Linear power corrections to top quark pair production in hadron collisions

TL;DR

This paper calculates the leading non-perturbative power corrections to top quark pair production cross sections and distributions in hadron collisions, highlighting their dependence on kinematics and the importance of mass scheme choices.

Contribution

It provides the first calculation of ${ m O}(\Lambda_{ m QCD})$ corrections to top pair production using renormalon calculus, emphasizing the impact of mass scheme on corrections.

Findings

Linear power correction to total cross section vanishes with a short-distance mass scheme.

Power corrections depend on top quark kinematics.

Corrections are numerically small but kinematically interesting.

Abstract

We compute, in the framework of renormalon calculus, the ${\cal O}(\Lambda_{\rm QCD})$ corrections to the production of $t\bar{t}$ pairs in hadron collisions under the assumption that $q \bar q \to t \bar t$ is the dominant partonic channel. This assumption is not applicable to top quark pair production at the LHC but it is valid for the Tevatron where collisions of protons and anti-protons were studied. We show that the linear power correction to the total $t \bar t$ production cross section vanishes provided one uses a short-distance scheme for the top quark mass. We also derive relatively simple formulas for the power corrections to top quark kinematic distributions. Although small numerically, these power corrections exhibit interesting dependencies on top quark kinematics.