Related papers: Measuring Top Quark Electroweak Dipole Moments
The production of top quark pairs in association with a hard gluon in $e^+e^-$ collisions at the NLC provides an opportunity to probe for anomalous $t\bar tg$ couplings, \eg, the chromoelectric and chromomagnetic moments of the top. We…
We consider, both for unpolarized and longitudinally polarized electron beams, the production of a top quark pair in e+e- collisions with subsequent semileptonic top and nonleptonic anti-top decay and vice versa and investigate optimized…
We determine the real parts of electroweak matching conditions relevant for top quark pair production close to threshold in e+e- annihilation at next-to-next-to-leading logarithmic (NNLL) order. Numerically the corrections are comparable to…
We present predictions at NLO accuracy in QCD for top-quark pair production induced by an anomalous chromomagnetic dipole moment of the top quark. Our results are obtained for total as well as fully differential cross sections, including…
We analyze the prospects of probing the $CP$-odd $i \tilde \kappa \bar t \gamma^5 t h$ interaction at the LHC and its projected upgrades, the high-luminosity and high-energy LHC, directly using associated on-shell Higgs boson and top quark…
The cross section for $e^-e^- \to e^-e^-$ with arbitrary electron polarizations is calculated within the Electroweak Standard Model for energies large compared to the electron mass, including the complete virtual and soft-photonic…
The production of top quark pairs is one of the most relevant production modes at the LHC, and allow for precise measurement of the properties of this particle. Top quarks are also produced through rarer mechanisms, including the production…
Vectorial partners of the Standard Model quarks and leptons are predicted in many dynamical models of electroweak symmetry breaking. The most easily accessible of these new particles, either due to mass or couplings, are typically expected…
We study the $W$ boson associated single top quark production at the Large Hadron Collider (LHC) to probe anomalous chromo-magnetic and chromo-electric moments of the top quark with the help of polarization and spin correlation observables…
We show numerically that quarks develop an electric dipole moment in the direction of a sufficiently intense magnetic field due to local fluctuations of topological charge. This anomalous CP-odd effect is a spin analogue of the Chiral…
A number of top-spin observables are computed within the Standard Model (SM), at next-to-leading order in the strong and weak gauge couplings for hadronic top-quark anti-quark (ttbar) production and decay at the LHC for center-of-mass…
We study the mechanism of single top production at the LHC in the framework of an effective electroweak Lagrangian, analyzing the sensitivity of different observables to the magnitude of the effective couplings that parametrize new physics…
We present a detailed investigation of the NLO polarization of the top quark in t t-bar production at a polarized linear e^+ e^- collider with longitudinally polarized beams. By appropiately tuning the polarization of the beams one can…
With initial and final particles on-shell, the anomalous weak-magnetic dipole moments of b and c quarks are electroweak gauge invariant quantities of the effective couplings Zb\bar{b} and Zc\bar{c}, respectively, and good candidates to test…
With the recent discovery of a heavy top quark $(m_t \approx 175 - 200$ GeV), the top quark opens an window to electroweak symmetry breaking. We propose the study of four-top, $t\bar t t\bar t$, production at hadronic supercolliders as a…
We show that the measurement of the $Z$ polarization in the $e^+e^-\to t\bar t Z$ process would allow an interesting determination of the role of the top quark mass. This can be used for testing the possibility of top compositeness or of…
The measurement of the top-quark anomalous electromagnetic couplings is one of the most important goals of the top-quark physics program in the present and future collider experiments. This would provide direct information on the…
For a twisted (vortex) Dirac particle in nonuniform electric and magnetic fields, the relativistic Foldy-Wouthuysen Hamiltonian is derived including high order terms describing new effects. The result obtained shows for the first time that…
Single top-quark production, via weak-interaction processes, is an important test of the standard model, potentially sensitive to new physics. However, this measurement is much more challenging at the Tevatron than originally expected. We…
In the presence of an electric dipole coupling of the top quark to a photon, and an analogous "weak" dipole coupling to the Z, CP violation in the process e+e- -> t tbar leads to the polarization of the top and anti-top. This polarization…