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Related papers: Top-Quark Asymmetry -- A New Physics Overview

200 papers

The measured forward-backward asymmetry in top pair events at the Fermilab Tevatron collider deviates significantly from the standard model expectation. Several models have been proposed to describe the observed asymmetry which grows with…

High Energy Physics - Phenomenology · Physics 2012-10-25 Seyed Yaser Ayazi , Sara Khatibi , Mojtaba Mohammadi Najafabadi

At the LHC, top quark pairs are dominantly produced from gluons, making it difficult to measure the top quark forward-backward asymmetry. To improve the asymmetry measurement, we study variables that can distinguish between top quarks…

High Energy Physics - Phenomenology · Physics 2015-05-28 Yang Bai , Zhenyu Han

I review the current status of the charge asymmetry in hadronic top-quark pair production from a theory perspective. The standard-model predictions for the observables at the Tevatron and LHC are being discussed, as well as possible…

High Energy Physics - Phenomenology · Physics 2013-11-06 Susanne Westhoff

We compute, for top quark pair production at the Tevatron and the Large Hadron Collider, the collider-independent forward-backward asymmetries defined in [1] in the standard model at next-to-leading order in QCD, including also…

High Energy Physics - Phenomenology · Physics 2013-05-30 J. A. Aguilar-Saavedra , W. Bernreuther , Z. -G. Si

We provide a qualitative and quantitative unified picture of the charge asymmetry in top quark pair production at hadron colliders in the SM and summarise the most recent experimental measurements.

High Energy Physics - Phenomenology · Physics 2014-11-19 Johann H. Kuehn , German Rodrigo

We propose two new observables to measure the charge asymmetry in hadronic top-quark pair production in association with a hard jet. The incline asymmetry, based on the inclination between the planes of initial- and final-state momenta,…

High Energy Physics - Phenomenology · Physics 2013-09-27 Stefan Berge , Susanne Westhoff

We revisit the possibility that the top quark forward-backward asymmetry arises from the on-shell production and decay of scalar top partners to top-antitop pairs with missing transverse energy. Although the asymmetry is produced by…

High Energy Physics - Phenomenology · Physics 2013-11-22 Abhishek Kumar , John N. Ng , Andrew Spray , Peter T. Winslow

The discovery of the top quark in 1995 opened a whole new sector of investigation of the Standard Model; today top quark physics remains a key priority of the Tevatron program. Some of the measurements of top quark properties, for example…

High Energy Physics - Experiment · Physics 2015-03-19 Fabrizio Margaroli

The top quark forward-backward asymmetry A_{FB}^t measured at the Tevatron is above the Standard Model prediction by more than 2-sigma deviation, which might be a harbinger for new physics. In this work we examine the contribution to…

High Energy Physics - Phenomenology · Physics 2010-04-06 Junjie Cao , Zhaoxia Heng , Lei Wu , Jin Min Yang

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

The top quark is the heaviest elementary particle observed to date. Its large mass makes the top quark an ideal laboratory to test predictions of perturbation theory concerning heavy quark production at hadron colliders. The top quark is…

High Energy Physics - Phenomenology · Physics 2009-11-11 Wolfgang Wagner

A sizeable difference in the differential production cross section of top- compared to antitop-quark production, denoted charge asymmetry, has been observed at the Tevatron. The experimental results seem to exceed the theory predictions…

High Energy Physics - Phenomenology · Physics 2015-05-30 Johann H. Kuhn , German Rodrigo

Forward-backward asymmetries $A_{FB}^t$ and $A_{FB}^\ell$ are observed in the top quark $t$ rapidity distribution and in the rapidity distribution of charged leptons $\ell$ from top quark decay at the Tevatron proton-antiproton collider,…

High Energy Physics - Phenomenology · Physics 2013-01-23 Edmond L. Berger

The latest results on top quark physics, namely single top quark production cross sections, $W$-boson helicity and asymmetry measurements are used to probe the Lorentz structure of the $Wtb$ vertex. The increase of sensitivity to new…

The study of top quark asymmetries at the LHC provides an excellent opportunity to probe subtle differences in the production of top quarks and antiquarks made by the standard model of particle physics. In this contribution, the latest…

High Energy Physics - Experiment · Physics 2026-04-17 Nils Faltermann

Both CDF and DO report a forward-backward asymmetry in t-tbar production that is above the standard model prediction. We review new physics models that can give a large forward backward asymmetry in t-tbar production at the Tevatron and the…

High Energy Physics - Phenomenology · Physics 2012-10-22 Jernej F. Kamenik , Jing Shu , Jure Zupan

The charge asymmetry in hadronic top-antitop-quark production is a powerful test observable of perturbative quantum chromodynamics. Since its origin in terms of Feynman diagrams is distinct from charge-symmetric top-antitop production,…

High Energy Physics - Phenomenology · Physics 2015-01-30 Susanne Westhoff

With the full Tevatron Run II and early LHC data samples, the opportunity for furthering our understanding of the properties of the top quark has never been more promising. Although the current knowledge of the top quark comes largely from…

High Energy Physics - Experiment · Physics 2015-06-03 Kevin Lannon , Fabrizio Margaroli , Chris Neu

The recent Tevatron measurement of the forward-backward asymmetry of the top quark shows an intriguing discrepancy with Standard Model expectations, particularly at large $\ttbar$ invariant masses. Measurements of this quantity are subtle…

High Energy Physics - Phenomenology · Physics 2013-05-29 JoAnne L. Hewett , Jessie Shelton , Michael Spannowsky , Tim M. P. Tait , Michihisa Takeuchi

Among different measured observables of top-antitop quark pairs at hadron colliders, the forward-backward asymmetry ($A_{\text{FB}}$) measured by the CDF and D0 collaborations has inconsistency with the Standard Model prediction. The…

High Energy Physics - Phenomenology · Physics 2013-02-21 Sara Khatibi , Mojtaba Mohammadi Najafabadi