相关论文: CP violating anomalous top-quark couplings at the …

We study the contributions of the CP violating anomalous WW-gamma interactions to b->s l^+ l^-. We obtain cutoff independent results on tilde kappa and tilde lambda, by constructing an asymmetry for the process B->K^*l^+l^-, where the B and…

The lepton or baryon number violating top quark interactions in the supersymmetric standard model with R parity violation contribute to the process d dbar to t tbar at the tree level via the t- or u-channel sfermion exchange. Since these…

We investigate the potential of a high-energy $\gamma\gamma$ collider to detect an anomalous $\bar t q \gamma$ coupling from observation of the reaction $\gamma \gamma \to t\bar q$, $\bar t q$, where $q=c$ or $u$. We find that with…

The combination of the latest and most precise measurements of several top quark properties is presented in this paper in order to establish allowed regions on anomalous contributions to the Lorentz structure of the $Wtb$ vertex. These…

We study the potential of future lepton colliders to probe violation of the CP symmetry in the top quark sector. In certain extensions of the Standard Model, such as the two-Higgs-doublet model (2HDM), sizeable anomalous top quark dipole…

We consider a general two-Higgs-doublet model with CP violation in the scalar sector. Three neutral Higgs fields of the model all mix and the resulting physical Higgs bosons have no definite CP properties. That leads, at the one-loop level…

Search for new-physics through possible anomalous t tbar gamma, tbW and gamma gamma H couplings which are generated by SU(2) X U(1) gauge-invariant dimension-6 effective operators is discussed, using energy and angular distributions of…

A striking manifestation of CP violation in the electroweak symmetry breaking sector would be the existence of neutral Higgs boson(s) with undefined CP parity. We analyse signatures of such a boson, with a mass of about 300 GeV or larger,…

We study momentum distributions of the final-state charged lepton in ppbar/pp --> ttbar --> l^+ X (l=e or mu) at hadron colliders, i.e., Tevatron and Large Hadron Collider (LHC) in order to explore possible new-physics effects in the…

We study the effects of top-Higgs anomalous coupling in the production of a pair of Higgs boson via gluon fusion at the Large Hadron Collider (LHC). The introduction of anomalous $ttH$ coupling can alter the hadronic double Higgs boson…

The general production {\it and} decay mechanism of $\ttbar$ in future high-energy $\epem$ colliders has been investigated in a model-independent way, focusing on an observation of possible CP violation. Angular asymmetries sensitive to CP…

We study effects of CP violation in the associated production of a charged Higgs boson and a top quark at the LHC, $pp \to tH^\pm + X$. We calculate the CP violating asymmetry between the total cross section for $H^+$ and $H^-$ production…

We discuss how to construct genuine CP-odd observables at the LHC. We classify the observables according to the even and odd properties under the naive T-transformation (\hat{T}). There are two classes of observables of our interests:…

Many new physics models beyond the standard model ($SM$) can give rise to the large anomalous top couplings $tqg$ ($q=u$ and $c$). We focus our attention on these couplings induced by the topcolor-assisted technicolor ($TC2$) model and the…

The processes $pp/ pbar p \to Z \gamma + X \to \ell^+ \ell^- \gamma + X$ ($\ell=e, \mu$) and $pp/ pbarp \to Z \gamma + X \to \bar\nu\nu\gamma + X$ are calculated to ${\cal O}(\alpha_s)$ for general $ZZ\gamma$ and $Z\gamma\gamma$ couplings.…

As a top-factory, the LHC is performing a direct study of top-quark anomalous FCNC couplings, which are, however, correlated closely with the rare B- and K-meson decays. In this paper, we study the effects of anomalous $tqZ$ (with $q=u,c$)…

We consider direct bounds on the coefficients of higher dimensional top quark dipole operators from their contributions to anomalous top couplings that affect some related processes at the LHC. Several observables are studied. In…

We discuss the prospects - within several models - for the observation of CP-violation (CPV) in top decays and production. The outlook looks best for t -> bW at the LHC (MSSM CPV), t -> b \tau \nu_\tau at TeV3, LHC and NLC (H^+ CPV), p…

We study the general Higgs-weak boson coupling with CP-violation via the process e+e- -> f \bar f h. We categorize the signal channels by sub-processes Zh production and ZZ fusion and construct four CP asymmetries by exploiting polarized…

We show that a search for $e^+ e^- \to t \bar q$ $(\bar q = \bar c, \bar u)$ events at LEP--2 collider provide a possibility to improve significantly the modern constraints on coupling constants of anomalous $t$--quark interaction via…