Dependence of the top-quark mass measured in top-quark pair production on the parton distribution functions at the LHC and future colliders

TL;DR

This paper investigates how the measurement of the top-quark mass in top-antitop production depends on parton distribution functions at various collider energies, proposing methods to reduce associated uncertainties.

Contribution

It introduces a method to reduce the top-quark mass uncertainty from PDF uncertainties by fitting the longitudinal momentum of the top-antitop system across different collider energies.

Findings

Parton distribution function uncertainties can be reduced by 20%.

The study covers collider energies from 8 TeV to 100 TeV.

A chi-squared fit to the invariant mass is used for mass extraction.

Abstract

The dependence of the top-quark mass measurement in top-quark production on the parton distribution functions is explored through the differential distribution of the invariant mass of the top-antitop system in top-quark pair production at hadron colliders. Several different proton-proton collider options are considered: 8 TeV, 13 TeV, 13.6 TeV, 14 TeV, and 100 TeV. The top-quark mass is obtained from a chi-squared fit to the invariant mass of the top-antitop-quark pair. The parton distribution function uncertainties are used in the chi-square evaluation. The uncertainties are reduced through a fit to the longitudinal momentum of the top-antitop system. The top-quark mass uncertainty due to parton distribution functions is found to be reduced by 20%.