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The top quark was discovered in 1995. The top quark mass is now well measured at the Tevatron, with uncertainty getting below 1% of the top mass. The world average from last year was 170.9 $\pm$ 1.8 GeV/$c^2$. The new CDF measurement is 172…

High Energy Physics - Experiment · Physics 2008-05-16 Yen-Chu Chen

At hadron colliders, top quarks are dominantly produced in pairs ($t\bar{t}$), a production mechanism that was discovered more than twenty years ago at the Tevatron in Fermilab. Although the \ttbar process has already entered the domain of…

High Energy Physics - Experiment · Physics 2019-08-13 Juan R. González Fernández

We present a comprehensive study of differential distributions for Tevatron top-pair events at the level of stable top quarks. All calculations are performed in NNLO QCD with the help of a fully differential partonic Monte-Carlo and are…

High Energy Physics - Phenomenology · Physics 2016-05-25 Michal Czakon , Paul Fiedler , David Heymes , Alexander Mitov

We show that the charge asymmetry in t tbar production at the LHC, A_C, and the forward-backward asymmetry at the Tevatron, A_FB, are in general not tightly correlated. They can even have opposite signs, if the underlying new physics (NP)…

High Energy Physics - Phenomenology · Physics 2013-05-30 Jure Drobnak , Jernej F. Kamenik , Jure Zupan

In the $pp \rightarrow t\bar{t}$ process the angular distributions of top and anti-top quarks are expected to present a subtle difference, which could be enhanced by processes not included in the Standard Model. This Letter presents a…

High Energy Physics - Experiment · Physics 2016-11-21 ATLAS Collaboration

The anomalous forward-backward asymmetry (A_FB) in t tbar production at the Tevatron is in apparent contradiction with the t tbar charge asymmetry (A_C) measurements at the LHC, which agree well with the standard model predictions. We argue…

High Energy Physics - Phenomenology · Physics 2012-12-04 Jure Drobnak , Alexander L. Kagan , Jernej F. Kamenik , Gilad Perez , Jure Zupan

The measurement of the top quark pair production cross section in proton-antiproton collisions at 1.96 TeV is a test of quantum chromodynamics and could potentially be sensitive to new physics beyond the standard model. I report on the…

High Energy Physics - Experiment · Physics 2019-08-14 Jason Nielsen

First observed in 1995, the top quark is one of a pair of third-generation quarks in the Standard Model of particle physics. It has charge +2/3e and a mass of 171.4 GeV, about 40 times heavier than its partner, the bottom quark. The CDF and…

High Energy Physics - Experiment · Physics 2019-08-15 A. P. Heinson

Recent measurements of top-quark properties at the Tevatron, including top quark production asymmetries and properties, are presented. Latest updates of measurements of top quark production asymmetries include the measurement of the…

High Energy Physics - Experiment · Physics 2014-12-15 Andreas Werner Jung

Following the confirmation of the top quark discovery at the Tevatron, the next step is to begin studying its properties. Because the scale of electroweak symmetry breaking is of the same order as the measured top mass, the top quark may be…

High Energy Physics - Experiment · Physics 2007-05-23 Anthony Vaiciulis

The charge asymmetry in top quark pair production in the di-lepton $t\bar t$ channel using the ATLAS experiment at Large Hadron Collider is presented. The asymmetry is studied in the distribution of absolute rapidity difference between top…

High Energy Physics - Experiment · Physics 2012-12-04 Jakub Cúth

We define a lepton-based asymmetry in semi-leptonic ttbar production at the LHC. We show that the ratio of this lepton-based asymmetry and the ttbar charge asymmetry, measured as a function of the lepton transverse momentum or the ttbar…

High Energy Physics - Phenomenology · Physics 2015-06-18 Adrian Carmona , Mikael Chala , Adam Falkowski , Sara Khatibi , Mojtaba Mohammadi Najafabadi , Gilad Perez , Jose Santiago

It has been more than 15 years since the discovery of the top quark. Great strides have been made in the measurement of the top quark mass and the properties of it. Most results show consistency with the standard model. However, using 5…

High Energy Physics - Experiment · Physics 2019-08-14 Yen-Chu Chen

A technique for separating top quark production from Standard Model background events is introduced. It is applicable to the channel in which one top quark decays semi-leptonically and its anti-quark decays hadronically into three jets, or…

High Energy Physics - Phenomenology · Physics 2010-11-01 Gary R. Goldstein , K. Sliwa , R. H. Dalitz

We present a measurement of forward-backward asymmetry in top quark-antiquark production in proton-antiproton collisions in the final state containing a lepton and at least four jets. Using a dataset corresponding to an integrated…

High Energy Physics - Experiment · Physics 2012-08-27 D0 Collaboration

An extra $U(1)'$ model with $Z'$ coupled only to the right-handed (RH) up-type quarks has been one of the popular models for the Tevatron top forward-backward asymmetry (FBA), and has been excluded by the same-sign top-pair productions at…

High Energy Physics - Phenomenology · Physics 2015-06-15 P. Ko , Yuji Omura , Chaehyun Yu

We compute QCD corrections to the production of a ttbar pair in association with a hard photon at the Tevatron and the LHC. This process allows a direct measurement of the top quark electromagnetic couplings that, at the moment, are only…

High Energy Physics - Phenomenology · Physics 2015-03-18 Kirill Melnikov , Andreas Scharf , Markus Schulze

In this review article three promising aspects of top quark production are discussed: the charge asymmetry in top quark pair production, the search for resonant top quark pair production, and electroweak single top quark production. First,…

High Energy Physics - Experiment · Physics 2016-08-03 Jeannine Wagner-Kuhr

Fermilab's Tevatron accelerator is recently performing at record luminosities that enables a program systematically addressing the physics of top quarks. The CDF and D0 collaborations have analyzed up to 5/fb of proton anti-proton…

High Energy Physics - Experiment · Physics 2019-08-14 Bernd Stelzer

The top quark is the most recently discovered of the standard model quarks, and because of its very large mass, studies of the top quark and its interactions are important both as tests of the standard model and as searches for new physical…

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