Measurement of the pp̅ → WZ + X cross section at √s =1.96 TeV and limits on WWZ trilinear gauge couplings

Authors

V. M. Abazov, Joint Institute for Nuclear Research, Dubna, Russia
Kenneth A. Bloom, University of Nebraska-LincolnFollow
Gregory R. Snow, University of Nebraska-LincolnFollow
D0 Collaboration

Date of this Version

12-21-2007

Comments

Published by American Physical Society. Phys. Rev. D 76, 111104(R) (2007). http://prd.aps.org. Copyright © 2007 American Physical Society. Used by permission.

Abstract

We present measurements of the process pp̅ → WZ + X → ℓ′νℓℓ&#; at √s = 1.96 TeV, where ℓ and ℓ′ are electrons or muons. Using 1 fb^-1 of data from the D0 experiment, we observe 13 candidates with an expected background of 4.5 ± 0.6 events and measure a cross section σ(WZ) = 2.7_-1.3^+1.7 pb. From the number of observed events and the Z boson transverse momentum distribution, we limit the trilinear WWZ gauge couplings to -0.17 ≤ λ_Z ≤ 0.21(Δκ_Z= 0) at the 95% C.L. for a form factor scale Λ = 2 TeV. Further, assuming that Δg₁^Z = Δκ_Z, we find -0.12 ≤ Δκ_Z≤0.29 (λ_Z= 0) at the 95% C.L. These are the most restrictive limits on the WWZ couplings available to date.