NLO QCD corrections to pp/ppbar --> WW+jet+X including leptonic W-boson decays

TL;DR

This work computes the next-to-leading order QCD corrections to pp/pbarp -> WW + jet + X, including leptonic W decays with spin information via an improved narrow-width approximation. It analyzes the LO and NLO structure across Tevatron and LHC, neglecting external bottom-quark contributions and emphasizing spin correlations in W decays. The results show that NLO corrections stabilize the total cross section against scale variations, but the reduction in scale dependence at the LHC depends on vetoing a second hard jet, with differential distributions affected nontrivially by additional energy scales. By providing differential cross sections and benchmarking virtual corrections, the study advances precise background predictions essential for Higgs and new-physics searches and supports future NNLO WW-related calculations.

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. Contributions from external bottom quarks are neglected, because they are either numerically suppressed or should be attributed to different processes such as Wt or ttbar production. A survey of differential NLO QCD cross sections is provided both for the LHC and the Tevatron. The QCD corrections stabilize the leading-order prediction for the cross section with respect to scale variations. However, the scale dependence of the next-to-leading order results for the LHC is only reduced considerably if a veto against the emission of a second hard jet is applied. In general, the corrections do not simply rescale the differential leading-order cross sections. In particular, their shapes are distorted if an additional energy scale is involved.

Figures (1)

• Figure 1: Schematic diagram for the process $ab\to {\rm V}$ V$X\to f\bar{f}' X$.