相关论文: Top Pair Forward-Backward Asymmetry from Loops of …
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…
Both D0 and CDF at Tevatron reported the measurements of forward-backward asymmetry in top pair production, which showed possible deviation from the standard model QCD prediction. In this paper, we explore how to examine the {\em same}…
The large forward-backward asymmetry of the top quark pair production measured by the hadron colliders shed light on new physics signals beyond the Standard Model. In the Randall-Sundrum model with an additional SU(3) group in the strong…
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…
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…
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…
We present the results of a search for pair production of a new heavy top-like quark t' decaying to a W boson and another quark using the CDF II detector in Run II of the Tevatron proton-antiproton collider. Using a data sample…
In the $pp \rightarrow t\bar{t}$ process the angular distributions of top and anti-top quarks are expected to present a subtle difference, which could be enhanced by processes not included in the Standard Model. This Letter presents a…
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…
The results of a search for pair production of a heavy, top-like quark, t', in the decay mode (t' anti-t') to (b anti-W anti-b W) to (b anti-lepton neutrino anti-b lepton anti-neutrino) are presented. The search is performed with a data…
In this article, I review recent measurements of the production of the top quark in $p\bar p$ collisions at a centre-of-mass energy of $\sqrt s=1.96$~TeV in Run II of the Fermilab Tevatron Collider, recorded by the CDF and D0…
We study the production of a single top quark in association with a heavy extra $Z'$ at hadron colliders in new physics models with and without flavor-changing neutral-current (FCNC) couplings. We use QCD soft-gluon resummation and…
Both CDF and DO report a forward-backward asymmetry in t-tbar production that is above the standard model prediction. We review new physics models that can give a large forward backward asymmetry in t-tbar production at the Tevatron and the…
Predictions are made for the forward-backward and charge asymmetries in bottom-quark pair production at hadron colliders. Tree-level exchanges of electroweak (EW) gauge bosons dominate the Standard Model (SM) contribution to the asymmetry…
We measure the particle-level forward-backward production asymmetry in $b\bar{b}$ pairs with masses $m(b\bar{b})$ larger than 150 GeV/$c^2$, using events with hadronic jets and employing jet charge to distinguish $b$ from $\bar{b}$. The…
We calculate the electroweak corrections of the order $O({m_t^2\over v^2})$ to the QCD production of $t\bar{t}$ pairs via $q+qbar->t+tbar$ at hadron colliders and show that these corrections to the total production rate are small. This…
A search for pair-produced bottom-like quarks in pp collisions at sqrt(s) = 7 TeV is conducted with the CMS experiment at the LHC. The decay b' to tW is considered in this search. The b' b'-bar to tW^- t-bar W^+ process can be identified by…
We consider top-antitop quark ($t{\bar t}$) production at the Large Hadron Collider (LHC) with subsequent decay into dileptonic and lepton plus jets final states. We present a set of leptonic angular correlations and distributions with…
I present the two-loop QCD corrections to the production of a massive quark-anti-quark pair in the massless quark-anti-quark annihilation channel. The result is obtained as a combination of a deep expansion in the mass around the high…
The charge asymmetry in top quark pair production in the di-lepton $t\bar t$ channel using the ATLAS experiment at Large Hadron Collider is presented. The asymmetry is studied in the distribution of absolute rapidity difference between top…