Measurement of the top-quark pair production cross-section using final states with an electron or a muon and a hadronically decaying τ-lepton

Abstract

A measurement of the top-quark pair production cross-section is reported using proton-proton collision data at s=7 TeV recorded by ATLAS experiment at the Large Hadron Collider. Events are extracted from 2.05 fb−1 of data by requiring an isolated electron or muon, a large missing transverse momentum, two or more energetic jets and a hadronically decaying τ-lepton. The measured cross-section, σtt¯=186±13(stat.)±20(syst.)±7(lumi.) pb, is in good agreement with the Standard Model prediction.