Related papers: Probing Form Factors in Top Quark Pair Production …
In terms of an effective Lagrangian we investigate the possibilities of probing anomalous top quark couplings, $t \bar{t} H$, $\gamma t \bar{t}$, $Z t \bar{t}$ and $tWb$ at the future linear colliders. It is found that probing anomalous top…
The effect of new operators that give rise to CP-violating couplings of the type $Z t \bar{t}$ and $\gamma t \bar{t}$ are examined at future electron positron Linear Colliders (FLC). The impact of these CP-violating interactions over…
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 process of top-quark pair production followed by semileptonic decays at future high-energy e^+e^- linear colliders is investigated as a possible test of physics beyond the Standard Model. Assuming the most general non-standard forms for…
The top quark plays a central role in many New Physics scenarios and in understanding the details of Electro-Weak Symmetry Breaking. In the short- and mid-term future, top-quark studies will mainly be driven by the experiments at the Large…
We analyze the pair-production of top quarks in polarized $e^+e^-$ scattering in the presence of electroweak dipole moments. For this, we consider two $CP$-odd observables which probe both the real and the imaginary parts of these moments.…
We obtain analytical formulae for the cross section and the angular distributions of the b(bbar) quarks in the process e+e- -> t tbar, with t -> W+ b (tbar -> W- bbar) assuming CP violation in the \gamma t tbar and Z t tbar vertices. We…
In the littlest Higgs model with T-parity, we studied the contributions of the new particles to the top-quark pair production via $e^{+}e^{-}$ collision at the International Linear Collider. We calculated the top-quark pair production cross…
The energy spectra of the b and bbar quarks in e+e- -> t tbar with t -> b W (tbar -> bbar W) are calculated assuming CP violation in the production process. Expressions for the corresponding CP violating asymmetries and optimal observables…
The capability of the LHC to study the electromagnetic dipole moments of the top quark is discussed. In particular, the process $pp\to p\gamma\gamma p\to pt\bar{t}p$, which is supposed to be tagged by the forward/backward detectors at the…
An optimal-observable analysis of the angular and energy distributions of the leptons and bottom quarks in the process e+e- --> tt-bar --> l^{+-}/b(b-bar)... has been performed in order to measure the most general top-quark couplings to…
Due to the very large mass of the top-quark, probing the flavor changing top-charm-scalar vertex is clearly very important. Fortunately the largeness of $m_t$ endows a unique signature to the resulting reaction i.e., $e^+e^-\to t\bar c…
Our main aim in this paper is to constrain the effective field theory describing the top quark couplings through the $e^{-} e^{+} \rightarrow t \bar{t}+$jet process. The analysis is carried out considering two different center-of-mass…
We report on an investigation of CP violation in (un)polarized $e^+e^-\to{\bar t}t$ resulting from an extended neutral Higgs sector or from the minimal SUSY extension of the Standard Model (SM). We consider c.m. energies from the ${\bar…
We studied the process $e^{+}e^{-} \to t\bar{c}+c\bar{t}$ in a R_{p} violating supersymmetric model with effects from both B- and L-violating interactions. The calculation shows that it is possible to either detect the R_{p} violating…
The single production of leptoquarks in $e^+e^-$, $e\gamma$ and $\gamma \gamma$ linear colliders is discussed. We show that these new particles could be seen in such machines even if their mass is close to the kinematic limit. (Invited talk…
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…
One of the main endeavors at future high-energy colliders is the search for the Higgs boson(s) and, once found, the probe of the fundamental properties. In particular, the charge conjugation and parity (CP) quantum numbers have to be…
Determination of the top-quark Yukawa couplings in the process e+ e- -> t \bar{t} Z has been studied for the high luminosity option (\int L=500\fbinver) of a linear e+e- collider. Polarization of the electron beam has been considered. The…
We study production of t {\bar t} via W^+ W^- fusion, including the relevant backgrounds at the proposed Linear Collider (an e^+ e^- collider with \sqrt{S} = 1.5 TeV) in the context of a Higssless Standard Model (SM), i.e. a nonlinear…