Title Measurement of the helicity fractions of **W** bosons from top quark decays using fully reconstructed $t\overline{t}$ events with CDF II Measurement of the helicity fractions of **W** bosons from top quark decays using fully reconstructed $t\overline{t}$ events with CDF II Author Abulencia, A. Van Remortel, N. et al. Faculty/Department Faculty of Sciences. Physics Publication type article Publication 2007 Lancaster, Pa , 2007 Subject Physics Source (journal) Physical review : D : particles and fields. - Lancaster, Pa, 1970 - 2003 Volume/pages 75(2007) :5 , p. 052001,1-052001,11 ISSN 0556-2821 ISI 000245333000003 Carrier E Target language English (eng) Full text (Publishers DOI) Affiliation University of Antwerp Abstract We present a measurement of the fractions F0 and F+ of longitudinally polarized and right-handed W bosons in top-quark decays using data collected with the CDF II detector. The data set used in the analysis corresponds to an integrated luminosity of approximately 318  pb-1. We select tt̅ candidate events with one lepton, at least four jets, and missing transverse energy. Our helicity measurement uses the decay angle θ*, which is defined as the angle between the momentum of the charged lepton in the W boson rest frame and the W momentum in the top-quark rest frame. The cos⁡θ* distribution in the data is determined by full kinematic reconstruction of the tt̅ candidates. We find F0=0.85-0.22+0.15(stat)±0.06(syst) and F+=0.05-0.05+0.11(stat)±0.03(syst), which is consistent with the standard model prediction. We set an upper limit on the fraction of right-handed W bosons of F+<0.26 at the 95% confidence level. Full text (open access) https://repository.uantwerpen.be/docman/irua/df3e6a/206e578c.pdf E-info http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000245333000003&DestLinkType=RelatedRecords&DestApp=ALL_WOS&UsrCustomerID=ef845e08c439e550330acc77c7d2d848 http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000245333000003&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=ef845e08c439e550330acc77c7d2d848 http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000245333000003&DestLinkType=CitingArticles&DestApp=ALL_WOS&UsrCustomerID=ef845e08c439e550330acc77c7d2d848 Handle