Measurement of Wγ and Zγ production in pp collisions at s=7 TeV
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics, vol.701, no.5, pp.535-555, 2011 (SCI-Expanded, Scopus)
- Publication Type: Article / Article
- Volume: 701 Issue: 5
- Publication Date: 2011
- Doi Number: 10.1016/j.physletb.2011.06.034
- Journal Name: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
- Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
- Page Numbers: pp.535-555
- Keywords: CMS, Electroweak, Physics
- Yıldız Technical University Affiliated: No
Abstract
A measurement of W γ and Z γ production in proton-proton collisions at s=7 TeV is presented. Results are based on a data sample recorded by the CMS experiment at the LHC, corresponding to an integrated luminosity of 36 pb-1. The electron and muon decay channels of the W and Z are used. The total cross sections are measured for photon transverse energy ETγ>10 GeV and spatial separation from charged leptons in the plane of pseudorapidity and azimuthal angle ΔR(ℓ,γ)>0.7, and with an additional dilepton invariant mass requirement of Mℓℓ>50 GeV for the Z γ process. The following cross section times branching fraction values are found: σ(pp→Wγ+X)×B(W→ℓν)=56.3±5.0(stat.)±5.0(syst.)±2.3(lumi.) pb and σ(pp→Zγ+X)×B(Z→ℓℓ)=9.4±1.0(stat.)±0.6(syst.)±0.4(lumi.) pb. These measurements are in agreement with standard model predictions. The first limits on anomalous WW γ, ZZ γ, and Z γγ trilinear gauge couplings at s=7 TeV are set. © 2011 CERN.