Heavy-quark pair production at lepton colliders at NNNLO in QCD

TL;DR

This paper presents a high-precision calculation of heavy-quark pair production in electron-positron collisions at NNNLO in QCD, reducing theoretical uncertainties to meet future collider standards.

Contribution

It provides the first NNNLO QCD predictions for heavy-quark pair production at lepton colliders, with results expressed as piecewise power series for efficient computation.

Findings

Total cross-section correction of ~0.1% at 500 GeV

Invariant mass distribution correction of ~10%

Scale dependence reduced to 0.06% for cross-section

Abstract

We compute the total cross-section and invariant mass distribution for heavy-quark pair production in $e^+e^-$ annihilation at the next-to-next-to-next-to-leading order in QCD. The obtained results are expressed as piecewise functions defined by several deeply expanded power series, facilitating a rapid numerical evaluation. Utilizing top-pair production at a collision energy of 500 GeV as a benchmark, we observe a correction of approximately $0.1\%$ for the total cross-section and around $10\%$ for the majority of the invariant mass distribution range. These results play a crucial role in significantly reducing theoretical uncertainty: the scale dependence has been diminished to $0.06\%$ for the total cross-section and to $5\%$ for the invariant mass distribution. This reduction of uncertainty meets the stringent requirements of future lepton colliders.