Threshold Resummed and Approximate NNLO results for W+W- Pair Production at the LHC

TL;DR

This paper combines advanced QCD calculations with threshold resummation to produce highly precise predictions for W+W- production cross sections at the LHC, reducing uncertainties and improving accuracy over previous models.

Contribution

It introduces the first approximate NNLO results for W+W- production at the LHC, incorporating soft-gluon resummation and leading singular terms for enhanced precision.

Findings

NNLL resummation increases the invariant mass distribution by ~3-4% in the peak region.

Approximate NNLO cross sections increase NLO results by 0.5-3%.

Uncertainties due to scale variation are minimized with threshold logarithm inclusion.

Abstract

The next-to-leading order (NLO) QCD radiative corrections to W+W- production at hadron colliders are well understood. We combine NLO perturbative QCD calculations with soft-gluon resummation of threshold logarithms to find a next-to-next-to leading logarithmic (NNLL) prediction for the total cross section and the invariant mass distribution at the LHC. We also obtain approximate next-to-next-to-leading order (NNLO) results for the total W+W- cross section at the LHC which includes all contributions from the scale dependent leading singular terms. Our result for the approximate NNLO total cross section is the most precise theoretical prediction available. Uncertainties due to scale variation are shown to be small when the threshold logarithms are included. NNLL threshold resummation increases the W+W- invariant mass distribution by ~ 3-4% in the peak region for both \sqrt{S}=8 and 14 TeV. The NNLL threshold resummed and approximate NNLO cross sections increase the NLO cross section by 0.5-3% for \sqrt{S}=7, 8, 13, and 14 TeV.