Measurement of the tt¯Z and tt¯W cross sections in proton-proton collisions at s√=13 TeV with the ATLAS detector Aaboud, M. Aguilar Saavedra, Juan Antonio Atlas Collaboration A measurement of the associated production of a top-quark pair (tt¯) with a vector boson (W, Z) in proton-proton collisions at a center-of-mass energy of 13 TeV is presented, using 36.1 fb−1 of integrated luminosity collected by the ATLAS detector at the Large Hadron Collider. Events are selected in channels with two same- or opposite-sign leptons (electrons or muons), three leptons or four leptons, and each channel is further divided into multiple regions to maximize the sensitivity of the measurement. The tt¯Z and tt¯W production cross sections are simultaneously measured using a combined fit to all regions. The best-fit values of the production cross sections are σtt¯Z=0.95±0.08stat.±0.10syst. pb and σtt¯W=0.87±0.13stat.±0.14syst. pb in agreement with the Standard Model predictions. The measurement of the tt¯Z cross section is used to set constraints on effective field theory operators which modify the tt¯Z vertex. 2020-03-09T09:03:50Z 2020-03-09T09:03:50Z 2019-04-29 info:eu-repo/semantics/article Aaboud, M., Aad, G., Abbott, B., Abbott, D. C., Abdinov, O., Abeloos, B., ... & Abramowicz, H. (2019). Measurement of the t t¯ Z and t t¯ W cross sections in proton-proton collisions at s= 13 TeV with the ATLAS detector. Physical Review D, 99(7), 072009. http://hdl.handle.net/10481/60113 10.1103/PhysRevD.99.072009 eng http://creativecommons.org/licenses/by/3.0/es/ info:eu-repo/semantics/openAccess Atribución 3.0 España American Physical Society