Measurement of the t(t)over-bar production cross section and top quark mass extraction using dilepton events in p(p)over-bar collisions
Abstract
We present a measurement of the top quark pair production cross section in p (p) over bar collisions at root s = 1.96 TeV using approximately 1 fb(-1) collected with the DO detector. We consider decay channels containing two high p(T) charged leptons where one lepton is identified as an electron or a muon while the other lepton can be an electron, a muon or a hadronically decaying tau lepton.
For a mass of the top quark of 170 GeV, the measured cross section is 7.5(-1.0)( 1.0)(stat)(-0.6)( 0.7)(syst)(-0.5)( 0.6)(lumi) pb. Using l tau events only, we measure: sigma(t (t) over bar) x B(t (t) over bar -} l tau b (b) over bar) = 0.13(-0.08)( 0.09)(stat)(-0.06)( 0.06)(syst)(-0.02)( 0.02)(lumi) pb.
Comparing the measured cross section as a function of the mass of the top quark with a partial next-to-next-to leading order Quantum Chromodynamics theoretical prediction, we extract a mass of the top quark of 171.5(-8.8)( 9-9) GeV, in agreement with direct measurements.