Scale dependence of top-quark cross section at $e^+e^-$ colliders near production threshold at NNNLO

TL;DR

This paper analyzes the scale dependence of the top-quark pair production cross section near threshold at $e^+e^-$ colliders, demonstrating that precise measurements could determine the top-quark mass with about 30 MeV accuracy.

Contribution

It provides a detailed study of the scale dependence at NNNLO and assesses the theoretical accuracy of top-quark mass extraction from threshold scans.

Findings

Threshold scan can determine top-quark mass with ~30 MeV accuracy

NNNLO prediction reduces theoretical uncertainties

Scale dependence analysis improves understanding of top-quark production near threshold

Abstract

The top-quark threshold cross section at $e^+e^-$ colliders near production threshold is investigated. We study the scale dependence of the cross section for $\sigma(e^+e^- \to ttX$) near $\sqrt{s} \simeq 2m_t$ and discuss the theoretical accuracy of the NNNLO prediction. We report that a threshold scan at an $e^+e^-$ collider would allow a determination of the top-quark mass with an accuracy of order 30 MeV.