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The ATLAS and CMS detectors each accumulated data with an an integrated luminosity of 140 fb−1, during the LHC Run-II from 2015 to 2018. This large amount of data provides a foundation to study the physics of the heaviest elementary particles, such as the Higgs boson and the top quark, with unprecedented precision. Additionally, these studies provided the opportunity to search for physics beyond the standard model (BSM), that may reveal itself in modifications of the top quark couplings. There is still a lot of room for new discoveries: tVV processes consist of a single top quark and two heavy vector bosons and have not been observed yet. With the upcoming LHC Run-III between 2021 and 2024, the size of the data sets will double to an integrated luminosity of about 300 fb−1. This large amount of data might be enough to observe specific tVV processes and study their sensitivity to BSM phenomena. Among the tVV processes, tWZ is the most promising candidate for a LHC Run-III cross section measurement. It is possible to discriminate the process from its main backgrounds using dedicated event selections and by separating off the leading backgrounds with a multivariate classifier (MVA). The results of the MVA were used to obtain the cross section and the associated uncertainties. Furthermore, the tWZ process is sensitive to many BSM effects in the electroweak sector, which are parametrized in the context of SM effective field theory by Wilson coefficients of operators with mass dimension 6. Such operators affect the top quark couplings and the tWZ cross section measurements thus constrain many of the Wilson coefficients in novel ways. In this thesis I present the feasibility of the cross section measurement of the tVV processes at the LHC Run-III with data from the CMS experiment and present the projected sensitivity to anomalous top quark couplings. iii D ie a pp ro bi er te g ed ru ck te O rig in al ve rs io n di es er D ip lo m ar be it is t a n de r T U W ie n B ib lio th ek v er fü gb ar . T he a pp ro ve d or ig in al v er si on o f t hi s th es is is a va ila bl e in p rin t a t T U W ie n B ib lio th ek .

Cross section measurements of processes with a single top quark and two vector bosons with the CMS experiment