Measurement of the W boson polarization in top quark decays with the ATLAS detector

0388401 - FZÚ 2013 RIV US eng J - Journal Article
Aad, G. - Abbott, B. - Abdallah, J. - Böhm, Jan - Chudoba, Jiří - Gallus, Petr - Gunther, Jaroslav - Jakoubek, Tomáš - Juránek, Vojtěch - Kepka, Oldřich - Kupčo, Alexander - Kůs, Vlastimil - Lokajíček, Miloš - Marčišovský, Michal - Mikeštíková, Marcela - Myška, Miroslav - Němeček, Stanislav - Růžička, Pavel - Schovancová, Jaroslava - Šícho, Petr - Staroba, Pavel - Svatoš, Michal - Taševský, Marek - Tic, Tomáš - Valenta, J. - Vrba, Václav - Zeman, Martin … Total 2868 authors
Measurement of the W boson polarization in top quark decays with the ATLAS detector.
Journal of High Energy Physics. Roč. 2012, č. 6 (2012), s. 1-45. ISSN 1126-6708
R&D Projects: GA MŠMT LA08032
Institutional research plan: CEZ:AV0Z10100502
Keywords : ATLAS * LHC * top quark * W boson polarization * anomalous W tb couplings
Subject RIV: BF - Elementary Particles and High Energy Physics
Impact factor: 5.618, year: 2012
http://arxiv.org/abs/arXiv:1205.2484

This paper presents measurements of the polarization of W bosons in top quark decays, derived from ttbar events with missing transverse momentum, one charged lepton and at least four jets, or two charged leptons and at least two jets. Data from pp collisions at a centre-of-mass energy of 7 TeV were collected with the ATLAS experiment at the LHC and correspond to an integrated luminosity of 1.04 fb^-1. The measured fractions of longitudinally, left- and right-handed polarization are F_0=0.67+/-0.07, F_L=0.32+/-0.04 and F_R=0.01+/-0.05, in agreement with the Standard Model predictions. As the polarization of the W bosons in top quark decays is sensitive to the Wtb vertex Lorentz structure and couplings, the measurements were used to set limits on anomalous contributions to the Wtb couplings.
Permanent Link: http://hdl.handle.net/11104/0217295