Measurement of the \(t\bar{t}Z\) and \(t\bar{t}W\) production cross sections in multilepton final states using 3.2 fb\(^{-1}\) of \(pp\) collisions at \(\sqrt{s}\) =13 TeV with the ATLAS detector

Abstract

A measurement of the \(t\bar{t}Z\) and \(t\bar{t}W\) production cross sections in final states with either two same-charge muons, or three or four leptons (electrons or muons) is presented. The analysis uses a data sample of proton-proton collisions at \(\sqrt{s} = 13\) TeV recorded with the ATLAS detector at the Large Hadron Collider in 2015, corresponding to a total integrated luminosity of 3.2 fb\(^{-1}\), The inclusive cross sections are extracted using likelihood fits to signal and control regions, resulting in \(\sigma_{t\bar{t}Z} = 0.9 \pm 0.3\) pb and \(\sigma_{t\bar{t}W} = 1.5 \pm 0.8\) pb, in agreement with the Standard Model predictions.