribution

The study presents the first measurement of the color representation of W bosons in top-antitop events using the new 'jet pull' variable, based on 5.3 fb^-1 of data from the D0 experiment.

Findings

Measured the fraction of uncolored W bosons as 0.56 ± 0.42

Demonstrated the effectiveness of 'jet pull' in probing color flow

Results are consistent with standard model predictions

Abstract

We present the first measurement of the color representation of the hadronically decaying W boson in t-tbar events, from 5.3 fb^-1 of integrated luminosity collected with the D0 experiment. A novel calorimeter-based vectorial variable, "jet pull," is used, sensitive to the color-flow structure of the final state. We find that the fraction of uncolored W bosons is 0.56 +- 0.42(stat+syst), in agreement with the standard model.