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Related papers: Explaining the t-tbar asymmetry with a light axigl…

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The measurement of forward-backward asymmetry in the top and anti-top quark ($t \bar{t}$) production has been recently reconfirmed by the CDF Collaboration and shows a more than $3\sigma$ deviation from the Standard Model(SM) prediction in…

High Energy Physics - Phenomenology · Physics 2011-05-13 Biplob Bhattacherjee , Sudhansu S. Biswal , Diptimoy Ghosh

We adopt a Markov Chain Monte Carlo method to examine various new physics models which can generate the forward-backward asymmetry in top quark pair production observed at the Tevatron by the CDF Collaboration. We study the following new…

High Energy Physics - Phenomenology · Physics 2014-11-20 Qing-Hong Cao , David McKeen , Jonathan L. Rosner , Gabe Shaughnessy , Carlos E. M. Wagner

The top quark forward-backward asymmetry measured at the Tevatron collider shows a large deviation from standard model expectations. Among possible interpretations, a non-universal $Z^\prime$ model is of particular interest as it naturally…

High Energy Physics - Phenomenology · Physics 2011-05-23 Edmond L. Berger , Qing-Hong Cao , Chuan-Ren Chen , Chong Sheng Li , Hao Zhang

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

We use a recent upper limit from CDF on like-sign top pair production to place constraints on general new vector bosons and scalars mediating u u -> t t. The possible vector bosons comprise neutral colour singlets or octets, and charge 4/3…

High Energy Physics - Phenomenology · Physics 2011-06-28 J. A. Aguilar-Saavedra , M. Perez-Victoria

We suggest a new possibility for ATLAS and CMS to explore the t-tbar forward-backward asymmetry measured at the Tevatron, by attempting to reconstruct t-tbar events, with one of the tops decaying semileptonically in the central region…

High Energy Physics - Phenomenology · Physics 2011-12-06 Jean-François Arguin , Marat Freytsis , Zoltan Ligeti

The experimental results on the t bar t production cross section at the Tevatron are well described by the QCD contributions within the standard model, while the recent measurement of the forward-backward asymmetry cannot be accounted for…

High Energy Physics - Phenomenology · Physics 2010-06-18 Ilja Dorsner , Svjetlana Fajfer , Jernej F. Kamenik , Nejc Kosnik

Recent measurements of the top quark charge asymmetry at Tevatron disfavor the existence of flavor universal axigluons and colorons at 2 sigmas. In this letter we explore the possibility to reconcile the data with these models and use the…

High Energy Physics - Phenomenology · Physics 2009-10-20 Paola Ferrario , German Rodrigo

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

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

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

In this paper, forward-backward asymmetry and differential cross section of top quark in flavor violating $Z'$ model up to $\mathscr{O}(\alpha_s^2 \alpha_X)$ at Tevatron are calculated. In order to account for the top observed large…

High Energy Physics - Phenomenology · Physics 2010-09-21 Bo Xiao , You-kai Wang , Shou-hua Zhu

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

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

Flavor-violating interactions involving new heavy particles are among proposed explanations for the $t\bar t$ forward-backward asymmetry observed at the Tevatron. Many of these models generate a $t\bar t$-plus-jet signal at the LHC. In this…

High Energy Physics - Phenomenology · Physics 2013-05-30 Simon Knapen , Yue Zhao , Matthew J. Strassler

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 consider a model that includes light colored scalars from the {\bf 45} and {\bf 50} representations of SU(5) in order to explain the CDF- and D$\O$-reported $t\bar{t}$ forward-backward asymmetry, $A^{t\bar{t}}_{FB}$. These light scalars…

High Energy Physics - Phenomenology · Physics 2012-01-26 David C. Stone , Patipan Uttayarat

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 study different profiles of the distribution of the top forward-backward asymmetry, depending on the invariant mass of the t tbar pair. We show that they can be reproduced by one or more light colour octets, while keeping moderate…

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

Recent results from the CDF Collaboration indicate the the top-pair forward-backward asymmetry is largest in regions of high rapidity difference $|\Delta y|$ and invariant mass $M_{t\bar t}.$ We show that experimental observations can be…

High Energy Physics - Phenomenology · Physics 2011-03-28 Vernon Barger , Wai-Yee Keung , Chiu-Tien Yu