Measurement of b-quark Pair Production, in association with Z bosons and Top quarks, with the ATLAS Detector

This thesis uses 36.1 fb$^{−1}$of proton-proton collision data collected with the ATLAS detector situated at the Large Hadron Collider at √s = 13 TeV to measure the associated production of Z bosons with b-quark jets. The differential and fiducial cross-sections for events containing a Z boson with 1 and 2 additional b-quark-jets are measured and compared with leading and next-to-leading order theoretical predictions An additional measurement of b-quark production in association with top quarks is pre-sented. This analysis only used events with either 1 or 2 leptons in the final state. It also made no attempt at identifying the source of the b-quark jets. A forthcoming analysis will identify the source of b-quark jets to measure differential properties, and some studies for this analysis are presented. Lastly, in response to future increases to the instantaneous luminosity by the Large Hadron Collider the ATLAS collaboration is now preparing to revamp the inner detector. Performance results as well as a new algorithm for finding photon conversions is presented.