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Related papers: A Revisit to Top Quark Forward-Backward Asymmetry

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We consider the recent measurement of the top quark forward-backward asymmetry at the Fermilab Tevatron, which shows a discrepancy of slightly more than 2$\sigma$ compared to the SM prediction. We find that $t$-channel exchange of a color…

High Energy Physics - Phenomenology · Physics 2010-12-09 Jing Shu , Tim M. P. Tait , Kai Wang

Aspects of a flavor-changing W' model with right-handed couplings are addressed in this paper in light of Tevatron and LHC data. Our fit to the Tevatron top-quark forward-backward asymmetry and the tt_bar inclusive cross section includes…

High Energy Physics - Phenomenology · Physics 2015-06-17 Edmond L. Berger , Zack Sullivan , Hao Zhang

Very recently, it has been shown by other authors that the CDF measurement of the top quark forward-backward asymmetry can be explained by means of a heavy and broad axigluon. In order to work, this mechanism needs that the axigluon…

High Energy Physics - Phenomenology · Physics 2015-05-27 Alfonso R. Zerwekh

In light of the recent measurements of the top quark forward-backward asymmetry at the Fermilab Tevatron experiment, which in some regions of the parameter space shows a discrepancy of 3$\sigma$ compared to the SM prediction, we analyze top…

High Energy Physics - Phenomenology · Physics 2013-05-29 Mariana Frank , Alper Hayreter , Ismail Turan

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

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

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

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 forward-backward asymmetry in top pair production at the Tevatron has long been in tension with the Standard Model prediction. One of the only viable new physics scenarios capable of explaining this anomaly is an s-channel axigluon-like…

High Energy Physics - Phenomenology · Physics 2015-06-15 Matthew Baumgart , Brock Tweedie

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

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

Recently the CDF and the D0 Collaborations presented the data on the top forward-backward (FB) asymmetry A_FB as functions of M_(t t^bar) and \Delta y = y_t - y_t^bar. We study these observables in the effective Lagrangian approach with…

High Energy Physics - Phenomenology · Physics 2015-06-03 Dong-Won Jung , P. Ko , Jae Sik Lee

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

We study an SU(3)^2 axigluon model introduced by Frampton, Shu, and Wang to explain the recent Fermilab Tevatron observation of a significant positive enhancement in the top quark forward-backward asymmetry relative to standard model…

High Energy Physics - Phenomenology · Physics 2010-12-13 R. Sekhar Chivukula , Elizabeth H. Simmons , C. -P. Yuan

We propose a simple model where dark matter (DM) carries top flavor and couples to the Standard Model through the top quark within a framework of minimal flavor violation (MFV). Top-flavored DM can explain the anomalous top forward-backward…

High Energy Physics - Phenomenology · Physics 2013-05-15 Abhishek Kumar , Sean Tulin

Motivated by a possible anomaly in the forward-backward (FB) asymmetry of top quark (A_{\rm FB}) observed at the Tevatron, we perform a model independent analysis on q \bar{q} \to t \bar{t} using an effective lagrangian with dim-6…

High Energy Physics - Phenomenology · Physics 2014-11-20 Dong-Won Jung , P. Ko , Jae Sik Lee , Soo-hyeon Nam

We show that the scalar sector needed for fermion mass generation when the flavor symmetry of the standard model is maximally gauged can consistently explain two anomalies reported recently by the CDF collaboration - the forward-backward…

High Energy Physics - Phenomenology · Physics 2011-08-08 K. S. Babu , Mariana Frank , Santosh Kumar Rai

We study the flavor-dependent chiral U(1)' model where only the right-handed up-type quarks are charged under U(1)$^\prime$ and additional Higgs doublets charged with U(1)' charges are introduced to give proper Yukawa interactions. We find…

High Energy Physics - Phenomenology · Physics 2012-08-24 P. Ko , Yuji Omura , Chaehyun Yu

We perform a model independent analysis on $q \bar{q} \rightarrow t \bar{t}$ using an effective lagrangian with dim-6 four-quark operators, and derive necessary conditions on new physics that are consistent with the $t\bar{t}$ production…

High Energy Physics - Phenomenology · Physics 2011-09-08 Dong-won Jung , P. Ko , Jae Sik Lee , Soo-hyeon Nam

A larger than expected forward-backward asymmetry in rapidity is observed in top quark pairs produced in proton-antiproton collisions at the Tevatron. The asymmetry is seen in both the top quark distribution $A_{FB}^t$ and in the…

High Energy Physics - Phenomenology · Physics 2011-11-18 Edmond L. Berger , Qing-Hong Cao , Chuan-Ren Chen , Jiang-Hao Yu , Hao Zhang