Recent results on associated vector boson production with the ATLAS and CMS experiments

Sofia Chouridou

doi:10.1051/epjconf/20159004004

Abstract

Several aspects of the associated vector boson production in pp collisions at √s = 7 TeV and √s = 8 TeV at the LHC have been recently investigated by the ATLAS and CMS collaborations. The production cross sections of the W and Z bosons in association with jets, as well as their ratio and the double differential cross section in the Z + jets final state are presented. Measurements of the cross sections of a vector boson (W or Z) in association with heavy flavour jets (b, c) and a top quark pair are also described. The measured cross sections are compared to expectations based on next-to-leading order QCD calculations as well as on Monte Carlo simulations.

Highlights

Precision measurements of associated vector boson production at the LHC [1] at a center-of-mass energy of √s = 7 TeV and √s = 8 TeV have been possible by the ATLAS [2] and CMS [3] collaborations due to the large data samples accumulated in 2011 and 2012
This study provides direct access to the strange quark content of the proton at an energy scale of the order of the W-boson mass
The production cross section of a top quark-antiquark pair ( ) in association with a W or Z boson has been measured using data collected at √s = 8 TeV during 2012 that correspond to an integrated luminosity of 20.3 fb-1 (ATLAS) and 19.5 fb-1 (CMS) [32-33]

Summary

Introduction

Precision measurements of associated vector boson production at the LHC [1] at a center-of-mass energy of √s = 7 TeV and √s = 8 TeV have been possible by the ATLAS [2] and CMS [3] collaborations due to the large data samples accumulated in 2011 and 2012. These measurements include the production cross sections of the W and Z bosons in association with jets, the ratio of W + jets to Z + jets cross sections (Rjets), the double differential cross section in the Z + jets final state, the cross sections of a vector boson (W or Z) in association with heavy flavour jets (b, c) as well as with a top quark pair These measurements are useful for the validation of the pQCD calculations and can constrain the PDF of the proton. They constitute important backgrounds for other Standard Model (SM) processes and for searches beyond the SM

W and Z production in association with jets

W and Z production in association with a top quark pair

Conclusions