Related papers: $\sigma^{tot}_{ee \gamma \gamma}$ at $e^+e^-$ coll…
We discuss the possibility of observing doubly charged Higgs bosons in $\gamma \gamma$ collisions. We find that one can increase the range of observability close to the kinematic limit by a judicious choice of the polarisations of the…
Important analyses at a future linear collider, including top-quark and W-boson mass measurements will depend upon the precise determination of the luminosity spectrum. This can be done, in principle,in the planned detectors. We review the…
The reaction e+ e- -> e+ e- gamma* gamma* -> e+ e- hadrons is analysed for quasi-real virtual photons using data collected by the L3 detector during the LEP high energy runs at sqrt(s) = 183 and 189 GeV. Preliminary results on the cross…
Single top quark cross section evaluations for the complete sets of tree-level diagrams in the $e^+ e^-$, $e^- e^-$, $\gamma e$ and $\gamma \gamma$ modes of the next linear collider with unpolarized and polarized beams are performed within…
I summarize the prospects for discovering and studying the properties of Higgs particles at future high-energy and high-luminosity $e^+e^-$ linear colliders. I will focus on the Higgs particle of the Standard Model and the Higgs bosons…
We present a new Monte-Carlo generator, {\tt ee$\in$MC}, for the simulation of $e^{+}e^{-} \to \mu^{+} \mu^{-} (\gamma) $, $e^{+}e^{-} \to \tau^{+}\tau^{-} (\gamma) $ and $\tau$ lepton decays which is suitable for $e^{+}e^{-}$ colliders…
We investigate the polarized photon structure functions $g_1^\gamma$ and $g_2^\gamma$ which can be studied in the future polarized version of ep or e$^+$e$^-$ colliders. The NLO QCD calculations of $g_1^\gamma$ and the possible twist-3…
The deviation between the standard model prediction and the measurement of the muon g-2 is currently at 3-4 sigma (can be up to 7 sigma in the upcoming experiment E989). If new physics is responsible for such discrepancy, it is expected…
The effect of the overlap of gamma gamma -> hadrons to H nu nu events has been studied for the case of the Tesla e+e- linear collider at 350 GeV. It was found that, due to the significant bunch length and the track extrapolation accuracy…
Options for future lp, lA, gamma-p, gamma-A and FEL gamma-A colliders are discussed
Parity violating left-right scattering asymmetries at future high energy e+e- and e-e- colliders are examined. The utility of two polarized beams for precision measurements is pointed out. Sensitivity to ``new'' short-distance physics is…
The production of massive quarks and leptons in $e^+e^-$ collisions is studied using exact helicity amplitudes. Total cross sections as a function of $y_{\rm cut}$, in both the JADE and the $k_T$ algorithms, are presented and compared with…
We study and compare the discovery potential for heavy neutral gauge bosons ($Z'$) at various $e^+e^-$ and $p\stackrel{(-)}{p}$ colliders that are planned or have been proposed. Typical discovery limits are for the TEVATRON $\sim 1$ TeV,…
We perform a model independent analysis of the production of scalar and vector leptoquarks in the $e^-\gamma$ mode of a linear collider of the next generation. Since these leptoquarks are produced singly, higher masses can be probed than in…
Theoretical backgound for bileptonic gauge bosons is reviewed, both the SU(15) GUT model and the 3-3-1 model. Then the mass limits for bileptons are discussed coming from $e^+e^-$ scattering, polarized muon decay and muonium-antimuonium…
The search for a Z' is one of the tasks of future colliders. I study the capability to detect the Z' at a linear e+e- collider operating below resonance production. Depending on m_{\Zp} and the collider parameters we will be able to…
The loop induced coupling of an intermediate mass Higgs boson to two photons is a sensitive and unique measure for precision tests of physics beyond the Standard Model. In this work we summarize recent results on the expected precision of…
We generalize our previous model for $\gamma^* p$ scattering to $\gamma \gamma$ scattering. In the latter case the number of components naturally grows. When using the model parameters from our previous $\gamma^* p$ analysis the model cross…
``All future $e^+e^-$ Higgs factories have similar reach for the precise measurement of the Higgs boson properties.'': this popular statement has often led to the impression that all $\rm e^+e^-$ options are scientifically equivalent when…
Production of a single doubly charged Higgs boson $Delta^{--}$ in polarized $e^+e^-$ and $e^+\gamma$ collision modes of the linear collider have been investigated. The mass range of $Delta^{--}$ to be probed extends up to the collision…