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Related papers: Top-Quark Forward-Backward Symmetry

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The top forward-backward asymmetry (FBA) observed at the Tevatron has been a hot issue in particle physics for the last few years. In this talk, I describe two different approaches for the top FBA at the Tevatron, one in effective field…

High Energy Physics - Phenomenology · Physics 2013-01-09 P. Ko

We consider, at order $\alpha_s^2$ in the QCD coupling, top-quark pair production in the continuum at various center-of-mass energies and $b$-quark pair production at the $Z$ resonance by (un)polarized electron and positron beams. For top…

High Energy Physics - Phenomenology · Physics 2023-05-22 Werner Bernreuther , Long Chen , Peng-Cheng Lu , Zong-Guo Si

The CDF and D0 collaborations have recently reported a large forward-backward asymmetry in the ttbar system which deviates from the next to-leading order QCD standard model prediction. We study the asymmetry in the ttbar system within the…

High Energy Physics - Phenomenology · Physics 2015-06-03 Alejandro de la Puente

The measured forward-backward asymmetry in the t tbar production at the Tevatron might be explained by the additional exchange of a colored weak singlet scalar. Such state appears in some of the grand unified theories and its interactions…

High Energy Physics - Phenomenology · Physics 2010-12-09 Ilja Dorsner , Svjetlana Fajfer , Jernej F. Kamenik , Nejc Kosnik

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

A sizeable difference in the differential production cross section of top and antitop quarks, respectively, is predicted for hadronically produced heavy quarks. It is of order $\alpha_s$ and arises from the interference between charge odd…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. H. Kühn , G. Rodrigo

In order to explain the Tevatron anomaly of the top quark forward-backward asymmetry $A_{FB}^t$ in the left-right twin Higgs model, we choose to give up the lightest neutral particle of $\hat{h}$ field as a stable dark matter candidate.…

High Energy Physics - Phenomenology · Physics 2013-05-30 Lei Wang , Lei Wu , Jin Min Yang

Recently it has been shown that measurement of charge asymmetry of top pair production at LHC excludes any flavor violating $Z'$ vector gauge boson that could explain Tevatron forward-backward asymmetry (FBA). We consider the general form…

High Energy Physics - Phenomenology · Physics 2015-03-20 Seyed Yaser Ayazi

We explore the possibility that the large $t\bar t$ forward-backward asymmetry measured by the CDF detector at Tevatron could be due to a universal effective axial-vector coupling of gluon. Using an effective field theory approach we show…

High Energy Physics - Phenomenology · Physics 2013-05-29 Emidio Gabrielli , Martti Raidal

We analyze various models for the top quark forward-backward asymmetry ($A^t_{FB}$) at the Tevatron, using the latest CDF measurements on different $A^t_{FB}$s and the total cross section. The axigluon model in Ref. \cite{paul} has…

High Energy Physics - Phenomenology · Physics 2015-05-27 Jing Shu , Kai Wang , Guohuai Zhu

Recent measurements of the top quark forward-backward asymmetry at the Tevatron could hint at new physics with an unexpected flavor structure. The significance of such an abnormal flavor structure in alleviating the tension between the…

High Energy Physics - Phenomenology · Physics 2015-05-30 John N. Ng , Peter T. Winslow

The production of top-antitop pairs at the Fermilab Tevatron shows a forward-backward asymmetry in which the top quark tends to follow the proton direction, while the antitop tends to follow the antiproton direction. The effect grows with…

High Energy Physics - Phenomenology · Physics 2013-05-30 Jonathan L. Rosner

The forward-backward asymmetry of $b$-quark jets on the $Z$-pole measured at LEP/SLD experiments shows us -2.8-$\sigma$ deviation from the Standard Model (SM) prediction. We examine a possibility of Kaluza-Klein (KK) gluon to explain the…

High Energy Physics - Phenomenology · Physics 2014-11-18 Gi-Chol Cho , Yoshimi Kanehata

Heavy flavour production at hadron colliders represents a very promising field to test perturbative QCD. The integrated forward-backward asymmetry of the top-antitop quark production is particularly sensitive to any deviation from the…

General Physics · Physics 2013-04-12 Davor Palle

The anomaly of the top quark forward-backward asymmetry $A^t_{FB}$ observed at the Tevatron can be explained by the t-channel exchange of a neutral gauge boson (Z') which has sizable flavor changing coupling for top and up quarks. This…

High Energy Physics - Phenomenology · Physics 2013-05-29 Junjie Cao , Lin Wang , Lei Wu , Jin Min Yang

The CDF and D0 experiments at the Fermilab Tevatron have measured the asymmetry between yields of forward- and backward-produced top and antitop quarks based on their rapidity difference and the asymmetry between their decay leptons. These…

High Energy Physics - Experiment · Physics 2018-01-31 CDF collaboration , D0 collaboration

Motivated by the persistence of a large measured top quark forward-backward asymmetry at the Tevatron, we examine a model of non-Abelian flavor gauge symmetry. The exchange of the gauge bosons in the $t$-channel can give a large asymmetry…

High Energy Physics - Phenomenology · Physics 2011-07-05 Sunghoon Jung , Aaron Pierce , James D. Wells

The top quark forward-backward asymmetry measured at the Fermilab Tevatron collider deviates from the standard model prediction. A W^prime boson model is described, where the coupling W^prime-t-d is fixed by the tt_bar forward-backward…

High Energy Physics - Phenomenology · Physics 2015-06-04 Daniel Duffty , Zack Sullivan , Hao Zhang

The leading-order accurate description of top quark pair production, as usually employed in standard Monte Carlo event generators, gives no rise to the generation of a forward--backward asymmetry. Yet, non-negligible -- differential as well…

High Energy Physics - Phenomenology · Physics 2015-06-15 Jan Winter , Peter Z. Skands , Bryan R. Webber

We show that the forward-backward asymmetry in top quark pair production can be enhanced by fields that transform nontrivially under the flavour group and satisfy Minimal Flavour Violation, while at the same time the constraints from…

High Energy Physics - Phenomenology · Physics 2012-06-26 Benjamin Grinstein , Alexander L. Kagan , Michael Trott , Jure Zupan