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

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We review the asymmetries in top quark pair production at the Tevatron and the LHC. We summarize the experimental measurements and the interpretations of a possible excess in terms of new physics. We also review other top quark…

High Energy Physics - Phenomenology · Physics 2015-06-11 J. A. Aguilar-Saavedra , D. Amidei , A. Juste , M. Perez-Victoria

Extensions of the Standard Model often predict new chiral interactions for top quark, which will contribute to top quark spin correlation and polarization in $t\bar{t}$ production at the LHC. In this work, under the constraints from the…

High Energy Physics - Phenomenology · Physics 2015-03-17 Junjie Cao , Lei Wu , Jin Min Yang

We review the most popular models proposed to explain the anomalous forward-backward asymmetry in t tbar production at the Tevatron. We discuss their viability in view of recent LHC data. We summarise their predictions for charge…

High Energy Physics - Phenomenology · Physics 2022-03-02 J. A. Aguilar-Saavedra

As a top quark factory, the LHC can test the new physics models used to explain the top quark forward-backward asymmetry A^t_FB measured at the Tevatron. In this work we perform a comparative study for two such models: the W'-model and the…

High Energy Physics - Phenomenology · Physics 2015-05-30 Junjie Cao , Ken-ichi Hikasa , Lin Wang , Lei Wu , Jin Min Yang

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 examine the implications of the recent CDF measurement of the top-quark forward-backward asymmetry, focusing on a scenario with a new color octet vector boson at 1-3 TeV. We study several models, as well as a general effective field…

High Energy Physics - Phenomenology · Physics 2015-03-18 Yang Bai , JoAnne L. Hewett , Jared Kaplan , Thomas G. Rizzo

If the forward-backward (FB) asymmetry of top quark ($A_{\rm FB}$) observed at the Tevatron deviates from the SM prediction, there must be $P$-violating interactions in $q\bar{q} \rightarrow t\bar{t}$. This new interaction will necessarily…

High Energy Physics - Phenomenology · Physics 2011-08-19 Dong-Won Jung , P. Ko , Jae Sik Lee

We consider new physics explanations of the anomaly in the top quark forward-backward asymmetry measured at the Tevatron, in the context of flavor conserving models. The recently measured LHC dijet distributions strongly constrain many…

High Energy Physics - Phenomenology · Physics 2015-05-27 Zoltan Ligeti , Gustavo Marques Tavares , Martin Schmaltz

The forward-backward asymmetry for top quarks measured in proton-antiproton collisions at the Tevatron shows an interesting deviation from standard model expectations. Among possible interpretations, the exchange of a non-universal,…

High Energy Physics - Phenomenology · Physics 2011-09-16 Edmond L. Berger

The measurement of a charge asymmetry in t tbar production at LHC constitutes more than an independent confirmation of the forward-backward asymmetry found at Tevatron. Indeed, both measurements together can be used to identify the source…

High Energy Physics - Phenomenology · Physics 2015-05-28 J. A. Aguilar-Saavedra , M. Perez-Victoria

The dijet signature at the LHC is studied in new physics models for the top forward-backward asymmetry at the Tevatron. In the t-mediator models, flavor-changing interactions contribute to the dijet production cross section as well as the…

High Energy Physics - Phenomenology · Physics 2011-10-04 Motoi Endo , Sho Iwamoto

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

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

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

This talk reviews the Standard Model predictions for the top-quark forward backward and charge asymmetries measured at the Tevatron and at the LHC.

High Energy Physics - Phenomenology · Physics 2012-12-27 Valentin Ahrens , Andrea Ferroglia , Matthias Neubert , Benjamin Pecjak , Lilin Yang

The latest measurements of the asymmetry in the angular distributions of the $t\bar{t}$ events are reviewed. The measurements of the forward-backward asymmetry $A_{FB}$ in the $p\bar{p}$ 1.98 TeV collision at the Tevatron show some tension…

High Energy Physics - Experiment · Physics 2013-12-03 Viatcheslav Sharyy

A sizable charge asymmetry in top quark pair production has been observed at the Tevatron. The experimental results seem to exceed systematically the Standard Model theory predictions by a significant amount and have triggered a large…

High Energy Physics - Phenomenology · Physics 2012-07-03 German Rodrigo

We carry out a comprehensive analysis of models for top A_{FB} at CDF in light of new top data arriving from the LHC. We begin with a careful Tevatron analysis, considering in general which sets of effective vertices give rise to a large…

High Energy Physics - Phenomenology · Physics 2015-03-19 Moira I. Gresham , Ian-Woo Kim , Kathryn M. Zurek

Both D0 and CDF at Tevatron reported the measurements of forward-backward asymmetry in top pair production, which showed possible deviation from the standard model QCD prediction. In this paper, we explore how to examine the {\em same}…

High Energy Physics - Phenomenology · Physics 2011-02-01 You-kai Wang , Bo Xiao , Shou-hua Zhu

The latest CDF and D0 experiment measurements of the top quark properties except the top quark mass are presented. The final combination of the CDF and D0 forward-backward asymmetry measurements is shown together with the D0 measurements of…

High Energy Physics - Experiment · Physics 2017-11-28 Roman Lysák