ATLAS Collaboration2018-11-082018-11-082017-01-20Aaboud, M., Aad, G., Abbott, B. et al. Eur. Phys. J. C (2017) 77: 40. https://doi.org/10.1140/epjc/s10052-016-4574-yhttps://hdl.handle.net/1808/27265A measurement of the tt¯Z and tt¯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 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 σtt¯Z=0.9±0.3 pb and σtt¯W=1.5±0.8 pb, in agreement with the Standard Model predictions.© CERN for the benefit of the ATLAS collaboration 2017. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License, which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.https://creativecommons.org/licenses/by/4.0/Article10.1140/epjc/s10052-016-4574-yopenAccess