NNLO QCD corrections to $Wb\bar{b}$ production at the LHC

TL;DR

This paper presents the first NNLO QCD calculations for W-boson production with a bottom-quark pair at the LHC, improving theoretical precision and convergence for relevant collider observables.

Contribution

It introduces the first NNLO calculation for a 2→3 process with a massive external particle, using novel finite-field methods for two-loop amplitudes.

Findings

Improved perturbative convergence with NNLO corrections

Enhanced accuracy for inclusive and jet-vetoed cross sections

First analytic two-loop five-particle amplitude with massive external particle

Abstract

We compute theoretical predictions for the production of a W-boson in association with a bottom-quark pair at hadron colliders at next-to-next-to-leading order (NNLO) in QCD, including the leptonic decay of the W-boson, while treating the bottom quark as massless. This calculation constitutes the very first $2 \to 3$ process with a massive external particle to be studied at such a perturbative order. We derive an analytic expression for the required two-loop five-particle amplitudes in the leading colour approximation employing finite-field methods. Numerical results for the cross section and differential distributions are presented for the Large Hadron Collider at $\sqrt{s} = 8$ TeV. We observe an improvement of the perturbative convergence for the inclusive case and for the prediction with a jet veto upon the inclusion of the NNLO QCD corrections.