Related papers: Unique heavy lepton signature at $e^+e^-$ linear c…
We consider the possibility of observing deviations from the Standard Model gauge-boson self-couplings at a future $500$~GeV $e^+ e^-$ linear collider. We concentrate on the case in which the electroweak symmetry breaking sector is strongly…
We consider possible production of heavy leptons via anomalous interactions at future $ep$ colliders (THERA and LHeC), $e^+e^-$ colliders (ILC and CLIC) and $pp$ collider CERN LHC. The production, backgrounds and signatures of heavy leptons…
It is shown that in a large class of E(6) models, either an e+e- collider operating at $\rs \geq 1.5$ TeV must find a signal for the production of exotic leptons, or a collider operating at $\rs \geq 300$ GeV must find at least one light…
We analyze the influence of anomalous gauge couplings in the reaction $e^- \: e^- \longrightarrow e^- \: W^- \: \nu_e$ at a 500 GeV linear collider. The limits imposed by this process on deviations from the standard model of electro-weak…
We present the first study of the production of a Standard Model Higgs boson at a lepton collider in association with a pair of W bosons, $e^+_{} e^-_{} \to W^+_{} W^-_{} H$, in the inverse seesaw model. Taking into account all relevant…
Heavy neutral gauge bosons, Z's, are predicted by many theoretical schemes of physics beyond the Standard Model, and intensive searches for their signatures will be performed at present and future high energy colliders. It is quite possible…
Many extensions of the standard model predict the existence of extra neutral vector bosons, generically referred as $Z^\prime$. This boson may be discovered at the LHC but in this case it will be necessary to study the respective parameters…
The lepton number violating process, $e^- e^- \to W^- W^-$ has been widely discussed in the Majorana neutrino exchange mechanism. Here, we discuss this process in a composite neutrino model where excited Majorana neutrinos are exchanged. We…
We investigate the production, signatures and backgrounds of a pair of heavy-exotic charged leptons and a heavy-exotic neutrino together with the exotic charged lepton in the framework of the vector singlet model, vector doublet model, and…
In $e^+ e^-$ collisions, electromagnetic effects caused by large charge density bunches modify the effective acceptance of the luminometer system of the experiments. These effects consequently bias the luminosity measurement from the rate…
We present recent developments in the diagnostic study of heavy gauge bosons at future $pp$ (CERN LHC) and $e^+e^-$ (NLC) colliders with the emphasis on the model independent determination of gauge couplings of $Z'$ to quarks and leptons.…
The production at the LHC of exotic excited leptons of charge $Q = +2e$ is considered. Such states are predicted in composite models with extended isospin multiplets ($I_{W}=1$ and $I_{W}=3/2$). The coupling among these doubly charged…
We explore the discovery prospect of a very heavy neutrino at the proposed $e^+e^-$ collider for two different c.m.energies $\sqrt{s}=1.4$ TeV and 3 TeV. We consider production of heavy neutrino via $s$ and $t$-channel processes, and its…
$Z$ production at an $e^+e^-$ collider, associated with production of other particles, can be an accurate source of information of details of electroweak interactions, including possible interactions beyond the standard model. We discuss…
We point out that in a large class of superstring--inspired $E(6)$ models, either an e+e- collider operating at a center--of--mass energy $\rs= 1.5$ TeV or higher must detect the pair production of charged or neutral exotic leptons, or an…
Numerous non-standard dynamics are described by contact-like effective interactions that can manifest themselves through deviations of the cross sections from the Standard Model predictions. If one such deviation were observed, one should…
We study the possibilities to detect Majorana neutrinos in $e^- \gamma$ colliders for different center of mass energies. We study the $W^- W^- l_j^{+}(l_j^+\equiv e^+ ,\mu^+ ,\tau^+)$ final state which are, due to leptonic number violation,…
Model independent constraints on the mass of extra neutral gauge bosons and their couplings to charged leptons are given for LEP~II and a 500\,GeV $e^+e^-$ collider. Analytical exclusion limits are derived in the Born approximation. The…
We study the possibility of fingerprinting a strongly interacting $W$ boson sector which is consistent with present day LHC searches at the ILC with longitudinal as well as transversely polarized electron and positron beams. We account for…
We discuss three promising diagnostic probes of the couplings of a possible heavy $Z'$ boson at hadron colliders: the forward-backward asymmetry into leptons, the rare decay $Z' \ra W^{\pm} \ell^{\mp} \nu$, and associated production $pp \ra…