Measurement of the top quark pair cross section with ATLAS in $pp$ collisions at $\sqrt{s} =$ 7 TeV using final states with an electron or a muon and a hadronically decaying $\tau$ lepton

ATLAS collaboration (2879 authors)Aguilar-Saavedra, Juan AntonioAnjos, NunoCantrill, RobertCarvalho, JoãoCastro, Nuno FilipeConde Muiño, PatriciaDo Valle Wemans, AndréFiolhais, MiguelGomes, AgostinhoGonçalo, RicardoJorge, PedroLopes, LourencoMachado Miguens, JoanaMaio, AméliaManeira, JoséOliveira, Miguel AlfonsoOnofre, AntónioPalma, AlbertoPina, João AntonioPinto, BelmiroSantos, HelenaSaraiva, JoãoSilva, JoséVeloso, FilipeWolters, Helmut2019-02-032019-02-032013-07-16http://dx.doi.org/10.1016/j.physletb.2012.09.032http://hdl.handle.net/10400.26/26174A measurement of the cross section of top quark pair production in proton-proton collisions recorded with the ATLAS detector at the LHC at a centre-of-mass energy of 7 TeV is reported. The data sample used corresponds to an integrated luminosity of 2.05 fb^-1. Events with an isolated electron or muon and a tau lepton decaying hadronically are used. In addition, a large missing transverse momentum and two or more energetic jets are required. At least one of the jets must be identified as originating from a b quark. The measured cross section, sigma_ttbar = 186+/- 13 (stat) +/- 20 (syst) +/- 7 (lum.) pb is in good agreement with the Standard Model prediction.engMeasurement of the top quark pair cross section with ATLAS in $pp$ collisions at $\sqrt{s} =$ 7 TeV using final states with an electron or a muon and a hadronically decaying $\tau$ leptonjournal article2019-02-03