Search for new phenomena in ttbar + heavy-flavour jets at √s =13 TeV with the ATLAS detector

A search for new phenomena in ttbar final states with additional heavy-flavour jets has been carried out using 13.2 fb-1 data of pp collisions at sqrt(s) = 13 TeV with the ATLAS detector at the LHC. The search targets a variety of signals, including the pair production of a vector-like top quark; four-top-quark production in several new physics scenarios. Data are analysed in the lepton-plus-jets final state as well as the jets-plus-ETmiss final state. The search exploits the high multiplicity of b-jets, the high scalar sum of transverse momenta of all final state objects, and the presence of boosted hadronically-decaying resonances reconstructed as large-radius jets, characteristic of signal events.