Related papers: Fermion pair production at $e^- e^+$ linear collid…
We discuss the sensitivity to four-fermion contact interactions of the process of fermion-pair production at the e^+ - e^- Linear Collider (LC), with E_{CM}=0.5 TeV and longitudinally polarized electron beam. The analysis is based on…
In its second phase, LEP has given the unique opportunity to study four fermion processes never observed before. This papers deals with a preliminary study of $WW$, $We\nu$, $ZZ$ and $Z\gamma^\star$ production in $e^+e^-$ collisions.…
In a five-dimensional model with one Universal Extra Dimension (UED), signals for a pair of n = 1 Kaluza-Klein excitations could be easily observed at a future e+ e- collider if the process in question is kinematically allowed. However,…
Model independent constraints on the mass of extra neutral gauge bosons and their couplings to charged leptons are given for LEP~II and a 500\,GeV $e^+e^-$ collider. Analytical exclusion limits are derived in the Born approximation. The…
Higgs pair production provides a unique handle for measuring the strength of Higgs self interaction and constraining the shape of the Higgs potential. Including radiative corrections to the trilinear couplings of $CP$-even Higgs, we…
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…
Unequal strengths of boundary localised terms lead to non-conservation of the Kaluza-Klein (KK) parity in the 4 + 1 Universal Extra Dimensional model. Consequently the first excited KK-partners of Standard Model particles are not stable by…
The production of charged kaon pairs in ultraperipheral heavy-ion collisions can proceed via photoproduction (gamma-Pomeron interaction) or via photon-photon fusion. An important contribution to this process arises from the decays of…
The electroweak phase transition in GUT inspired $SO(5)\times U(1) \times SU(3)$ gauge-Higgs unification is shown to be weakly first order and occurs at $T = T_c^{\rm EW} \sim 163\,$GeV, which is very similar to the behavior in the standard…
In the past year, a new non-supersymmetric framework for electroweak symmetry breaking (with or without Higgs) involving SU(2)_L * SU(2)_R * U(1)_{B-L} in higher dimensional warped geometry has been suggested. In this work, we embed this…
In Randall-Sundrum models, the Kaluza-Klein (KK) excitations of the gluon, g_{KK} have enhanced couplings to the right-handed quarks. In the absence of a gg g_{KK} coupling in these models, the single production of a g_{KK} from an initial…
We consider a minimal renormalizable non-supersymmetric $E_6$ Grand Unified Theory using fundamental representation $27$ for fermions and scalars. The scalar with adjoint representation ${78}$ is also taken for direct breaking of $E_{6}$ to…
We study the production of the lightest neutralinos in the radiative process $e^+e^- \to \tilde\chi^0_1 \tilde\chi^0_1\gamma$ in supersymmetric models with grand unification. We consider models wherein the standard model gauge group…
The search for charged Higgs bosons, which are predicted in supersymmetric theories, is difficult at hadron colliders if the mass is large. In this paper we present the theoretical set-up for the production of charged Higgs boson pairs at…
The exclusive production of one $\mu^+\mu^-$ pair in collisions of two ultra-relativistic nuclei is considered. We present the simple method for calculation of the Born cross section for this process. Then we found that the Coulomb…
Cross-sections for hadronic, b-bbar and lepton pair final states in e+e- collisions at sqrt(s) = 183 GeV, measured with the OPAL detector at LEP, are presented and compared with the predictions of the Standard Model. Forward-backward…
Universal extra dimensions and supersymmetry have rather similar experimental signatures at hadron colliders. The proper interpretation of an LHC discovery in either case may therefore require further data from a lepton collider. In this…
We study the one-loop radiative corrections to pair production of the supersymmetric scalar partners of the standard fermions in e+e- annihilation. Both electroweak and SUSY-QCD corrections are considered. Applications are for production of…
In a supersymmetric large extra dimension scenario, the production of Kaluza-Klein gravitinos accompanied by a photino at e^+ e^- colliders is studied. We assume that a bulk supersymmetry is softly broken on our brane such that the…
In the Two-Higgs-Doublet Model(2HDM) with large extra dimensions(LED), we study the contributions of virtual Kaluza-Klein(KK) gravitons to 2HDM charged Higgs production, especially in the two important production processes $e^+e^-\to…