Measurement of σ(pp-bar→Z)⋅Br(Z→ττ) at s√=1.96 TeV

Abstract

We present a measurement of the cross section for Z production times the branching fraction to τ leptons, σ⋅Br(Z→τ(+)τ(−)), in pp¯ collisions at s√=1.96 TeV in the channel in which one τ decays into μνμντ, and the other into hadrons+ν(τ) or eν(e)ν(τ). The data sample corresponds to an integrated luminosity of 226 pb(−1) collected with the D0 detector at the Fermilab Tevatron collider. The final sample contains 2008 candidate events with an estimated background of 55%. From this we obtain σ⋅Br(Z→τ+τ−)=237±15(stat)±18(sys)±15(lum)pb, in agreement with the standard model prediction.