# Measurement of the top quark-pair production cross section with ATLAS in pp collisions at $\sqrt{s}=7\TeV$

Abstract : A measurement of the production cross-section for top quark pairs($\ttbar$) in $pp$ collisions at $\sqrt{s}=7 \TeV$ is presented using data recorded with the ATLAS detector at the Large Hadron Collider. Events are selected in two different topologies: single lepton (electron $e$ or muon $\mu$) with large missing transverse energy and at least four jets, and dilepton ($ee$, $\mu\mu$ or $e\mu$) with large missing transverse energy and at least two jets. In a data sample of 2.9 pb-1, 37 candidate events are observed in the single-lepton topology and 9 events in the dilepton topology. The corresponding expected backgrounds from non-$\ttbar$ Standard Model processes are estimated using data-driven methods and determined to be $12.2 \pm 3.9$ events and $2.5 \pm 0.6$ events, respectively. The kinematic properties of the selected events are consistent with SM $\ttbar$ production. The inclusive top quark pair production cross-section is measured to be $\sigmattbar=145 \pm 31 ^{+42}_{-27}$ pb where the first uncertainty is statistical and the second systematic. The measurement agrees with perturbative QCD calculations.
Document type :
Journal articles

http://hal.in2p3.fr/in2p3-00553524
Contributor : Claudine Bombar <>
Submitted on : Friday, January 7, 2011 - 3:01:14 PM
Last modification on : Wednesday, September 16, 2020 - 4:23:20 PM

### Citation

G. Aad, L. Aperio Bella, B. Aubert, M. Aurousseau, N. Berger, et al.. Measurement of the top quark-pair production cross section with ATLAS in pp collisions at $\sqrt{s}=7\TeV$. European Physical Journal C: Particles and Fields, Springer Verlag (Germany), 2011, 71, pp.1577. ⟨10.1140/epjc/s10052-011-1577-6⟩. ⟨in2p3-00553524⟩

Record views