Top quark pair properties: Spin correlation, charge asymmetry and complex final states at LHC in ATLAS

In proton-proton collisions at the LHC, pairs of top and anti-top quarks are expected to be mostly produced through gluon fusion, in contrast to production at the Tevatron, where quark annihilation dominates. Making use of the large number of top quark pairs, we present measurements of the spin correlation between top and anti-top quarks as well as of the top quark charge asymmetry, which constitute important tests of QCD and are sensitive to new physics. We also discuss top production in association of photons and Z bosons. (authors)