Differential cross-section measurements of $WbWb$ production in the lepton+jets channel at $\sqrt{s}$ = 13 TeV with the ATLAS detector

The top quark provides a unique opportunity to test the Standard Model of particle physics. Its heavy mass causes it to decay before it can hadronize, allowing for the study of the properties of a bare quark. This thesis presents differential cross-section measurements stemming from various top quark processes. This measurement is conducted in the presently uncovered semileptonic channel, where one W boson decays leptonically and the other decays hadronically. The analysis is motivated by the need to improve the modeling of the interference effects between singly-resonant and doubly-resonant top quark decays. This effect has been the source of significant modeling uncertainties in other top-sector analyses. The data and simulation used to perform this analysis correspond to the full ATLAS Run 2 dataset, collected 2015-2018. This data corresponds to an integrated luminosity of 140 $fb^{-1}$ and a center of mass energy of $\sqrt{s}$ = 13 TeV. The measured cross-sections are compared to predictions using different combinations of MC generators. Together with a complementary analysis in the dileptonic channel, this thesis provides a means to constrain modeling uncertainties towards the development of an all-inclusive bb4l generator. This generator could model all top quark processes while accurately accounting for all interference effects.