Measurement of the ttbar production cross section using dilepton events in ppbar collisions

TL;DR

This paper reports a precise measurement of the top-antitop quark pair production cross section in proton-antiproton collisions at 1.96 TeV, using dilepton events, and finds results consistent with the Standard Model predictions.

Contribution

First measurement of ttbar cross section in dilepton final states at Tevatron with high precision, confirming Standard Model expectations.

Findings

Measured cross section: 7.36 pb with 8% uncertainty

Combined cross section: 7.56 pb consistent with theory

Achieved precision comparable to theoretical calculations

Abstract

We present a measurement of the ttbar production cross section sigma(ttbar) in ppbar collisions at sqrt{s} = 1.96 TeV using 5.4 fb-1 of integrated luminosity collected with the D0 detector. We consider final states with at least two jets and two leptons (ee, emu, mumu), and events with one jet for the the emu final state as well. The measured cross section is sigma(ttbar)= 7.36 +0.90-0.79 (stat + syst) pb. This result combined with the cross section measurement in the lepton + jets final state yields sigma(ttbar)=7.56 +0.63-0.56 (stat + syst) pb, which agrees with the standard model expectation. The relative precision of 8% of this measurement is comparable to the latest theoretical calculations.