Please use this identifier to cite or link to this item:
|Scopus||Web of Science®||Altmetric|
|Title:||Measurement of the W boson polarisation in tt¯ events from pp collisions at √s = 8 TeV in the lepton + jets channel with ATLAS|
|Other Titles:||Measurement of the W boson polarisation in tt -bar events from pp collisions at root s = 8 TeV in the lepton + jets channel with ATLAS|
|Citation:||European Physical Journal C, 2017; 77(4):264-1-264-28|
|M. Aaboud ... P. Jackson ... L. Lee ... A. Petridis ... M.J. White ... [et al.] (The ATLAS Collaboration)|
|Abstract:||This paper presents a measurement of the polarisation of W bosons from t¯t decays, reconstructed in events with one high-pT lepton and at least four jets. Data from pp collisions at the LHC were collected at √s = 8 TeV and correspond to an integrated luminosity of 20.2 fb⁻¹. The angle θ* between the b-quark from the top quark decay and a direct W boson decay product in the W boson rest frame is sensitive to the W boson polarisation. Two different W decay products are used as polarisation analysers: the charged lepton and the down-type quark for the leptonically and hadronically decaying W boson, respectively. The most precise measurement of the W boson polarisation via the distribution of cos θ* is obtained using the leptonic analyser and events in which at least two of the jets are tagged as b-quark jets. The fitted fractions of longitudinal, left- and right-handed polarisation states are F0 = 0.709 ± 0.019, FL = 0.299 ± 0.015 and FR = −0.008 ± 0.014, and are the most precisely measured W boson polarisation fractions to date. Limits on anomalous couplings of the Wtb vertex are set.|
|Rights:||© CERN for the benefit of the ATLAS collaboration 2017. This article is an open access publication|
|Appears in Collections:||Physics publications|
Files in This Item:
There are no files associated with this item.
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.