Exploring the impact of high-precision top-quark pair production data on the structure of the proton at the LHC

TL;DR

This paper investigates how recent high-precision top-quark pair production data from the LHC influence the understanding of the proton's internal structure, especially the gluon distribution, within a global analysis framework.

Contribution

It extends the CT18 global analysis to incorporate new 13 TeV top-quark data and examines their effects on parton distribution functions and theoretical modeling.

Findings

High-precision top-quark data significantly constrain the gluon PDF.

The data impact the PDFs at intermediate and large x values.

Scale choice affects the theoretical description of top-quark pair production.

Abstract

The impact of recent LHC top-quark pair production single differential cross section measurements at 13 TeV collision energy on the structure of the proton is explored. In particular, the impact of these high-precision data on the gluon and other parton distribution functions (PDFs) of the proton at intermediate and large partonic momentum fraction $x$ is analyzed. This study extends the CT18 global analysis framework to include these new data. The interplay between top-quark pair and inclusive jet production as well as other processes at the LHC, is studied. In addition, a study of the impact of scale choice on the theory description of the new 13 TeV $t\bar t$ measurements is performed.