NLO QCD corrections to W-b-bbar and Z-b-bbar production

TL;DR

This paper calculates NLO QCD corrections for W/Z boson production with bottom quark pairs, including full bottom-quark mass effects, significantly improving the accuracy of cross-section predictions and invariant mass distributions.

Contribution

It provides the first comprehensive NLO QCD analysis of W/Z + bottom quark pairs including bottom-quark mass effects at the Tevatron.

Findings

NLO corrections reduce scale dependence of the cross-section.

Bottom-quark mass effects contribute 8-10% to the total cross-section.

Mass effects influence the invariant mass distribution shape, especially at low mass.

Abstract

We present NLO QCD results for W/Z gauge boson production with bottom quark pairs at the Tevatron including full bottom-quark mass effects. We study the impact of QCD corrections on both total cross-section and invariant mass distribution of the bottom-quark pair. Including NLO QCD corrections greatly reduces the dependence of the tree-level cross-section on the renormalization and factorization scales. We also compare our calculation to a calculation that considers massless bottom quarks and find that the bottom-quark mass effects amount to about 8-10% of the total NLO QCD cross-section and can impact the shape of the bottom-quark pair invariant mass distribution, in particular in the low invariant mass region.