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Related papers: A New Decoupling Theorem in Top-Quark Physics

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The polarization of a top quark can be sensitive to new physics beyond the standard model. Since the charged lepton from top quark decay is maximally correlated with the top quark spin, it is common to measure the polarization from the…

High Energy Physics - Phenomenology · Physics 2013-05-30 Edmond L. Berger , Qing-Hong Cao , Jiang-Hao Yu , Hao Zhang

An optimal-observable analysis of the lepton angular and energy distributions from top-quark pair production with semi-leptonic decays in e+e- collisions is used to predict the potential sensitivity of the FCC-ee to the couplings of the top…

High Energy Physics - Phenomenology · Physics 2015-06-11 Patrick Janot

An optimal-observable analysis of the angular and energy distributions of the leptons and bottom quarks in the process e+e- --> tt-bar --> l^{+-}/b(b-bar)... has been performed in order to measure the most general top-quark couplings to…

High Energy Physics - Phenomenology · Physics 2015-03-19 Bohdan Grzadkowski , Zenro Hioki

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

We review some recent theoretical progresses towards the determination of the top-quark couplings beyond the standard model. We briefly introduce the global effective field theory approach to the top-quark production and decay processes,…

High Energy Physics - Phenomenology · Physics 2017-08-31 Cen Zhang

In ongoing and upcoming hadron collider experiments, top quark physics will play an important role in testing the Standard Model and its possible extensions. In this work we present analytic results for the differential cross sections of…

High Energy Physics - Phenomenology · Physics 2011-05-05 W. Bernreuther , A. Brandenburg , Z. G. Si , P. Uwer

In the presence of an electric dipole coupling of t-tbar to a photon, and an analogous "weak" dipole coupling to the Z, CP violation in the process e+e- --> t tbar results in modified polarization of the top and anti-top. This polarization…

High Energy Physics - Phenomenology · Physics 2008-11-26 Saurabh D. Rindani

Direct and indirect information on the top quark mass and its decay modes is reviewed. The theory of top production in hadron- and electron-positron-colliders is presented.

High Energy Physics - Phenomenology · Physics 2009-09-25 J. H. Kuehn

We review the field of top-quark physics with an emphasis on experimental techniques. The role of the top quark in the Standard Model of particle physics is summarized and the basic phenomenology of top-quark production and decay is…

High Energy Physics - Experiment · Physics 2012-07-10 Frederic Deliot , Douglas Glenzinski

In the presence of an electric dipole coupling of the top quark to a photon, and an analogous "weak" dipole coupling to the Z, CP violation in the process e+e- -> t tbar leads to the polarization of the top and anti-top. This polarization…

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

In this paper we study new-physics contributions to the top-quark decay $t \to b \bar b c$. We search for ways of detecting such new physics via measurements at the LHC. As top quarks are mainly produced at the LHC in $t \bar t$ production…

High Energy Physics - Phenomenology · Physics 2015-10-02 Ken Kiers , Pratishruti Saha , Alejandro Szynkman , David London , Samuel Judge , Jordan Melendez

Kinematical distributions of decay products of the top quark carry information on the polarisation of the top as well as on any possible new physics in the decay of the top quark. We construct observables in the form of asymmetries in the…

High Energy Physics - Phenomenology · Physics 2015-08-17 Arun Prasath , Rohini M. Godbole , Saurabh D. Rindani

I demonstrate that the correlated angular distributions of final-state particles in both single-top-quark production and the dominant Wjj backgrounds can be reliably predicted. Using these fully-correlated angular distributions, I propose a…

High Energy Physics - Phenomenology · Physics 2008-11-26 Zack Sullivan

We show how to observe sizable angular correlations between the decay products of the top quark and those of the anti-top quark in top quark pair production and decay at hadron colliders. These correlations result from the large asymmetry…

High Energy Physics - Phenomenology · Physics 2014-11-17 Gregory Mahlon , Stephen Parke

We describe how to probe new physics through examination of the form factors describing the Ztt couplings via the scattering process e^-e^+->t+tbar. We focus on experimental methods on how the top quark momentum can be determined and show…

High Energy Physics - Phenomenology · Physics 2010-11-01 G. A. Ladinsky , C. -P. Yuan

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

Since the discovery of parity violation in 1957, angular distributions of leptons coming from the weak decay of polarized fermions have been used to probe the structure of the Wqq' vertex. Vector and axial vector couplings reveal themselves…

High Energy Physics - Experiment · Physics 2013-04-23 Joseph Boudreau , Carlos Escobar , James Mueller , Kevin Sapp , Jun Su

Recent calculations are presented of top quark polarization in $t\bar t$ pair production close to threshold. S-P-wave interference gives contributions to all components of the top quark polarization vector. Rescattering of the decay…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. Jezabek , R. Harlander , J. H. Kuehn , M. Peter

Quantum entanglement is a form of correlation between quantum particles that has now become a crucial part in quantum information and communication science. For example, it has been shown to enable or enhance quantum processing tasks such…

Quantum Physics · Physics 2020-03-20 Tanjung Krisnanda

In this talk we present the current status of the theoretical description of the production of top-quark pairs at the LHC, detailing recent progress for predictions at the stable-top level as well as for predictions that include the decay…

High Energy Physics - Phenomenology · Physics 2018-01-08 Andrew S. Papanastasiou