Stress testing the vector-boson-fusion approximation in multijet final states

Francisco Campanario,Malin Sjödahl,Simon Plätzer,Peter Schichtel,Michael Rauch,Terrance M Figy

doi:10.1103/physrevd.98.033003

Abstract

We consider electro-weak Higgs plus three jets production at NLO QCD beyond strict VBF acceptance cuts. We investigate, for the first time, how accurate the VBF approximation is in these regions and within perturbative uncertainties, by a detailed comparison of full and approximate calculations. We find that a rapidity gap between the tagging jets guarantees a good approximation, while an invariant mass cut alone is not sufficient, which needs to be confronted with experimental choices. We also find that a significant part of the QCD corrections can be attributed to Higgs-Strahlungs-type topologies.

Highlights

INTRODUCTIONCollaborations announced the discovery of a new boson in the mass range of 125–126 GeV [3,4]
In 2012, both the ATLAS [1] and CMS [2]Collaborations announced the discovery of a new boson in the mass range of 125–126 GeV [3,4]
To studying the differences between the exact and the approximate calculations, we have investigated the effect of quantum chromodynamics (QCD) corrections subject to tight vector-boson fusion (VBF) cuts, implemented by requesting a rapidity gap of Δy12 > 3 and a invariant mass of m12 > 600 GeV for two tagged jets

Summary

INTRODUCTION

Collaborations announced the discovery of a new boson in the mass range of 125–126 GeV [3,4]. A veto on central QCD activity is sometimes applied to enrich the contribution of the color singlet vector boson exchange [30,31,32,33,34,35]. Theoretical predictions in this region often employ the so-called VBF approximation, where only the t-channel topology is kept and s-channel contributions as well as interference effects between different topologies are. We quantify the reliability of the VBF approximation, i.e., the neglection of the diagrams which are not of the VBF t-channel topology along with interference effects with u-channel topologies

OUTLINE OF THE CALCULATION

IMPACT OF QCD CORRECTIONS

EFFECTS OF Δy12 AND m12 SELECTIONS

Findings

CONCLUSIONS AND OUTLOOK