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Related papers: Top polarization, forward-backward asymmetry and n…

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We present the most recent CDF results in the measurements of the decay and production vertex of the top-quark. New results on forward-backward asymmetry in top-antitop events are presented. Also, recent measurements of the branching…

High Energy Physics - Experiment · Physics 2015-06-23 Giorgio Chiarelli

The heaviest known elementary particle today, the top quark, has been discovered in 1995 by the CDF and D0 collaborations at the Tevatron proton antiproton collider at Fermilab. Recently, the CDF and D0 collaborations have studied the…

High Energy Physics - Experiment · Physics 2019-08-15 Yvonne Peters

Transverse polarization (TP) can be used to study interference of (S,P) or T type couplings from new physics with the SM contribution. In e+e- -> t tbar, a CP-odd azimuthal asymmetry can constrain the scale Lambda of new (S,P) or T contact…

High Energy Physics - Phenomenology · Physics 2007-05-23 Saurabh D. Rindani

New colour octet vectors below the TeV scale could explain the anomalous t tbar forward-backward asymmetry observed at the Tevatron experiments, while being consistent with the current LHC data. These models generally lead to four-top final…

High Energy Physics - Phenomenology · Physics 2015-06-03 J. A. Aguilar-Saavedra , Jose Santiago

We use an effective operator framework to study the contributions to the Tevatron t tbar asymmetry from arbitrary vector bosons and scalars, and compare with their effect on the t tbar tail at LHC. Our study shows, for example, that models…

High Energy Physics - Phenomenology · Physics 2011-07-14 J. A. Aguilar-Saavedra , M. Perez-Victoria

Models of top condensation can provide both a compelling solution to the hierarchy problem as well as an explanation of why the top-quark mass is large. The spectrum of such models, in particular topcolor-assisted technicolor, includes…

High Energy Physics - Phenomenology · Physics 2015-05-28 Yanou Cui , Zhenyu Han , Matthew D. Schwartz

We investigate the prospects to observe effects of transverse polarization of top quarks in $pp,p\bar{p}\to t\bar{t}X$. QCD absorptive parts generate a polarization of top quarks and antiquarks transverse to the production plane in the…

High Energy Physics - Phenomenology · Physics 2009-10-28 Werner Bernreuther , Arnd Brandenburg , Peter Uwer

We provide the most up-to-date predictions for the top-quark charge asymmetry A_C at the LHC with a centre-of-mass energy of 8 TeV. Our result is accurate at the NNLO level in the strong interactions and at the complete-NLO level in both…

High Energy Physics - Phenomenology · Physics 2018-07-11 Michal Czakon , David Heymes , Alexander Mitov , Davide Pagani , Ioannis Tsinikos , Marco Zaro

The forward-backward asymmetry $A_{FB}$ in top quark pair production, measured at the Tevatron, is probably related to the contribution of new particles. The Tevatron result is more than a $2\sigma$ deviation from the standard model…

High Energy Physics - Phenomenology · Physics 2011-03-21 E. Ramirez Barreto , Y. A. Coutinho , J. Sá Borges

The CDF and D0 experiments have reported on the measurement of the forward-backward asymmetry of top quark pair production at the Tevatron and the result is that it is more than 2 standard deviations above the predicted value in the…

High Energy Physics - Phenomenology · Physics 2011-05-24 Abdelhak Djouadi , Gregory Moreau , Francois Richard , Ritesh K. Singh

We propose a charged, electrically neutral, and flavour changing Z' model to conciliate the apparent disagreement between the important excess found in the top-antitop Tevatron forward-backward asymmetry and the null -compatible with…

High Energy Physics - Phenomenology · Physics 2013-05-30 Ezequiel Alvarez , Estefania Coluccio Leskow

The polarisation of top quarks produced in high energy processes can be a very sensitive probe of physics beyond the Standard Model. The kinematical distributions of the decay products of the top quark can provide clean information on the…

High Energy Physics - Phenomenology · Physics 2015-06-03 Rohini M. Godbole , Lisa Hartgring , Irene Niessen , Chris D. White

Top quarks may be produced in large numbers in association with new physics at the LHC. The polarization of these top quarks probes the chiral structure of the new physics. We discuss several kinematic distributions which are sensitive to…

High Energy Physics - Phenomenology · Physics 2009-02-18 Jessie Shelton

The existence of an exactly scale invariant sector possessing a non-trivial infrared fixed point at a higher energy scale and its possible communication with the Standard Model particles through a heavy messenger sector has been shown to…

High Energy Physics - Phenomenology · Physics 2008-11-26 Debajyoti Choudhury , Dilip Kumar Ghosh

The top quark is the most recently discovered of the standard model quarks, and studies of its properties are important tests of the standard model. Many measurements of top properties have been produced by the CDF and D0 collaborations,…

High Energy Physics - Experiment · Physics 2019-08-14 David J. Mietlicki

We study the sensitivity of the Large Hadron Collider (LHC) to anomalous tbW couplings in single-top production in association with a W^- boson followed by semileptonic decay of the top. We calculate top polarization and the effects of…

High Energy Physics - Phenomenology · Physics 2015-05-28 Saurabh D. Rindani , Pankaj Sharma

I review the prospects for measuring the properties of the top quark at the Tevatron, with an integrated luminosity of 2 fb$^{-1}$ or more, and at LHC in the early running at instantaneous luminosities of $10^{32}-10^{33}~cm^{-2}~s^{-1}$.

High Energy Physics - Phenomenology · Physics 2007-05-23 Tony M. Liss

The electroweak contributions to the forward-backward asymmetry in the production of top-quark pairs at the Tevatron are evaluated at O(alpha^2) and O(alpha*alphas^2). We perform a detailed analysis of all partonic channels that produce an…

High Energy Physics - Phenomenology · Physics 2013-05-29 Wolfgang Hollik , Davide Pagani

The lepton or baryon number violating top quark interactions in the supersymmetric standard model with R parity violation contribute to the process d dbar to t tbar at the tree level via the t- or u-channel sfermion exchange. Since these…

High Energy Physics - Phenomenology · Physics 2009-10-31 Ken-ichi Hikasa , Jin Min Yang , Bing-Lin Young

The Standard Model of particle physics has a number of asymmetries suggestive of a more fundamental theory, where the symmetries are restored. If the symmetry breaking scale is the electroweak scale, new Higgs bosons beyond that of the…

High Energy Physics - Experiment · Physics 2019-08-14 Chris Hays