Abstract
© 2014 CERN, for the ATLAS Collaboration. This article presents measurements of the t-channel single top-quark (t) and top-antiquark (tÀ) total production cross sections _(tq) and _(tÀq), their ratio Rt=_(tq)/_(tÀq), and a measurement of the inclusive production cross section _(tq+tÀq) in proton-proton collisions at s=7TeV at the LHC. Differential cross sections for the tq and tÀq processes are measured as a function of the transverse momentum and the absolute value of the rapidity of t and tÀ, respectively. The analyzed data set was recorded with the ATLAS detector and corresponds to an integrated luminosity of 4.59fb-1. Selected events contain one charged lepton, large missing transverse momentum, and two or three jets. The cross sections are measured by performing a binned maximum-likelihood fit to the output distributions of neural networks. The resulting measurements are _(tq)=46±1(stat)±6(syst)pb, _(tÀq)=23±1(stat)±3(syst)pb, Rt=2.04±0.13(stat)±0.12(syst), and _(tq+tÀq)=68±2(stat)±8(syst)pb, consistent with the Standard Model expectation. The uncertainty on the measured cross sections is dominated by systematic uncertainties, while the uncertainty on Rt is mainly statistical. Using the ratio of _(tq+tÀq) to its theoretical prediction, and assuming that the top-quark-related CKM matrix elements obey the relation |Vtb|_|Vts|,|Vtd|, we determine |Vtb|=1.02±0.07.