%0 Journal Article %T Observation of gauge boson joint-polarisation states in W± Z production from pp collisions at √s=13 TeV with the ATLAS detector %A ATLAS Collaboration (Aad, G. et al %A Amos, K. R. %A Aparisi Pozo, J. A. %A Bailey, A. J. %A Bouchhar, N. %A Cabrera Urban, S. %A Cantero, J. %A Cardillo, F. %A Castillo Gimenez, V. %A Chitishvili, M. %A Costa, M. J. %A Didenko %A Escobar, C. %A Fiorini, L. %A Fullana Torregrosa, E. %A Fuster, J. %A Garcia, C. %A Garcia Navarro, J. E. %A Gomez Delegido, A. J. %A Gonzalez de la Hoz, S. %A Gonzalvo Rodriguez, G. R. %A Guerrero Rojas, J. G. R. %A Higon-Rodriguez, E. %A Lacasta, C. %A Lozano Bahilo, J. J. %A Marti-Garcia, S. %A Martinez Agullo, P. %A Miralles Lopez, M. %A Mitsou, V. A. %A Monsonis Romero, L. %A Moreno Llacer, M. %A Munoz Perez, D. %A Navarro-Gonzalez, J. %A Poveda, J. %A Prades Ibañez, A. %A Rubio Jimenez, A. %A Ruiz-Martinez, A. %A Sabatini, P. %A Salt, J. %A Sanchez Sebastian, V. %A Sayago Galvan, I. %A Senthilkumar, V. %A Soldevila, U. %A Sanchez, J. %A Torro Pastor, E. %A Valero, A. %A Valls Ferrer, J. A. %A Varriale, L. %A Villaplana Perez, M. %A Vos, M. %J Physics Letters B %D 2023 %V 843 %I Elsevier %@ 0370-2693 %G English %F ATLASCollaborationAad_etal2023 %O WOS:001057207200001 %O exported from refbase (https://references.ific.uv.es/refbase/show.php?record=5800), last updated on Mon, 04 Dec 2023 14:52:20 +0000 %X Measurements of joint-polarisation states of Wand Zgauge bosons in W +/- Z production are presented. The data set used corresponds to an integrated luminosity of 139fb(-1) of proton-proton collisions at a centre-of-mass energy of 13TeV recorded by the ATLAS detector at the CERN Large Hadron Collider. The W +/- Z candidate events are reconstructed using leptonic decay modes of the gauge bosons into electrons and muons. The simultaneous pair-production of longitudinally polarised vector bosons is measured for the first time with a significance of 7.1 standard deviations. The measured joint helicity fractions integrated over the fiducial region are f(00)= 0.067 +/- 0.010, f(0T) = 0.110 +/- 0.029, f(T0) = 0.179 +/- 0.023 and f(TT) = 0.644 +/- 0.032, in agreement with the next-to-leading-order Standard Model predictions. Individual helicity fractions of the Wand Zbosons are also measured and found to be consistent with joint helicity fractions within the expected amounts of correlation. Both the joint and individual helicity fractions are also measured separately in W+Z and W-Z events. Inclusive and differential cross sections for several kinematic observables sensitive to polarisation are presented. %R 10.1016/j.physletb.2023.137895 %U https://arxiv.org/abs/2211.09435 %U https://doi.org/10.1016/j.physletb.2023.137895 %P 137895-27pp