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

Abstract

We present measurements of the process pp^- →WZ+X→l'ν 'μ^- at √s=1.96TeV, where l and l' are electrons or muons. Using 1fb^-1 of data from the D∅ 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^+1.7pb. 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 =2TeV. 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.