Related papers: Singlet quarks beyond the top at the Tevatron?
The top quark is one of the least well-studied components of the standard model. In these lectures I discuss the expected properties of the top quark, which will be tested at the Fermilab Tevatron and the CERN Large Hadron Collider. I begin…
A search for the production of heavy partners of the top quark with charge 5/3 is performed in events with a pair of same-sign leptons. The data sample corresponds to an integrated luminosity of 19.5 inverse femtobarns and was collected at…
After a brief comment on the role of top quark in models of electroweak symmetry breaking (EWSB), I shall discuss what we know about top quark interaction and how to improve that knowledge. Since bottom quark is the weak isospin partner of…
We present first evidence for the production of single top quarks at the Fermilab Tevatron {\ppbar} collider. Both D0 and CDF experiments have measured the single top production cross section with a 3-standard-deviation significance using…
Recent results from CDF indicate that the inclusive cross section for jets with $E_T > 200$ GeV is significantly higher than that predicted by QCD. We describe here a simple flavor-universal variant of the ``coloron" model of Hill and Parke…
The techniques used to study top quarks at hadron colliders are presented. The analyses that discovered the top quark are described, with emphasis on the techniques used to tag b-quark jets in candidate events. The most recent measurements…
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…
The CDF and D0 collaborations have both reported unusual events in the dilepton+jets sample with very high lepton and missing transverse energies. It is possible, but very unlikely, that these events originate from top quark pair…
The top asymmetries measured at the Tevatron, and the discrepancy in the di-photon Higgs rate under investigation at the LHC represent two possible hints of physics beyond the Standard Model (SM). In this paper we address the possibility to…
Single production of top quarks at hadron colliders via $gW$ fusion is examined as a probe of possible anomalous chromomagnetic and/or chromoelectric moment type couplings between the top and gluons. We find that this channel is far less…
We investigate existing and future hadron-collider constraints on the top dipole chromomagnetic and chromoelectric moments, two quantities that are expected to be modified in the presence of new physics. We focus first on recent…
The CDF and D0 experiments at the Fermilab Tevatron have discovered the top quark and provided first measurements of many of its properties. The small top sample gathered by Run I leaves open many possibilities for top physics beyond the…
Scalar induced top decays may drastically suppress $B(t\to \ell\nu + jet)$ and still hide the top below $M_W$. The $p\bar p$ collider experiments should enlarge the scope and study the $m_t - B(t\to\ell\nu j)$ plane. Specific model…
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)…
We present the results of a detailed study of the effects of $b$-tagging on the heavy top-quark signal and backgrounds for the modes of the di-lepton plus two high transverse energy jets at the Fermilab Tevatron. The general characteristics…
Spin correlations of top quarks produced in hadron collisions have not been observed experimentally with large significance. In this Letter, we propose a new variable that may enable demonstration of the existence of spin correlations with…
The D0 Collaboration presents first evidence for the production of single top quarks at the Fermilab Tevatron ppbar collider. Using a 0.9 fb^-1 dataset, we apply a multivariate analysis to separate signal from background and measure…
This paper reports on the first observation of electroweak production of single top quarks by the DZero and CDF collaborations. At Fermilab's 1.96 TeV proton-antiproton collider, a few thousand events are selected from several inverse…
We know there is new physics at the electroweak scale, but we don't know what it is. Right now, the top quark is our only window on to this physics. In almost all models of electroweak symmetry breaking, top either couples strongly to new…
The existence of new vector-like quarks is often predicted by models of new physics beyond the Standard Model, and the development of discovery strategies at colliders is the object of an intense effort from the high-energy community. Our…