Related papers: Polarized Top Quarks
We perform a comparative study of the reach of future $e^+e^-$ collider options for the scale of non-resonant new physics effects in the top quark sector, phrased in the language of higher-dimensional operators. Our focus is on the…
In most of the models beyond the Standard Model, the top quark is expected to be polarized when produced in the decay of some heavier particle, like the gluino or the stop. The polarization is constructed, in an experiment or in…
We evaluate the potential of the CERN LHC collider to observe rare decays of the top quark in channels involving R-parity violating (RPV) interactions. We stress the importance of calculating top quark production and decay simultaneously as…
We discuss the polarization of top quarks produced at a polarized linear e^+ e^- collider. Close-to-maximal values of the top quark polarization can be achieved with longitudinal beam polarizations (h_- = -0.80, h_+ = +0.625) or (h_- =…
In the presence of an electric dipole coupling of $t \bar t$ to a photon, and an analogous ``weak" dipole coupling to the $Z$, $CP$ violation in the process $e^+e^- \rightarrow t \bar t$ leads to the polarization of the top and anti-top.…
The uncertainty of $t\bar{t}$ production cross section measurement at LHC is at a-few-percent level which still allows the stop pair production $\tilde{t}\tilde{t}^{*}$ with identical final states $2b+\ell+nj+{E}_{T}$. In this paper, we…
We study the sensitivity of the Large Hadron Collider (LHC) to top quark chromomagnetic (CMDM) and chromoelectric (CEDM) dipole moments and $Wtb$ effective couplings in single-top production in association with a $W^-$ boson, followed by…
I summarize recent top quark physics results from the Fermilab Tevatron experiments. Since the observation of the top quark by CDF and D0 in 1995, the experimental focus has shifted to a detailed study of the top quark's properties. This…
Spin correlations in the top quark-antiquark system and the polarization of the top quark are measured using dilepton final states produced in pp collisions at the LHC at sqrt(s) = 7 TeV. The data correspond to an integrated luminosity of…
Longstanding puzzles in spin physics can be confronted at the high energies of the LHC. Will large s-quark and c-quark polarization be observed through heavy hyperon production? Top quarks are expected to have significant polarization -…
We study the sensitivity of the Large Hadron Collider (LHC) to top quark chromomagnetic (CMDM) and chromoelectric (CEDM) dipole moments and $Wtb$ effective couplings in single-top production in association with a $W^-$ boson, followed by…
Compact analytic expressions have been obtained for the first order perturbative QCD corrections to the inclusive spectra of the leptons in the semileptonic decays of polarised heavy quarks. Charmed and beautiful $\Lambda$ baryons from…
We establish the existence of the top quark using a 67 pb^-1 data sample of Pbar-P collisions at Sqrt(s) = 1.8 TeV collected with the Collider Detector at Fermilab (CDF). Employing techniques similar to those we previously published, we…
A detailed study of top-quark polarizations and $t \bar t$ charge asymmetries, induced by top-squark-pair production at the LHC and the subsequent decays $\tilde t \to t \tilde \chi_1^0$, is performed within the effective description of…
Analytic expression for energy and angular dependence of a secondary charged lepton in the decay of a polarized top quark with anomalous $tWb$ couplings in the presence of all anomalous couplings are derived. The angular distribution of the…
CP-violating asymmetries in the processes e+e- -> t tbar and gamma gamma -> ttbar can provide information about CP-violating couplings of the top quark, whose presence would signal physics beyond the standard model. Work on studies of…
We investigate the single top quark production with the exchange of unparticles through high energy photon-photon collision $\gamma \gamma\to t \bar c$. The effects of unparticles on the scattering cross sections for different polarization…
New interactions in top-quark production and decay are studied under the conditions of the Tevatron upgrade. Studying the process q qbar --> t tbar --> b mu nu tbar, it is shown how the lepton rapidity and transverse energy distribution are…
Observables sensitive to top quark polarization are important for characterizing or even discovering new physics. The most powerful spin analyzer in top decay is the down-type fermion from the W, which in the case of leptonic decay allows…
Angular and energy distributions for leptons and bottom quarks in the process e+e- --> t tbar --> l/b ... have been calculated assuming the most general top-quark couplings. The double distributions depend both on modification of the…