Related papers: Unique heavy lepton signature at $e^+e^-$ linear c…
One way to detect the presence of new particles in theories beyond the standard model is through their contribution to electroweak loop effects. We comment on the importance of a consistent inclusion of their mixing angles to ensure that…
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…
In this study we investigate the feasibility of detecting heavy neutral leptons ($N_d$) through exotic Higgs decays at the proposed International Linear Collider (ILC), specifically in the channel of $e^+ e^- \to qq~ H$ with $H\to \nu N_d…
In this work we study the production of color-neutral and singly-charged heavy leptons at the proposed International Linear Collider. We use the optimal observable technique to determine the statistical accuracy to which the coupling of…
As a strong candidate for new physics beyond the Standard Model, the exotic charged gauge boson $W^{\prime}$ has attracted extensive research interest. In this work we investigate the interactions of the $W^{\prime}$ boson at the…
We studied the dimension-6 leptonic anomalous gauge couplings in the formulation of linearly realized gauge symmetry effective Lagrangian and investigated the constraints on these anomalous couplings from the existed experimental data…
We investigate the anomalous $W^+W^-\gamma$ couplings through the process $e^-e^+\,\rightarrow\,\nu_e\bar{\nu}_e\gamma$ for unpolarized and polarized electron (positron) beams at the International Linear Collider. We give the 95$\%$…
We investigate the use of beam polarisation as well as final state $\tau$ polarisation effects in probing the interaction of the Higgs boson with a pair of heavy vector bosons in the process $e^+ e^- \to f \bar f H$, where $f$ is any light…
We examine two processes, the neutrino production process e^+e^- ---> N\nu and the inverse neutrinoless double-beta decay process e^-e^- --->W^-W^- as possible places for discovering heavy neutrinos in future lepton linear colliders. The…
It is shown that a certain angular asymmetry of charged leptons produced in the decay of $Z$ in the process $e^+e^- \to ZH$, related to a tensor polarization component of the $Z$, can be used to constrain the anomalous triple-Higgs…
We discuss the potential of NLC500 and NLC1000 to probe Z-Z' mixing and mass by the reaction e^+e^- -> W^+W^- with longitudinally polarized electrons. We perform a model-independent analysis of the deviations from the Standard Model, and…
Extra neutral gauge bosons arise in many extensions of the Standard Model. If one were to be discovered it would be necessary to measure its properties so that we could understand its origins. In this report we find that Z' couplings can be…
The sensitivity to the $Z^\prime$ 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 are studied. To this…
We explore the use of polarized $e^+/e^-$ beams and/or the information on final state decay lepton polarizations in probing the interaction of the Higgs boson with a pair of vector bosons. A model independent analysis of the process $e^+…
Many types of new physics can lead to contact interaction-like modifications in $e^+e^-$ processes below direct production threshold. We examine the possibility of uniquely identifying the effects of graviton exchange from amongst this…
A charged Higgs pair can be produced at an ee collider through a t-channel exchange of a heavy neutrino (N) via e^+ e^- -> H^+ H^- and, if N is a Majorana particle, also via the lepton number violating (LNV) like-sign reaction e^\pm e^\pm…
We study the process $e^- + e^+ \to e^+ + e^+ + e^- + e^-$ for ILC and CLIC energy regimes, in the minimal 3-3-1 model framework. The main contributions, for the production of two bileptons each one decaying into two same-sign leptons, come…
We investigate possibilities for detecting heavy Majorana neutrinos ($N$'s) in $e^+e^-$ at LEP200 and future Linear Colliders. We concentrate on the processes where the pairs of intermediate heavy $N$'s produce a clear signal of total…
Many types of new physics can lead to contact interaction-like modifications in e^+ e^- processes below direct production threshold. We examine the possibility of uniquely identifying the effects of graviton exchange, which are anticipated…
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…