Related papers: Electroweak Limits on Non-Universal Z' Bosons
It is well known that technicolor models in which the electroweak symmetry is broken by QCD-like strong dynamics at the TeV scale generally predict unacceptably large corrections to low-energy observables. We investigate the models of…
We study the impact of additional beyond-the-Standard Model (BSM) fermions, charged under the Standard Model (SM) $SU(2)_L \otimes U(1)_Y$ gauge group, on the electroweak phase transition (EWPT) in a 2-Higgs-Doublet-Model (2HDM) of type II.…
This is a short review of present and future limits on new neutral gauge bosons, in particular on hadrophilic or leptophobic $Z'$s recently proposed to interpret the observed fluctuations of $\Gamma _{c,b}$ at LEP. Light gauge bosons…
Gauged extensions [$SU(2)_L\otimes U(1)_Y\otimes U(1)_X$] of the standard $SU(2)_L\otimes U(1)_Y$ model obtained without extending the fermion content of the model are studied. Models that are possible when $U(1)_X$ is identified with some…
I investigate the phenomenology of supersymmetric models with extra vector-like supermultiplets that couple to the Standard Model gauge fields and transform as the fundamental representation of a new confining non-Abelian gauge interaction.…
We investigate a supersymmetric theory with an extra U(1) gauge symmetry surviving down to low energies. The extra U(1) is assumed to originate from an E$_6$ grand unified theory (GUT). We show that if one assumes universal soft…
We consider a Standard Model extension by a heavy charged scalar gauged only under the $U_{Y}(1)$ weak hypercharge gauge group. Such an extension, being gauge invariant with respect to the SM gauge group, is a simple special case of the…
Most neutrino mass extensions of the standard electroweak model entail non-standard interactions which, in the low energy limit, can be parametrized in term of effective four-fermion operators $\nu_\alpha \nu_\beta \bar f f $. Typically of…
We define a new class of Z' models with neutral flavour-changing interactions at tree level in the down-quark sector. They are related in an exact way to elements of the quark mixing matrix due to an underlying flavoured U(1)' gauge…
A flavor-universal extension of the strong interactions was recently proposed in response to the apparent excess of high-$E_T$ jets in the inclusive jet spectrum measured at the Tevatron. The color octet of massive gauge bosons (`colorons')…
The ATLAS collaboration reported excesses at around 2 TeV in the di-boson production decaying into hadronic final states. We consider the possibility of explaining the excesses with extra gauge bosons in two simple non-Abelian extensions of…
It has been shown recently that the triple neutral gauge boson couplings are not uniquely determined in noncommutative extension of the Standard Model (NCSM). Depending on specific schemes used, the couplings are different and may even be…
Motivated by flavor non-universality and anomalies in semi-leptonic B-meson decays, we present a general and systematic discussion about how to construct anomaly-free $U(1)'$ gauge theories based on an extended standard model with only…
We derive limits on a class of new physics effects that are naturally present in grand unified theories based on extended gauge groups, and in particular in $E_6$ and $SO(10)$ models. We concentrate on $i$) the effects of the mixing of new…
We present a family-non-universal extension of the Standard Model where the the first two families feature both quark-lepton and electroweak-flavour unification, via the $SU(4) \times Sp(4)_L \times Sp(4)_R$ gauge group, whereas…
The problem of possible deviations from the Standard Model is considered in the framework of a variant of dynamical electroweak symmetry breaking. It comes clear, that the parameters of the theory, being obtained earlier and describing…
In this paper we do an analysis of the reaction $e^+e^-\to W^+W^-$ for various options of the Next Linear Colliders (NLC), by considering the possibility of deviations from the Standard Model induced by anomalous trilinear vector boson…
The phenomenology of an additional U(1) neutral gauge boson Z' coupled to the third family of fermions is discussed. One might expect such a particle to contribute to processes where taus, b and t quarks are produced. Precision data from…
The $\eegg$ event reported recently by the CDF Collaboration has been interpreted as a signal of supersymmetry in several recent papers. In this article, we report on an alternative non-supersymmetric interpretation of the event using an…
We construct UV-complete models for non-standard neutrino interactions mediated by a sub-GeV gauge boson Z' coupled to baryon number $B$ or $B-L$. A flavor-dependent Z' coupling to neutrinos is induced by mixing a U(1)'-charged Dirac…