TY - JOUR AU - ATLAS Collaboration (Aad, G. et al AU - Alvarez Piqueras, D. AU - Cabrera Urban, S. AU - Castillo Gimenez, V. AU - Costa, M. J. AU - Fernandez Martinez, P. AU - Ferrer, A. AU - Fiorini, L. AU - Fuster, J. AU - Garcia, C. AU - Garcia Navarro, J. E. AU - Gonzalez de la Hoz, S. AU - Hernandez Jimenez, Y. AU - Higon-Rodriguez, E. AU - Irles Quiles, A. AU - Jimenez Pena, J. AU - Kaci, M. AU - King, M. AU - Lacasta, C. AU - Lacuesta, V. R. AU - Marti-Garcia, S. AU - Mitsou, V. A. AU - Pedraza Lopez, S. AU - Perez Garcia-Estañ, M. T. AU - Romero Adam, E. AU - Ros, E. AU - Salt, J. AU - Sanchez Martinez, V. AU - Soldevila, U. AU - Sanchez, J. AU - Valero, A. AU - Valls Ferrer, J. A. AU - Vos, M. PY - 2015 DA - 2015// TI - Measurement of the t(t)over-barW and t(t)over-barZ production cross sections in pp collisions at root s=8 TeV with the ATLAS detector T2 - J. High Energy Phys. JO - Journal of High Energy Physics SP - 172 EP - 48pp VL - 11 IS - 11 PB - Springer KW - Electroweak interaction KW - Hadron-Hadron scattering KW - Top physics AB - The production cross sections of top-quark pairs in association with massive vector bosons have been measured using data from pp collisions at root s = 8 TeV. The dataset corresponds to an integrated luminosity of 20.3 fb(-1) collected by the ATLAS detector in 2012 at the LHC. Final states with two, three or four leptons are considered. A fit to the data considering the t (t) over barW and t (t) over barZ processes simultaneously yields a significance of 5.0 sigma (4.2 sigma) over the background-only hypothesis for t (t) over barW (t (t) over barZ) production. The measured cross sections are sigma(t (t) over barW) = 369(-91)(+100) fb and sigma(t (t) over barZ) = 176(-52)(+58) fb. The background-only hypothesis with neither t (t) over barW nor t (t) over barZ production is excluded at 7.1 sigma. All measurements are consistent with next-to-leading-order calculations for the t (t) over barW and t (t) over barZ processes. SN - 1029-8479 UR - http://arxiv.org/abs/1509.05276 UR - https://doi.org/10.1007/JHEP11(2015)172 DO - 10.1007/JHEP11(2015)172 LA - English N1 - WOS:000366139900001 ID - ATLASCollaborationAad_etal2015 ER -