Related papers: Observing the technieta at a photon linear collide…
Topcolor--assisted technicolor provides a dynamical explanation for electroweak and flavor symmetry breaking and for the large mass of the top quark without unnatural fine tuning. A major challenge is to generate the observed mixing between…
We briefly review the recent developments of probing the electroweak symmetry breaking mechanism at high energy colliders such as the CERN LEP2, the Fermilab Tevatron, the CERN LHC and the e(+)e(-) linear colliders. Both weakly interacting…
We study the production of composite scalar leptoquarks in $e\gamma$ colliders, and we show that an $e^+e^-$ machine operating in its $e\gamma$ mode is the best way to look for these particles in $e^+e^-$ collisions, due to the hadronic…
We consider the detection of the technirho in technicolor models that include a weak scalar doublet. In these models, the scalar develops a vacuum expectation value when the technifermions condense, and fermion masses are generated through…
It is very likely that in 3-4 years the construction of one or two linear colliders with c.m.s energy up to 0.5--1.5 TeV will be started. Besides e^+e^- collisions, linear colliders give a unique possibility to study gamma-gamma and…
The interactions of electroweak gauge bosons are severely constrained by the symmetries inferred from low energy observables. The exploration of the dynamics of electroweak symmetry breaking requires therefore both an experimental…
We describe the anticipated experimental program of an e+e- linear collider in the energy range 500 GeV -- 1.5 TeV. We begin with a description of current collider designs and the expected experimental environment. We then discuss precision…
We investigate the sensitivity to the effective operators describing interactions between dark matter particles and photons at future high energy $e^+e^-$ colliders via the $\gamma+ \slashed{E}$ channel. Such operators could be useful to…
High energy photon colliders (gamma-gamma, gamma-electron) based on backward Compton scattering of laser light is a very natural addition to e+e- linear colliders. In this report we consider this option for the TESLA project. Recent study…
We discuss whether the enhancement in the diphoton final state at $M_{\gamma \gamma}$ = 750 GeV, observed recently by the ATLAS and CMS Collaborations could be a neutral pseudoscalar technipion $\tilde{\pi}^0$. We considered two distinct…
We propose a scenario in which the electroweak symmetry is spontaneously broken by an $SU(4)$ technicolor gauge interaction which also manages to break itself completely. The technicolor gauge bosons and technifermions are not confined by…
In multiscale and topcolor-assisted models of walking technicolor, relatively light spin-one technihadrons $\rho_T$ and $\omega_T$ exist and are expected to decay as $\rho_T \to W \pi_T, Z \pi_T$ and $\omega_T \to \gamma \pi_T$. For…
The particle production in photon-photon ($\gamma \gamma$) interactions present in electron-ion collisions is investigated. We present calculations for the total cross sections and event rates related to the production of light mesons…
A search for the pseudoscalar meson eta_b is performed in two-photon interactions at LEP~2 with an integrated luminosity of 699 pb^-1 collected at e+e- centre-of-mass energies from 181 GeV to 209 GeV. One candidate event is found in the…
In absence of the Standard Model Higgs boson the interaction among the gauge bosons becomes strong at high energies and influences the couplings between them. Each trilinear and quartic gauge boson vertex is characterised by a set of…
We report the first measurement of the differential cross section for the process gamma gamma --> eta eta in the kinematic range above the eta eta threshold, 1.096 GeV < W < 3.8 GeV over nearly the entire solid angle range, |cos theta*| <=…
This small review is devoted to $\gamma\gamma$ collisions including methods of creating the colliding $\gamma \gamma$ beams of high energy and physical problems which can be solved or clarified in such collisions. Contents: 1. Introduction…
One of the main goals of future electron-ion colliders is to improve our understanding of the structure of hadrons. In this letter, we study the exclusive $\eta_c$ production by $\gamma^{*} \gamma$ interactions in $eA$ collisions and…
We study in a model independent way the role of a techniomega resonance in the process e^+ e^- --> W^+ W^- Z at the Next Linear Collider.
We present new results obtained from a series of follow-up e+e- coincidence measurements in heavy-ion collisions, utilizing an improved experimental set-up at the double-Orange beta-spectrometer of GSI. The collision system U+Ta was…