Top quark as a window to new physics: recent ATLAS results

The Large Hadron Collider proton-proton collision centre-of-mass energy was recently increased to 13 TeV, opening a unique window to search for signatures with mass scales higher than ever before and involving several high-mass particles. One attractive possibility is to focus on the heaviest known elementary particle described by the Standard Model, the top quark. With a mass close to the scale of electroweak symmetry breaking, the top quark is predicted to have a very large coupling to the Higgs boson and in many physics models beyond the Standard Model also to other new resonances. Possible new phenomena may enhance the SM cross-sections through the production of heavy objects in association with a top-quark pair. In this talk, I will present recent results from the ATLAS Collaboration which target a variety of scenarios and improve the sensitivity to a wider class of BSM processes.