[PDF] Top 20 Measurement of the W-boson helicity in top-quark decays from $t\bar{t}$ production in lepton+jets events in pp collisions at $\sqrt{s} =$ 7 TeV

... Science of the Russian Federation, the Federal Agency of Atomic Energy of the Russian Federation, Russian Academy of Sciences, and the Russian Foundation for Basic ... See full document

... and the second to parton distribution function (pdf) sets. The leading order Feynman diagrams for tW production are shown in ...1. The definition of tW production ... See full document

... Candidate events are selected in the dilepton topol- ...arise from leptonic τ decays and are included in the signal MC ...samples. The full object and event ... See full document

... signature of a charmed particle decay among the constituents of the leading jet associated with the W boson, as introduced in Section ...purpose, events with ... See full document

... results of a search for resonances in the t¯ t mass spectrum in a ...with the ATLAS detector during the 2011 proton-proton runs of the Large Hadron ... See full document

... those in Fig. 2, are excluded from the signal definition; and ‘‘diagram subtraction’’ (DS) [3,13], in which the differential cross section is modified with a gauge-invariant subtraction ... See full document

... F. Bachmair, L. B¨ani, L. Bianchini, P. Bortignon, M.A. Buchmann, B. Casal, N. Chanon, A. Deisher, G. Dissertori, M. Dittmar, M. Doneg`a, M. D ¨unser, P. Eller, K. Freudenreich, C. Grab, D. Hits, P. Lecomte, W. ... See full document

... for top-quark pairs (t¯ t) produced together with a photon (γ) with trans- verse energy greater than 20 GeV using a sample of t¯ t candidate events in final ... See full document

... A measurement of the tt production cross section in the channel tt → (` ν ` )( τν τ ) bb is presented, where ` is an electron or a muon, and the τ lepton is ... See full document

... tt events contain jets from the hadronization of b quarks, requiring b tagging can re- duce background from events that do not contains b ...jets. Jets are ... See full document

... set of 1000 pseudo-experiments was performed using the baseline simulation sample as a reference, and the mean and RMS width of the deviations of the result in each ... See full document

... to W+jets events in which a b quark, a charm quark, or a light quark is produced in association with the W ...boson. The overall ... See full document

... P.M. Tuts 38 , G. Ucchielli 22a,22b , I. Ueda 69 , M. Ughetto 148a,148b , F. Ukegawa 164 , G. Unal 32 , A. Undrus 27 , G. Unel 166 , F.C. Ungaro 91 , Y. Unno 69 , K. Uno 157 , C. Unverdorben 102 , J. Urban 146b , P. ... See full document

... with the higher instantaneous luminosities in the latter stages of the data taking period, requires an additional sixth jet with p T > 30 ...beyond the initial 3.54 fb ... See full document

... distributions of the W+jets back- ground, which comprises contributions from W+heavy flavour jets (Wb ¯b+jets, Wc¯c+jets and Wc+jets) and ... See full document

... b-quark production are available, depend- ing on whether there are four or five quark flavors in the proton parton distribution functions (PDFs) ...experimental measurement ... See full document

... determination of the top-quark mass sets a fundamental benchmark for the standard model (SM), and is one of the precision measurements that defines electroweak constraints ... See full document

... by the ATLAS [ 3 – 7 ] and CMS [ 8 – 11 ] Collaborations. The high centre-of-mass proton–proton (pp) collision energy of 13 TeV at the LHC, together with ... See full document

... correctly from simulation in the tt phase-space region. The contribution from the multijet background is estimated using an independent data control sample where the ... See full document

... single top quark production. The second most important variable is the invariant mass of the reconstructed top quark, which dis- criminates processes with ... See full document