Related papers: Lepton Spectra from e^+ e^- \to W^+ W^- in the BES…
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 search for the doubly charged leptons ($L^{--}$) predicted in composite models including extended weak isospin multiplets namely, $I_{W}=1$ and $I_{W}=3/2$ at the Future Circular Collider (FCC)-based energy-frontier electron-proton…
The process e+e- --> W+W- provides a valuable laboratory to test the Standard Model (SM) and to search for new physics. The most general helicity amplitudes for this process require the introduction of nine form-factors which we calculate…
We evaluate the constraints on anomalous trilinear gauge-boson couplings that can be obtained from the study of electron-positron annihilation into $W$ pairs at a facility with either the electron beam longitudinally polarized or both…
Many new physics models predict the existence of TeV-scale charged gauge boson $W^\prime$ together with Higgs boson(s). We study the $W^\prime WH$ interaction and explore the angular distribution of charged lepton to distinguish $W_R^\prime…
The neural network approach is applied to search for the Z'-boson within the LEP2 data set for e+ e- -> e+ e- scattering process. In the course of the analysis, the data set is reduced by 20 percent. The axial-vector and vector couplings of…
Single $W$-boson production in $e^-\gamma$ collisions with polarized beams is investigated. In the framework of the Standard Model the updated estimates for the measurement precision of photon anomalous coupling parameters $ \kappa_{…
The fact that the measured B to \pi \pi, \pi K branching ratios exhibit puzzling patterns has received a lot of attention in the literature and motivated the formulation of a series of new physics scenarios with enhanced Z-penguins. In this…
We compute the energy spectrum of charged leptons in the decay $H^+\to \bar b+(t\to bl\nu_l)$. The shape of the lepton spectrum obtained, and also the mean lepton energy, are sensitive to the handedness of the intermediate top quark. This…
Cross-section and angular distributions for hadronic and lepton-pair final states in e+e- collisions at centre-of-mass energies between 189 GeV and 209 GeV, measured with the OPAL detector at LEP, are presented and compared with the…
The mass and width of the W boson are measured using e+e- -> W+W- events from the data sample collected by the OPAL experiment at LEP at centre-of-mass energies between 170 GeV and 209 GeV. The mass (mw) and width (gw) are determined using…
The exclusive (B -> K_2 l^+ l^-) decay is studied using the most general, model independent four-fermion interaction. The sensitivity of the ratio of the decay widths when K_2 meson is longitudinally and transversally polarized, the…
The main possibilities of investigation of leptons and bosons birth in interaction of polarized photons are considered. The usage of $\gamma \gamma \to f \bar{f} [+\gamma]$ reactions for the luminosity measurement on linear photon collider…
It is shown that the difference in the distributions of positive ($\mu^+$) and negative charged leptons ($\mu^-$) in reactions $\gamma \gamma \to \mu^+\mu^-+\nu\bar\nu$ and $\gamma \gamma \to W^\pm\mu^\mp +\nu(\bar\nu)$ at $\sqrt{s}>200$…
We discuss the process $\ell^+\ell^- \to N W^{\pm} \ell^{\mp}$, where $N$ is a heavy Majorana neutrino and $\ell = e, \mu$. Large cross sections are expected for these processes at high center-of-mass energies, which can be reached at…
On the basis of the so-called supersymmetric yukawaon model, it is investigated what form of the superpotential W can lead to the observed charged lepton mass spectrum. A simple form of W can speculate reasonable values of K(\mu)=(m_e…
W+W-gamma production at LEP2 is studied using data collected with the DELPHI detector at centre-of-mass energies between 189 GeV and 209 GeV, corresponding to an integrated luminosity of about 600 pb^-1. Cross-sections are measured for the…
The contributions of $s-$channel Higgs in $l^+ l^- \rightarrow q \bar{q}$ processes in the general lepton collider ($l^+ l^-$ collider) within Standard Model is studied. A new idea to extract the contribution by using the data from both…
We reexamine lepton mixing in gauge models by considering two theories within the type I seesaw mechanism, the Extended Standard Model, i.e. SU(2)_L \times U(1)_Y with singlet right-handed heavy neutrinos, and the Left-Right Model SU(2)_L x…
Lepton number violating (LNV) $A(e^-,e^+)X$ double charge exchange (LDCE) reactions on nuclei at accelerator facilities with multi-GeV beams are proposed as a probe for physics beyond the Standard Model (BSM). A second order formalism is…