Related papers: Isolating CP-violating \gamma ZZ coupling in e+e- …
Higgs boson couplings with gauge bosons are probed through $e^-e^+ \rightarrow Z \gamma h$ in an effective Lagrangian framework. For this study the beam polarization facility at the ILC along with the typical center-of-mass energy of 500…
The prime goal of this thesis is to study anomalous gauge boson self couplings, triple gauge boson couplings in particular, with the help of spin polarization observables of the gauge bosons $Z$ and $W^\pm$ in the presence of beam…
The potential of the process $\gamma \gamma \rightarrow \tau \bar{\tau}\gamma$ is examined in a model-independent way using the effective Lagrangian approach for the ILC which is designed with standard configurations of 0.25 TeV/2000…
The non-Abelian gauge structure of the Standard Model implies the presence of the multi-boson self-interactions. Precise measurements in experimental and theoretical studies of these interactions allow not only testing the nature of the…
We study the sensitivity to the Z' couplings of the processes $e^+e^-\to l^+l^-,\bar{b}b$ and $\bar{c}c$ at the linear collider with $\sqrt{s}=500 GeV$ with initial beam polarization, for typical extended model examples. To this aim, we use…
We performed a detailed analysis of the process $e^+e^-\to \ell \nu q\bar{q}'$ where we included all tree level Feynman diagrams that contribute to this final state. We studied the sensitivity of this process to anomalous trilinear gauge…
We study possible new physics interactions in the $ZZH$ vertex contributing to the Higgsstrahlung process $e^+ e^- \to ZH$ at proposed future $e^+e^-$ colliders using the polarization of the $Z$ as a probe. We calculate the spin density…
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…
In view of the very precise measurements on fermion couplings which will be performed at ILC250 with polarized beams, there is emerging evidence that the LEP1/SLC measurements on these couplings are an order of magnitude too imprecise to…
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…
We study anomalous couplings among neutral gauge bosons in $ZZ$ production at the LHC for $\sqrt{s}=13$ TeV in $4$-lepton final state. We use the cross section and polarization asymmetries of the $Z$ boson to estimate simultaneous limits on…
The constraints on anomalous Higgs boson couplings are investigated through the process $\gamma\gamma \to W^{+}W^{-}H$. Considering the longitudinal and transverse polarization states of the final $W^{+}$ and $W^{-}$ bosons and incoming…
We find 95% confidence level limits on the anomalous coupling parameters $a_0$, $a_c$ and $a_n$ with an integrated luminosity of $500fb^{-1}$ and $\sqrt s =0.5, 1$ and 1.5 TeV energies. We take into account incoming beam polarizations and…
We study the anomalous $W^+W^-V$ ($V=\gamma,Z$) couplings in $e^+e^-\to W^+W^-$ using the complete set of polarization observables of $W$ boson with longitudinally polarized electron ($e^-$) and positron ($e^+$) beams. For the effective…
The effect of anomalous chromoelectric couplings of the gluon to the top quark are considered in e+ e- --> t tbar. The total cross section, as well as t and tbar polarizations are calculated to order alpha_s in the presence of the anomalous…
The effect of anomalous chromomagnetic (mu) and chromoelectric couplings (d) of the gluon to the top quark are considered in e+ e- --> t tbar, with unpolarized and longitudinally polarized electron beams. The total cross section, as well as…
The present contribution reports a study of the effects of anomalous gauge and fermionic couplings in the process $e^+e^- -> W^+W^-$ at the Next Linear Collider focusing in particular on the option of polarized beams. We conclude that…
The electroweak CP violating rate asymmetries in the decay $b \to d l^+ l^-$ are reexamined in detail and updated. In particular, the rate asymmetries are studied when one of the final state leptons is polarised. We find an estimate for the…
We study in detail the impact of anomalous Higgs couplings in angular asymmetries of the crossing-symmetric processes H --> Zl+l- and e+e- --> HZ. Beyond Standard Model physics is parametrized in terms of the SU(3)xSU(2)_LxU(1)_Y…
We examine the contribution of general Z*ZH and gamma*ZH three-point interactions arising from new physics to the Higgs production process e+e- -> HZ. From Lorentz covariance, each of these vertices may be written in terms of three…