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Related papers: One-side forward-backward asymmetry at the LHC

200 papers

We suggest that the forward-backward asymmetry $(A_{FB})$ of the charged leptons in $gg\to H\to\gamma Z\to\gamma \ell^-\ell^+$ process could be used to probe the CP violating $H\gamma Z$ coupling when the interference from $gg\to\gamma…

High Energy Physics - Phenomenology · Physics 2021-01-07 Xuan Chen , Gang Li , Xia Wan

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

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

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

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

We study contributions of a scalar diquark particle in a color representation of anti-triplet and sextet to the top quark pair production at the Tevatron and the Large hadron collider (LHC). The model can give Forward-Backward (FB)…

High Energy Physics - Phenomenology · Physics 2015-06-05 Kaoru Hagiwara , Junya Nakamura

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

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 present the complete calculations of the forward-backward asymmetry ($A_{\rm FB}$) and the total cross section of top quark pair production induced by dimension-six four quark operators at the Tevatron up to…

High Energy Physics - Phenomenology · Physics 2015-05-28 Ding Yu Shao , Chong Sheng Li , Jian Wang , Jun Gao , Hao Zhang , Hua Xing Zhu

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

The determination of the $Zb\bar{b}$ coupling in experiments has been a long-standing challenge, as the limited precision of off $Z$-pole measurements at the LEP has resulted in two degenerate solutions remained to be resolved. In this…

High Energy Physics - Phenomenology · Physics 2023-07-18 Bin Yan , C. -P. Yuan , Shu-Run Yuan

Several recent measurements at the Tevatron experiments point towards an anomalously large forward-backward asymmetry in top-antitop production. This article summarizes the main classes of physics beyond the standard model that can give…

High Energy Physics - Phenomenology · Physics 2011-08-18 Susanne Westhoff

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 updated CDF measurement of the forward-backward asymmetry (FBA) in the top quark production p{bar p} -> t{bar t} at Tevatron (with the CMS energy 1.96 TeV) shows a deviation of 2*sigma from the value predicted by the Standard QCD Model.…

High Energy Physics - Phenomenology · Physics 2011-04-28 Chuan-Hung Chen , G. Cvetic , C. S. Kim

An extra $U(1)'$ model with $Z'$ coupled only to the right-handed (RH) up-type quarks has been one of the popular models for the Tevatron top forward-backward asymmetry (FBA), and has been excluded by the same-sign top-pair productions at…

High Energy Physics - Phenomenology · Physics 2015-06-15 P. Ko , Yuji Omura , Chaehyun Yu

We present the first measurement of the integrated forward-backward charge asymmetry in top-antitop quark pair (ttbar) production in proton-antiproton collisions in the lepton plus jets final state. Using a b-jet tagging algorithm and…

High Energy Physics - Experiment · Physics 2008-11-26 D0 Collaboration , V. M. Abazov

We calculate the forward backward asymmetry of the top-pair production at TEVATRON up to next to leading order (NLO) in the little Higgs model (LHM). We find that the contribution of $Z_H$ can be large enough to make up the gap between…

High Energy Physics - Phenomenology · Physics 2013-09-24 Xing-Dao Guo , Yin-Jie Zhang , Shu-Min Zhao , Tai-Fu Feng , Xu-Hao Yuan , Xue-Qian Li

The forward-backward asymmetry (FBA) in top-pair production that was observed in 2008 gets a boost in a recent CDF publication. Not only has the FBA further been confirmed, but also distributional preferences are shown. Strikingly, the FBA…

High Energy Physics - Phenomenology · Physics 2015-03-17 Kingman Cheung , Tzu-Chiang Yuan

Many new physics models predict the existence of TeV-scale charged gauge boson $W^\prime$ together with Higgs boson(s). We study the $W^\prime WH$ interaction and explore the angular distribution of charged lepton to distinguish $W_R^\prime…

High Energy Physics - Phenomenology · Physics 2011-06-13 Shou-Shan Bao , Hong-Lei Li , Zong-Guo Si , Yu-Feng Zhou

Reconstructable final state kinematics and charge assignment in the reaction ppbar->ttbar allows tests of discrete strong interaction symmetries at high energy. We define frame dependent forward-backward asymmetries for the outgoing top…

High Energy Physics - Experiment · Physics 2010-05-12 CDF Collaboration , T. Aaltonen