W+3 jet production at the LHC as a signal or background

TL;DR

This work delivers a detailed NLO QCD study of W+3 jet production at the LHC using a leading-color approximation with color adjustment, examining both signal-like and background-like cuts. It shows that NLO corrections dramatically reduce the renormalization/factorization scale uncertainty for total cross sections and that differential distributions can experience sizable, region-dependent corrections sensitive to jet kinematics and scale choices. The authors compare LO predictions—especially those using local, event-by-event scales and MLM matching—to NLO shapes, finding good agreement in many distributions after normalization, while highlighting large, cut-dependent differences between ATLAS and CMS SUSY-like analyses. These results emphasize the necessity of true NLO calculations for reliable background modeling in SUSY searches and motivate extending such studies to additional multi-jet backgrounds.

Abstract

We discuss the production of W bosons in association with three jets at the LHC. We investigate how next-to-leading order QCD corrections modify basic kinematic distributions of jets and leptons. We also address the magnitude of NLO QCD effects in W+3 jet observables, relevant for SUSY searches at the LHC.

Figures (13)

• Figure 1: The dependence of the $W^++3~{\rm jet}$ inclusive production cross section at the LHC on the factorization and renormalization scale $\mu$. All cuts and parameters are described in the text. The leading color adjustment procedure is applied.
• Figure 2: The dependence of the $W^-+3~{\rm jet}$ inclusive production cross section at the LHC on the factorization and renormalization scale $\mu$. All cuts and parameters are described in the text. The leading color adjustment procedure is applied.
• Figure 3: The transverse momentum distribution of the leading jet for $W^++3~{\rm jet}$ inclusive production cross section at the LHC. All cuts and parameters are described in the text. The leading color adjustment procedure is applied.
• Figure 4: The transverse momentum distribution of the leading jet for $W^++3~{\rm jet}$ inclusive production cross section at the LHC. All cuts and parameters are described in the text. The leading color adjustment procedure is applied. All LO distributions are rescaled by constant factor, to ensure that the LO and NLO normalizations coincide.
• Figure 5: The transverse momentum distribution of the second hardest jet in $W^++3$ jet production at the LHC. All cuts and parameters are described in the text. The leading color adjustment procedure is applied. The LO distribution is rescaled by constant factor, to ensure that the LO and NLO normalizations coincide.