Related papers: New heavy charged leptons at future high energy el…
The production and decay of exotic leptons are discussed in the context of the vector singlet, vector doublet and fer\-mion mirror-fer\-mion models, at c.m. energies $\sqrt{s}=190GeV$ (LEP II) and $\sqrt{s}=500GeV$ (NLC). The model…
We investigate the single and pair production of new heavy leptons via string inspired $E_{6}$ model at future linear colliders. Signal and corresponding backgrounds for these leptons are studied. We have found that single production of…
We discuss the production, at high--energy e$^+$e$^-$ linear colliders, of new heavy fermions predicted by extensions of the Standard Model. We analyze in great details the various signals and the corresponding backgrounds for both pair…
We study the production and decay of fourth generation leptons at the Large Hadron Collider (LHC).We find that for charged leptons with masses under a few hundred GeV, the dominant collider signal comes from the production through a W-boson…
Doubly charged excited leptons give rise to interesting signatures for physics beyond the standard model at the present Large Hadron Collider. These exotic states are introduced in extended isospin multiplets which couple to the ordinary…
We analyse the signal sensitivity of multi-lepton final states at collider that can arise from doubly and singly charged Higgs decay in a type-II seesaw framework. We assume triplet vev to be very small and degenerate masses for both the…
We discuss the production of heavy leptons at a future high--energy $e^+e^-$ linear collider with a center of mass energy of 500 GeV. Signals and backgrounds are analyzed for their single production in association with ordinary leptons.…
A search for vector-like leptons in multilepton final states is presented. The data sample corresponds to an integrated luminosity of 77.4 fb$^{-1}$ of proton-proton collisions at a center-of-mass energy of 13 TeV collected by the CMS…
Given the current absence of new physics signals at the LHC, it is increasingly important to investigate alternative scenarios beyond those commonly explored. In this work, we study a variant of the 331 model that predicts the existence of…
We study the production and decay of heavy selectrons in the electron-photon mode of a linear collider of the next generation. The standard model backgrounds can be substantially reduced by appropriate kinematical cuts. As a consequence,…
We investigate the production of fourth generation neutrino in the context of new $e \nu_4 W$ magnetic dipole moment type interaction in $ep$ collisions at the future lepton-hadron colliders. We have obtained the mass limits of 700 GeV for…
We study the diagnostic power of future $e^+e^-$ colliders with ${\sqrt {s}} = 500$ GeV (the New Large Collider ($NLC$)) for a model independent determination of the $Z'$ gauge couplings to quarks and leptons. The interference of the $Z'$…
Vectorlike leptons are an intriguing possibility for physics beyond the Standard Model. We study the reach for discovering (at 5$\sigma$ significance) or excluding (at 95 per cent confidence) models of charged vectorlike leptons that mix…
We discuss the possibility of detecting heavy spin-3/2 leptons at LEP2 and NLC energies. The angular distributions of primary ordinary leptons are shown to be a good measure to discriminate between a heavy spin-3/2 lepton and a similar…
A search for charged leptons with large impact parameters using 139 fb$^{-1}$ of $\sqrt{s} = 13$ TeV $pp$ collision data from the ATLAS detector at the LHC is presented, addressing a long-standing gap in coverage of possible new physics…
An electron-positron linear collider in the energy range between 500 and 1000 GeV is of crucial importance to precisely test the Standard Model and to explore the physics beyond it. The physics program is complementary to that of the Large…
This work explores the discovery potential of the first-generation weak isosinglet Vector-Like Leptons (VLLs), denoted by $E^\pm$, via pair production at future electron-positron colliders. Our analysis adopts a comprehensive framework that…
This Letter describes the search for an enhanced production rate of events with a charged lepton and a neutrino in high-energy pp collisions at the LHC. The analysis uses data collected with the CMS detector, with an integrated luminosity…
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…
In the vector condensate model a doublet of vector fields plays the role of the Higgs doublet of standard model and the gauge symmetry is broken dynamically. This results in a theory surviving the test of radiative corrections provided the…