New results on $t\bar{t}W$ and 4-top production with the ATLAS experiment

The ATLAS experiment has performed extensive searches for rare Standard Model processes involving top quarks. In this contribution two recent highlights of this programme are presented. The top-quark pair production in association with a W boson is a difficult process to calculate and model and is one of the leading sources of same-sign and multi-lepton events. To improve our understanding of this process, a new inclusive and differential measurement of this process in events with 2 or 3 leptons was performed, as well as measurements of the ratio of ttW events with a positively and a negatively charged W-boson. The result confirms the slight tension observed in previous measurements. The 4-top production process, with a cross section of approximately 12 fb, is nearly one order of magnitude still. A re-analysis of the run 2 dataset is performed in the same-sign and multi-lepton channel, with several improvements in the event selection, the data-driven background estimate and the final discriminant. The cross section measurement of 23 +/- fb, is presented, as well as bounds on the top quark Yukawa coupling and on EFT operator coefficients affecting 4-top production.