English
Related papers

Related papers: Top Quark Polarization and the Search for New Phys…

200 papers

Forward-backward asymmetries $A_{FB}^t$ and $A_{FB}^\ell$ are observed in the top quark $t$ rapidity distribution and in the rapidity distribution of charged leptons $\ell$ from top quark decay at the Tevatron proton-antiproton collider,…

High Energy Physics - Phenomenology · Physics 2014-03-11 Edmond L. Berger , Qing-Hong Cao , Chuan-Ren Chen , Hao Zhang

A large forward-backward asymmetry is seen in both the top quark rapidity distribution $A_{FB}^t$ and in the rapidity distribution of charged leptons $A_{FB}^\ell$ from top quarks produced at the Tevatron. We study the kinematic and dynamic…

High Energy Physics - Phenomenology · Physics 2012-02-15 Edmond L. Berger , Qing-Hong Cao , Chuan-Ren Chen , Jiang-Hao Yu , Hao Zhang

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

Recent experimental results from the CDF collaboration which study the top forward-backward asymmetry have strengthened the case that new physics is playing a role in t-tbar production. Here we propose a set of measurements, built from the…

High Energy Physics - Phenomenology · Physics 2013-05-29 David Krohn , Tao Liu , Jessie Shelton , Lian-Tao Wang

We provide the most up-to-date predictions for the top-quark charge asymmetry A_C at the LHC with a centre-of-mass energy of 8 TeV. Our result is accurate at the NNLO level in the strong interactions and at the complete-NLO level in both…

High Energy Physics - Phenomenology · Physics 2018-07-11 Michal Czakon , David Heymes , Alexander Mitov , Davide Pagani , Ioannis Tsinikos , Marco Zaro

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

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

We provide a qualitative and quantitative unified picture of the charge asymmetry in top quark pair production at hadron colliders in the SM and summarise the most recent experimental measurements.

High Energy Physics - Phenomenology · Physics 2014-11-19 Johann H. Kuehn , German 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

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

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

Forward-backward asymmetry $A_{\rm FB}$ is an essential observable to study the nature of coupling in the standard model and physics beyond the standard model, as shown at LEP and Tevatron. As a proton-proton collider, the LHC does not have…

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

The forward-backward asymmetry $A_{FB}^{t\bar t}$ in top quark production at the Tevatron has been observed to be anomalously large by both CDF and D0. It has been suggested that a model with a $W'$ coupling to $td$ and $ub$ might explain…

High Energy Physics - Phenomenology · Physics 2011-09-08 Nathaniel Craig , Can Kilic , Matthew J. Strassler

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

We propose two new observables to measure the charge asymmetry in hadronic top-quark pair production in association with a hard jet. The incline asymmetry, based on the inclination between the planes of initial- and final-state momenta,…

High Energy Physics - Phenomenology · Physics 2013-09-27 Stefan Berge , Susanne Westhoff

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

At the LHC, top quark pairs are dominantly produced from gluons, making it difficult to measure the top quark forward-backward asymmetry. To improve the asymmetry measurement, we study variables that can distinguish between top quarks…

High Energy Physics - Phenomenology · Physics 2015-05-28 Yang Bai , Zhenyu Han

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

A sizeable difference in the differential production cross section of top- compared to antitop-quark production, denoted charge asymmetry, has been observed at the Tevatron. The experimental results seem to exceed the theory predictions…

High Energy Physics - Phenomenology · Physics 2015-05-30 Johann H. Kuhn , German Rodrigo

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
‹ Prev 1 2 3 10 Next ›