Related papers: Is $M_t\simeq M_w$ Ruled Out?
The results of a search for the pair production of a fourth-generation up-type quark (t') in proton-proton collisions at sqrt(s) = 7 TeV are presented, using data corresponding to an integrated luminosity of about 5.0 inverse femtobarns…
Simple models are proposed where the baryon and lepton number are gauged and spontaneously broken near the weak scale. The models use a fourth generation that is vector-like with respect to the strong, weak and electromagnetic interactions…
If next generations of heavy quarks and leptons exist within the standard model (SM), they can manifest themselves in Higgs boson production at the Tevatron and the LHC, before being actually observed. This generation leads to an increase…
We search for pair production of supersymmetric top quarks (~t_1), followed by R-parity violating decay ~t_1 -> tau b with a branching ratio beta, using 322 pb^-1 of ppbar collisions at sqrt{s}=1.96 TeV collected by the CDF II detector at…
Following the confirmation of the top quark discovery at the Tevatron, the next step is to begin studying its properties. Because the scale of electroweak symmetry breaking is of the same order as the measured top mass, the top quark may be…
Analyzing the $\ell +n$-$jets+ \met$ (where $n \ge 2 $), data from Run-I of the Tevatron using the Bayesian technique, we obtain model independent limits on the product $\br(\lstop\ra be^{+}\nu_e \lspone) \times \br(\lstop^{*}\ra…
An overview of recent top quark measurements using the full Run II data set of CDF or D0 at the Tevatron is presented. Results are complementary to the ones at the LHC. Recent measurements of the production cross section of top quarks in…
We summarize the Standard Model predictions for the three-body decays of the top quark t->WbX, where X = Z,H,g or gamma. Because of strong phase space suppression, we find that the branching ratios for the Z and H final states are of order…
Top quark decays are of particular interest as a mean to test the standard model (SM) predictions, both for the dominant ($t\to b+W$) and rare decays ($t\to q+W, cV, cVV,c\phi^0,bWZ$). As the latter are highly suppressed, they become an…
We point out that events with 6 or more top quarks may be observed at the LHC if certain particles exist at the TeV scale. In a model where a vectorlike quark of charge 2/3 decays into a top quark and a pseudoscalar particle, which…
A new approach towards the composite structure of quarks and leptons in the context of the higher dimensional unified theories is proposed. Owing to the certain strong dynamics, much like an ordinary QCD, every possible vectorlike…
In this document we present several recent (July 2008) results from studies of the top quark properties at the CDF and D0 experiments at the Tevatron. Measurements of several top quark properties, as well as tests of new physics in the top…
We present results for the production of a top pair in association with a W-boson at next-to-leading order. We have implemented this process into the parton-level integrator MCFM including the decays of both the top quarks and the W-bosons…
Precise measurements of the properties of the top quark test the Standard Model (SM) and can be used to constrain new physics models. The top quark pair charge asymmetry is an asymmetry predicted to occur beyond leading-order QCD in the SM,…
We present first evidence for the production of single top quarks in the D0 detector at the Fermilab Tevatron ppbar collider. The standard model predicts that the electroweak interaction can produce a top quark together with an antibottom…
We describe the implementation of top production and decay processes in the parton-level Monte Carlo program MCFM. By treating the top quark as being on-shell, we can factorize the amplitudes for top-pair production, s-channel single-top…
The forward-backward asymmetry $A_{FB}$ in top quark pair production, measured at the Tevatron, is probably related to the contribution of new particles. The Tevatron result is more than a $2\sigma$ deviation from the standard model…
We search for physics beyond the standard model using events with a photon, two or more hadronic jets, and an apparent imbalance in transverse energy, in $p\bar{p}$ collisions at the Fermilab Tevatron at $\sqrt{s}=1.8$ TeV. Such events are…
Top-quark pair production at the Tevatron is discussed within the Randall-Sundrum model of warped extra dimensions. Generically, the exchange of massive Kaluza-Klein gluons has the potential to generate a large forward-backward asymmetry.…
Three aspects of supersymmetric theories are discussed: electroweak symmetry breaking, the issues of flavor, and gauge unification. The heavy top quark plays an important, sometimes dominant, role in each case. Additional symmetries lead to…