Related papers: Leptoquark Production in Electron-Photon Scatterin…
The study of top-quark properties will be a central aspect of the physics programme of any future lepton collider. In this article, we investigate the production of top-quark pairs in the semi-leptonic decay channel in $\rm e^+e^-$…
The next generation of $e^+e^-$-colliders will offer a possibility of clean testing of QCD dynamics in the Regge limit. Recent progress in the theoretical description of exclusive processes permits for many of them a consistent use of the…
We discuss the coherent photo- and leptoproduction of vector mesons from deuterium at intermediate (virtual) photon energies, 3 GeV < nu < 30 GeV. These processes provide several options to explore the space-time evolution of small size…
$\gamma\gamma\to\gamma Z$ scattering at the Photon Linear Collider is considered. Explicit formulas for helicity amplitudes due to $W$ boson loops are presented. It is shown that the $Z\gamma$ pair production will be easily observable at…
We study the top-quark pair production via polarized and unpolarized photon collisions at the International Linear Collider in the context of the littlest Higgs model with T-parity. We calculate the production cross section of the process…
I give an overview of the ability of a high energy $\mu^+\mu^-$ collider to discover new particles and interactions. I start with heavy fermions which will be the most straightforward to produce and observe. I then discuss single leptoquark…
Leptoquarks are known to generate a wide range of potentially observable phenomena, and have been searched for in different experiments. We show that the observed baryon asymmetry and neutrino mass scale can both be simultaneously produced…
Data from the Large Electron Positron collider (LEP) at CERN on hadron production in gamma-gamma interactions exceed the predictions of the standard model by an order of magnitude at the highest observed transverse momenta in three…
We analyze the production in $e^+e^-$ collisions of new heavy fermions stemming from extensions of the Standard Model. We write down the most general expression for the production of two heavy fermions and their subsequent decays, allowing…
Observing multiphoton electron-positron pair production (the nonlinear Breit-Wheeler process) requires high-energy $\gamma$ rays to interact with strong electromagnetic fields. In order for these observations to be as precise as possible,…
We study slepton pair-production in polarized $\gamma\gamma$ scattering. It turns out that the combined use of polarization and angular correlations greatly enhances the resolving power of this reaction.
At high energy, the photoproduction or electroproduction of Vector Mesons allow to prepare a beam of quark-antiquark pairs of a given flavor. At high momentum transfer, the study of the scattering of these pairs on a nucleon opens up an…
Heavy quark productions in high energy polarized scatterings are reviewed from a personal point of view. After mentioning why heavy quark physics is so interesting, I concentrate on two rather specific subjects: (1) polarized…
One of the important features of the littlest Higgs model with T-parity, called the $LHT$ model, is that it introduces the mirror fermions, which are the T-parity partners of the standard model fermions. In this paper, we discuss production…
We discuss the production of the doubly charged leptons in future linear electron positron colliders, such as the International Linear Collider and Compact Linear Collider. Such states are introduced in extended weak-isospin multiplets by…
A high energy $e^+e^-$ linear collider (NLC) is an excellent tool for studying the properties of the top quark. In this talk I review some of the theory of top quark production and decay in $e^+e^-$ collisions both at threshold and in the…
We describe how to probe new physics through examination of the form factors describing the Ztt couplings via the scattering process e^-e^+->t+tbar. We focus on experimental methods on how the top quark momentum can be determined and show…
A search is presented for a singly produced third-generation scalar leptoquark decaying to a $\tau$ lepton and a bottom quark. Associated production of a leptoquark and a $\tau$ lepton is considered, leading to a final state with a bottom…
Angular and energy distributions for leptons and bottom quarks in the process e^+e^- --> t t-bar --> l^{+-}/b(b-bar) ... have been calculated assuming the most general top-quark couplings. The double distributions depend both on…
For the first time, the production of a massive dark photon (DP) in the $\gamma e^-$ scattering at the future lepton colliders ILC, CLIC, and CEPC is examined. The invisible decay mode of the DP is addressed. We have studied both the…