Top Quark Pair Production beyond NNLO

TL;DR

This paper develops an approximate N$^3$LO calculation for top quark pair production cross sections, combining resummation techniques and analyticity in Mellin space, validated against known NNLO results.

Contribution

It introduces a novel method to estimate N$^3$LO corrections for heavy quark production using Mellin space analyticity and resummation insights, extending previous Higgs production techniques.

Findings

N$^3$LO corrections increase the cross section by about 4% at the LHC.

The method is validated against existing NNLO results, showing good agreement.

Provides a new approach for higher-order QCD calculations in heavy quark production.

Abstract

We construct an approximate expression for the total cross section for the production of a heavy quark-antiquark pair in hadronic collisions at next-to-next-to-next-to-leading order (N$^3$LO) in $\alpha_s$. We use a technique which exploits the analyticity of the Mellin space cross section, and the information on its singularity structure coming from large N (soft gluon, Sudakov) and small N (high energy, BFKL) all order resummations, previously introduced and used in the case of Higgs production. We validate our method by comparing to available exact results up to NNLO. We find that N$^3$LO corrections increase the predicted top pair cross section at the LHC by about 4% over the NNLO.