English
Related papers

Related papers: Longitudinal top polarisation measurement and anom…

200 papers

Top spin correlation has been shown to be nontrivial in hadronic top-pair production, and can be realized by the asymmetries of the decay products of the top quark and antiquark. We show in this work that the top spin correlation is a…

High Energy Physics - Phenomenology · Physics 2015-06-25 Kingman Cheung

To probe the $Wtb$ vertex structure, top-quark and $W$-boson polarisation observables are measured from $t$-channel single-top-quark events produced in proton--proton collisions at a centre-of-mass energy of 8 TeV. The dataset corresponds…

High Energy Physics - Experiment · Physics 2017-08-25 ATLAS Collaboration

We investigate a number of observables that are and will be instrumental in the exploration of $\tbart$ production and decay at the Tevatron and the LHC. For this analysis we made a computer program that incorporates besides the NLO QCD…

High Energy Physics - Phenomenology · Physics 2014-11-20 Werner Bernreuther , Zong-Guo Si

Measurements of distributions associated with the pair production of top quarks at the LHC can be used to constrain (or observe) the anomalous chromomagnetic dipole moment($\kappa$) of the top. For example, using either the $t\bar t$…

High Energy Physics - Phenomenology · Physics 2011-03-02 Thomas G. Rizzo

The polarization of a top-quark can be sensitive to new physics beyond the standard model. We propose a novel method to measure top-quark polarization, based on the charged lepton energy fraction in top-quark decay, and illustrate the…

High Energy Physics - Phenomenology · Physics 2013-06-03 Edmond L. Berger , Qing-Hong Cao , Jiang-Hao Yu , Hao Zhang

We introduce a new asymmetry in the decay t -> W b -> l nu b, which is shown to be directly proportional to the polarisation of the top quark along a chosen axis, times a sum of W helicity fractions. The latter have already been precisely…

High Energy Physics - Phenomenology · Physics 2015-06-11 J. A. Aguilar-Saavedra , R. V. Herrero-Hahn

We study the accuracy with which the lowest order $CP$ conserving anomalous $Wtb$ couplings in the single top quark production at the proposed large hadron electron collider (LHeC) can be probed. The one dimensional distribution of various…

High Energy Physics - Phenomenology · Physics 2015-10-27 Sukanta Dutta , Ashok Goyal , Mukesh Kumar , Bruce Mellado

Stringent tests on top quark production and decay mechanisms are provided by the measurement of the top quark and W boson polarization. This paper presents a detailed study of these two measurements with the ATLAS detector, in the…

High Energy Physics - Experiment · Physics 2014-11-17 F. Hubaut , E. Monnier , P. Pralavorio , V. Simak , K. Smolek

Anomalous Wtb couplings modify the angular correlations of the top quark decay products and change the single top quark production cross section. We present limits on anomalous top quark couplings by combining information from W boson…

High Energy Physics - Experiment · Physics 2009-04-08 D0 Collaboration , V. Abazov

Angular distributions of a mu+ and a b-quark resulting from the decay of a top quark produced at the e+e- linear collider with an unpolarized and a 100% longitudinally polarized electron beam are presented. The results of the standard model…

High Energy Physics - Phenomenology · Physics 2007-05-23 K. Cieckiewicz , K. Kolodziej

We consider top-antitop quark $(t{\bar t})$ production at the Large Hadron Collider (LHC) with subsequent decays into dileptonic final states. We use and investigate a set of leptonic angular correlations and distributions with which all…

High Energy Physics - Phenomenology · Physics 2024-05-30 Werner Bernreuther , Long Chen , Zong-Guo Si

Precise measurements of the properties of the top quark test the Standard Model (SM) and can be used to constrain new physics models. The top quark pair charge asymmetry is an asymmetry predicted to occur beyond leading-order QCD in the SM,…

High Energy Physics - Experiment · Physics 2016-07-08 Mohammad J. Kareem

The search for new physics in top quark decays at the LHC is reviewed in this paper. Results from ATLAS and CMS experiments on top quark decays within the Standard Model are presented together with the measurements of the W boson…

High Energy Physics - Experiment · Physics 2013-01-01 A. Onofre

Polarization observables in top quark decays are sensitive probes of possible new physics contributions to the interactions of the heavy third generation quarks. Within an effective theory approach such new physics contributions can be…

High Energy Physics - Phenomenology · Physics 2011-05-20 Jernej F. Kamenik

Angular-energy distributions are studied for charged leptons and neutrinos from the decays of polarised top quarks. A small admixture of V+A interactions is incorporated. The polarisation dependent part of the neutrino distribution which…

High Energy Physics - Phenomenology · Physics 2009-10-28 M. Jeżabek , J. H. Kühn

We consider the decay of a polarized top quark into a polarized W-boson plus a bottom quark, followed by the decay of the W-boson into a pair of leptons or quarks. The polar angle distribution of the top spin relative to the W-momentum and…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. Fischer , S. Groote , J. G. Körner , M. C. Mauser , B. Lampe

We present a quantitative study on sensitivities to the top-decay anomalous couplings, taking into account realistic experimental conditions expected at Tevatron and LHC. A double angular distribution of W and charged lepton in the top…

High Energy Physics - Experiment · Physics 2009-11-11 S. Tsuno , I. Nakano , Y. Sumino , R. Tanaka

The electroweak production and subsequent decay of single top quarks in the $t$-channel is determined by the properties of the $Wtb$ vertex, which can be described by the complex parameters of an effective Lagrangian. An analysis of a…

High Energy Physics - Experiment · Physics 2017-12-18 ATLAS Collaboration

We investigate the possibility that an imaginary anomalous $tbW$ coupling can be measured in the process $pp \to tW^-X$ by means of T-odd observables. One such observable is the polarization of the top quark transverse to the production…

High Energy Physics - Phenomenology · Physics 2025-01-28 Saurabh D. Rindani

The $Wtb$ vertex structure and the search for new anomalous couplings is studied using top quark measurements obtained at the LHC, for a centre-of-mass energy of 8 TeV. By combining the latest and most precise results on the single top…

High Energy Physics - Phenomenology · Physics 2014-12-17 César Bernardo , N. F. Castro , Miguel C. N. Fiolhais , Hugo Gonçalves , André G. C. Guerra , Miguel Oliveira , A. Onofre