Related papers: Polarization and spin correlations of top quarks a…
We compute the supersymmetric QCD corrections to the polarization and the spin correlations of top quarks produced above threshold in e+e- collisions, taking into account arbitrary longitudinal polarization of the initial beams.
We discuss in detail top quark polarization in above-threshold (t \bar t)-production at a polarized linear e^+ e^- collider. We pay particular attention to the minimization and maximization of the polarization of the top quark by tuning the…
We discuss the prospects to observe effects of transverse polarization and spin-spin correlations of top quark pairs produced at hadron colliders.
The object of this thesis is to study the spin-spin correlations for top quark productions and their decay at polarized e^+e^- linear colliders. For the analyses of the spin-spin correlations in top quark production, we introduce a generic…
I review the studies, which were reported after the last Linear Collider Workshop, on top quark physics and QCD physics at a future e+e- linear collider.
We show that top-quark pairs are produced in an essentially unique spin configuration in polarized $e^+e^-$ colliders at all energies above the threshold region. Since the directions of the electroweak decay products of polarized top-quarks…
We investigate the spin correlations in top quark pair production near threshold at the $ e^- e^+ $ linear collider. Comparing with the results above the threshold region, we find that near the threshold region the off-diagonal basis, the…
Spin correlations, using a generic spin basis, are investigated to leading order in QCD for top quark production at lepton colliders. Even though, these radiative corrections induce an anomalous gamma/Z magnetic moment for the top quarks…
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_- =…
Future hadron collider experiments will allow for a detailed investigation of $t\bar{t}$ spin correlation effects. In this talk, recent progress in the theoretical description of these effects is reported. In particular, next-to-leading…
We study the spin properties of top quarks produced in collisions of polarized photons in the threshold region. For a relatively heavy top quark the influence of non-perturbative effects is small and its polarization parameters can be…
The top quark pairs produced at a polarized muon collider are in a (nearly) pure spin configuration. This result holds for all center-of-mass energies, and is insensitive to the next-to-leading order QCD radiative corrections. The decay…
We analyze spin correlations between top quark and anti-top quark produced at polarized e^+ e^- and gamma gamma colliders. We consider a generic spin basis to find a strong spin correlation. Optimal spin decompositions for top quark pair…
We present the full O(alpha_s) longitudinal spin-spin correlations for heavy-quark pair production at e+ e- high-energy colliders in closed analytical form. In such reactions, quark and antiquark have strongly correlated spins, and the…
We analyze the spin correlations of the top quark pairs produced at Photon Linear Colliders. We employ the circular polarized photon beams and general spin basis for the top quark pair. We consider general spin bases to find a strong spin…
We investigate the degree of spin polarization of single top quarks in the $e\gamma$ collision via the process $e^{+} \gamma \to t \bar{b} \bar{\nu_{e}}$ with center of mass energies $\sqrt{s}$=0.5, 1 and 1.5 TeV of the parental linear…
Top quark pairs are produced with strongly correlated spins in the partonic reactions $q\bar{q}\to t\bar{t}$ and $gg\to t\bar{t}$. A complete description of these effects in terms of the spin density matrix of the $t\bar{t}$ system in…
We investigate the effects of scalar and vector unparticles on top quark spin correlations via the process $e^{+}e^{-}\to t \bar{t}$. In addition to the Standard Model diagrams, there is a new contribution to top-antitop quark production…
In this contribution I review the physics of top quarks at a future Linear Collider. Main emphasis is put on the process e+ e- to ttbar close to threshold. Different physical observables, their sensitivity to the basic parameters and their…
The theoretical aspects of spin correlations in top quark pair production are briefly reviewed.