  The search for first top-quark pair candidate events and the related
background studies using data-driven techniques are reported for about 300
inverse nb of 7 TeV proton-proton collision data delivered by the Large Hadron
Collider (LHC) and collected with the ATLAS detector. Selected events are
characterized by the presence of high-pT isolated charged lepton(s), high jet
multiplicity, jet(s) identified as originating from b-quark by a secondary
vertex tagger algorithm, and missing transverse energy. They reveal kinematics
properties consistent with top pair production.
