A survey of top quark polarization at a polarized linear e^+ e^- collider

TL;DR

This paper reviews how to control and optimize top quark polarization in electron-positron collisions at linear colliders, including detailed calculations and the effects of beam polarization on spin correlations.

Contribution

It provides a comprehensive survey of top quark polarization phenomena at polarized linear e^+ e^- colliders, including next-to-leading order QCD calculations and polarization tuning strategies.

Findings

Maximization and minimization of top quark polarization achieved by beam polarization tuning

Detailed NLO QCD calculations of top quark polarization

Analysis of beam polarization effects on top-antitop spin correlations

Abstract

We discuss in detail top quark polarization in above-threshold (t \bar t)-production at a polarized linear e^+ e^- collider. We pay particular attention to the minimization and maximization of the polarization of the top quark by tuning the longitudinal polarization of the e^+ and e^- beams. The polarization of the top quark is calculated in full next-to-leading order QCD. We also discuss the beam polarization dependence of the longitudinal spin-spin correlations of the top and antitop quark spins.