Measurement of σ(pp̅→Z + X) Br(Z→τ⁺τ^-) at √s= 1.96 TeV

Abstract

We present a measurement of the cross section for Z boson production times the branching fraction to tau lepton pairs σ(pp̅→Z+X)Br(Z→τ⁺τ^-) in pp̅ collisions at √s= 1.96 TeV . The measurement is performed in the channel in which one tau lepton decays into a muon and neutrinos, and the other tau lepton decays hadronically or into an electron and neutrinos. The data sample corresponds to an integrated luminosity of 1.0 fb^-1 collected with the D0 detector at the Fermilab Tevatron Collider. The sample contains 1511 candidate events with an estimated 20% background from jets or muons misidentified as tau leptons. We obtain σ.Br=240±8(stat)±12(sys)±(lum) pb, which is consistent with the standard model prediction.