Related papers: CP violation in open ttbar production at a linear …
We study in a model-independent way anomalous CP-violating tbW effective couplings that might arise from new physics in the processes pp-> tW^- X and pp-> tbar W^+X, followed by semileptonic decay of t and tbar. These processes have a…
We consider a general two-Higgs-doublet model with CP violation in the scalar sector, that leads, at the one-loop level of the perturbation expansion, to CP-violation in the process $e^+e^- \to t\bar{t} \to l^\pm ...$ and $e^+e^- \to…
In this talk I review how to search for CP violation in top-quark pair production and decay using T-odd correlations. I discuss two examples which illustrate many of the relevant features: CP violation in a heavy neutral Higgs boson; and CP…
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 report our theoretical study on how to probe the anomalous CP-violating couplings of the top quark in the ttbar region at future e+e- linear colliders. We focus on the unique role of the ttbar threshold region.
The process of top-quark pair production at future high-energy $e^+ e^-$ linear colliders has been investigated as a possible test of physics beyond the Standard Model. Non-standard interactions have been assumed both for the production and…
In order to observe a signal of possible CP violation in top-quark couplings, we study top-quark production and decay under the conditions of the Tevatron upgrade. Transverse energy asymmetries sensitive to CP violation are defined.…
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 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…
We consider the most general gauge-invariant, chirality-conserving contact interactions in the process e +e- -> gamma Z, of the type proposed Abraham and Lampe, in order to explore the possibility of CP violation at future linear colliders…
We study how to probe the anomalous CP-violating couplings of top quark with photon, Z and gluon in the ttbar threshold region at future e+e- colliders. These couplings contribute to the difference of the t and tbar polarization vectors…
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…
CP violation in the decays $t \to \ell^+\nu b$ and $\bar t \to \ell^-\bar\nu \bar b$ from the production process $e^-e^+ \to \ttbar$ is discussed. Since the asymmetry proposed as a measure of CP violation vanishes even at the one-loop level…
We discuss the observability of CP-violating asymmetries in the process e+ e- -> X_1^0 X_2^0 -> X_1^0 X_1^0 l+ l-, with l = e,mu. We consider two examples of supersymmetric scenarios: (i) with decays X_2^0 -> l_R l -> X_1^0 l+ l-; (ii) with…
We study the possibility of a large CP/T-violation in lepton pair production in the collisions of polarized protons at RHIC-BNL. We propose the single transverse spin asymmetry which quantifies the possible CP/T-violating effect in this…
We review CP violation in various extensions of the electroweak sector of the Standard Model. A particular emphasis is put on supersymmetric models. We describe the two CP problems of supersymmetry, concerning $d_N$ and $\epsilon_K$. We…
We study the T odd correlations induced by CP violating anomalous top-quark couplings at both production and decay level in the process gg --> t t_bar --> (b mu+ nu_mu) (b_bar mu- nu_mu_bar). We consider several counting asymmetries at the…
We examine very general four-point interactions arising due to new physics contributing to the Higgs production process e+e- --> HZ. We write all possible forms for these interactions consistent with Lorentz invariance. We allow the…
We propose T-odd and CP-odd odd asymmetries in order to analyze the impact of CP violating phases in neutralino production and subsequent leptonic two-body decays. We present numerical results of these asymmetries and of the cross sections…
It is shown that if electron and positron beams at a linear collider are transversely polarized, azimuthal asymmetries of the final-state top quark in e+e- --> t tbar can be used to probe a combination of couplings of left and right…