NLO QCD corrections to WW+jet production including leptonic W decays at hadron colliders

TL;DR

This paper presents the calculation of next-to-leading order QCD corrections to WW+jet production at hadron colliders, including leptonic W decays, improving the accuracy of background predictions for Higgs and new physics searches.

Contribution

It introduces an improved narrow-width approximation for leptonic W decays in NLO QCD calculations of WW+jet production at colliders.

Findings

QCD corrections stabilize the total cross section predictions.

Differential cross sections are significantly distorted by NLO corrections.

The shape of distributions changes notably when additional energy scales are involved.

Abstract

We report on the calculation of the next-to-leading order QCD corrections to the production of W-boson pairs in association with a hard jet at the Tevatron and the LHC, which is an important source of background for Higgs and new-physics searches. Leptonic decays of the W bosons are included by applying an improved version of the narrow-width approximation that treats the W bosons as on-shell particles, but keeps the information on the W spin. A selection of differential NLO QCD cross sections is provided both for the LHC and the Tevatron. The QCD corrections stabilize the LO prediction for the cross section with respect to scale variations. The differential LO cross sections are generally not simply rescaled by the corrections. Their shapes are particularly distorted if an additional energy scale is involved.