One of the important tests of the SM is the measurement of the top quark Yukawa coupling, directly measured via the associated production process pp→ttH. Both ATLAS and CMS have performed searches of ttH targeting the most relevant Higgs decays modes in final states with high lepton multiplicity, high b-jet multiplicity, or containing two photons at √s=13 TeV. In this talk, the latest results on the search for the ttH process in the multilepton final state with the ATLAS experiment will be discussed, together with a detailed study of one of the main background processes, ttW, and unexpected tensions observed in data.
Short bio: Tamara was born in Argentina, studied Physics in the University of La Laguna, Tenerife, Spain, and did her PhD on top quark physics in the University of Göttingen, Germany. She worked as a post- doc with the University of McGill, Montreal, Canada, and she is a CERN Research Fellow since 2018. She is currently leading the ttH and tH analyses within the ATLAS Collaboration.