Electroweak effects in top-quark pair production at Hadron Colliders

TL;DR

This paper computes the full electroweak one-loop corrections to top-quark pair production via gluon fusion at hadron colliders, including previously omitted contributions and keeping bottom-quark mass effects. Using on-shell renormalization and Passarino–Veltman reduction, it delivers compact analytic expressions for the virtual corrections, categorized into vertex, self-energy, box, and triangle diagrams, with explicit treatment of Higgs and Z+Goldstone triangles and thorough cross-checks against prior results. Numerically, the EW corrections are modest for inclusive cross sections but can significantly modify differential distributions at high energies, reaching 10–15% corrections in large-$p_T$ or large-$M_{t\bar t}$ regions at the LHC, and exhibit notable Higgs-mass dependence near threshold. The work resolves discrepancies with some earlier studies and provides a robust analytic framework for precision top-quark phenomenology and potential explorations of new physics in differential observables. It also lays groundwork for extending EW corrections to related processes such as bottom-quark production.

Abstract

Top-quark physics plays an important role at hadron colliders such as the Tevatron collider at Fermilab or the upcoming Large Hadron Collider (LHC) at CERN. Given the planned experimental precision, detailed theoretical predictions are mandatory. In this article we present analytic results for the complete electroweak corrections to gluon induced top-quark pair production, completing our earlier results for the quark-induced reaction. As an application we discuss top-quark pair production at Tevatron and at LHC. In particular we show that, although small for inclusive quantities, weak corrections can be sizeable for differential distribution.

Figures (15)

• Figure 1 : Pictorial representation of contributions missing in Ref. Beenakker:1993yr
• Figure 1 : Born diagrams for top-quark pair production via gluon fusion.
• Figure 1 : Different contributions to the electroweak corrections: Vertices (long-dashed), self-energies (dashed), boxes (dotted), triangles (dash-dotted). The sum is shown as full line.
• Figure 2 : Sample diagrams for the virtual corrections. $\Gamma$ stands for all contributions from gauge boson, goldstone boson and Higgs exchange.
• Figure 2 : Comparison between the electroweak corrections: with the $Z$ and $\chi$ triangle diagrams included (full) and without these contributions (dashed).