Related papers: New physics in e+ e- -> Z gamma with polarized bea…
The effects of CP violating anomalous ZZZ and gammaZZ vertices in ZZ production are determined. We present the differential cross-section for e+e- -> ZZ with dependence on the spins of the Z bosons. It is shown that from the different spin…
New CP-violating asymmetries of decay leptons in $e^+\,e^-\;\ra\;t\,\bar{t}$, arising from electric and weak dipole couplings of $t\,\bar{t}$ to $\gamma$ and $Z$, are examined in the case of unpolarized and longitudinally polarized…
The capability of the NLC in the $\gamma e$ collider mode to probe the CP-conserving $\gamma WW$ and $\gamma ZZ$ anomalous couplings through the use of the polarization asymmetry is examined. When combined with other measurements, very…
Transverse polarization (TP) can be used to study interference of (S,P) or T type couplings from new physics with the SM contribution. In e+e- -> t tbar, a CP-odd azimuthal asymmetry can constrain the scale Lambda of new (S,P) or T contact…
We study the potential of the next-generation $e^+ e^-$ linear colliders with longitudinally polarized beams, to restrict the values of the anomalous trilinear couplings $WW\gamma$ and $WWZ$ from the measurement of the process $e^+ e^-\to…
We examine the capability of the NLC in the $\gamma e$ collider mode to probe the CP-conserving $\gamma WW$ and $\gamma ZZ$ anomalous couplings through the use of the polarization asymmetry. When combined with other measurements, very…
We examine very general four-point interactions arising from new physics and contributing to the Higgs production process e+e- -> HZ. We write all possible forms for these interactions consistent with Lorentz invariance. We allow the…
Forward-backward asymmetry in the process $e^+ e^- \rightarrow \gamma Z$ is proposed as a test for $CP$--violating anomalous $\gamma \gamma Z$ and $ \gamma Z Z$ couplings. Longitudinally polarized electron beams may be used to disentangle…
We revisit the process $e^+e^- \to \gamma Z$ at the ILC with transverse beam polarization in the presence of anomalous CP-violating $\gamma Z Z$ coupling $\lambda_1$ and $\gamma \gamma Z$ coupling $\lambda_2$. We point out that if the…
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…
We propose to test the CP symmetry in the reactions Z -> mu+ mu- gamma and Z -> tau+ tau- gamma. The experimental analysis of angular correlations allows to determine a set of effective couplings: the electric and weak dipole moments of the…
CP-violating asymmetries due to a possible electric dipole interaction of the top quark in the production and subsequent decay of top quark-top antiquark pair in photon-photon collisions are studied. The asymmetries defined can be used to…
We extend our previous analysis of the sensitivity of the energy dependence of the polarization asymmetry in $\gamma e \to W\nu$ to the possible existence of anomalous trilinear gauge couplings to the $\gamma e \to Ze$ case. We find that by…
An effective anomalous CP-violating Z-gamma-gamma coupling can give rise to observable CP-odd effects in gamma gamma -> t bar{t}. We study certain asymmetries in the decay lepton distributions in gamma gamma -> t bar{t} arising from top…
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…
We consider the possibility of studying anomalous contributions to the gamma-gamma-H and Z-gamma-H vertices through the process e-gamma--> e-H at future e-gamma linear colliders, with Sqrt(S)=500-1500 GeV. We make a model independent…
Beam polarization at e+ e- linear colliders will be a powerful tool for high precision analyses. Often it is assumed that the full information from polarization effects is provided by polarization of the electron beam and no further…
We study possible CP-violation effects of the 125 GeV Higgs to $Z$ boson coupling at the 250 GeV ILC with transverse and longitudinal beam polarisation via the process $e^+ e^- \rightarrow HZ \rightarrow H \mu^-\mu^+$. We explore the…
We analyze possible CP-violating effects induced in the $Z$ decay with hard photon radiation by $\gamma ZZ$ and $\gamma\gamma Z$ anomalous vertices. We estimate the sensibility of future linear collider experiments on these couplings coming…
We investigate the sensitivity of future linear collider experiments to CP violating $WW\gamma$ couplings in the process $e^{+}e^{-} \to \nu\bar{\nu}\gamma$. We consider several sets of machine parameters: centre of mass energies $\sqrt{s}$…