We present an analysis of top-antitop quark production and decay into a tau lepton, tau neutrino, and bottom quark using data from 9fb-1 of integrated luminosity at the Collider Detector at Fermilab. Dilepton events, where one lepton is an energetic electron or muon and the other a hadronically decaying tau lepton, originating from proton-antiproton collisions at s=1.96TeV, are used. A top-antitop quark production cross section of 8.1±2.1pb is measured, assuming standard-model top quark decays. By separately identifying for the first time the single-tau and the ditau components, we measure the branching fraction of the top quark into the tau lepton, tau neutrino, and bottom quark to be (9.6±2.8)%. The branching fraction of top quark decays into a charged Higgs boson and a bottom quark, which would imply violation of lepton universality, is limited to be less than 5.9% at a 95% confidence level [for B(H-→τν̄)=1]. © 2014 American Physical Society.
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1103/PhysRevD.89.091101|
|Codice identificativo ISI:||WOS:000335829100001|
|Codice identificativo Scopus:||2-s2.0-84900858956|
|Titolo:||Study of top quark production and decays involving a tau lepton at CDF and limits on a charged Higgs boson contribution|
|Appare nelle tipologie:||1.1 Articolo in rivista|