%0 Journal Article
%T Measurement of the polarisation of W bosons produced in top-quark decays using dilepton events at √s=13TeV with the ATLAS experiment
%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:001057197500001
%O exported from refbase (https://references.ific.uv.es/refbase/show.php?record=5793), last updated on Mon, 04 Dec 2023 07:37:32 +0000
%X A measurement of the polarisation of Wbosons produced in top-quark decays is presented, using proton-proton collision data at a centre-of-mass energy of v s= 13TeV. The data were collected by the ATLAS detector at the Large Hadron Collider and correspond to an integrated luminosity of 139fb(-1). The measurement is performed selecting t tevents decaying into final states with two charged leptons (electrons or muons) and at least two b-tagged jets. The polarisation is extracted from the differential cross-section distribution of the cos theta* variable, where theta(*) is the angle between the momentum direction of the charged lepton from the Wboson decay and the reversed momentum direction of the b-quark from the top-quark decay, both calculated in the Wboson rest frame. Parton-level results, corrected for the detector acceptance and resolution, are presented for the cos theta* angle. The measured fractions of longitudinal, left- and right-handed polarisation states are found to be f(0) = 0.684 +/- 0.005 (stat.)+/- 0.014 (syst.), f(L)= 0.318 +/- 0.003 (stat.)+/- 0.008 (syst.) and f(R)=-0.002 +/- 0.002 (stat.)+/- 0.014 (syst.), in agreement with the Standard Model prediction.
%R 10.1016/j.physletb.2023.137829
%U https://arxiv.org/abs/2209.14903
%U https://doi.org/10.1016/j.physletb.2023.137829
%P 137829-22pp