Related papers: Once more on extra quark-lepton generations and pr…
Precision electroweak physics can provide fertile ground for uncovering new physics beyond the Standard Model (SM). One area in which new physics can appear is in so-called "oblique corrections", i.e., next-to-leading order expansions of…
The ununified standard model is an extension of the standard model that contains separate electroweak gauge groups for quarks and leptons. When it was originally proposed, data allowed the new gauge bosons to be quite light. We use recent…
We study the effect of bulk fermions on electroweak precision observables in a recently proposed model with warped extra dimensions and no custodial symmetry. We find that the top-quark mass, together with the corrections to the Zbb vertex…
In this paper we express the effect of new physics on gauge boson self energy corrections through non-renormalizable dimension six operators. Using the precision electroweak data we then determine a lower bound on the scale ${\l}$…
The constraints on the mixing angles of the standard fermions with new heavy particles that can appear in many extensions of the electroweak theory are reviewed. Some emphasis is put in distinguishing the effects of a mixing with new states…
If there is new physics associated with the top quark, it could show up as anomalous couplings of the top quark to weak gauge bosons, such as $Z\ttbar$ and $W\tbbar$ vector and axial-vector couplings. We use the processes $\ttbar\to…
We derive the low-energy electroweak effective lagrangian for the case of additional heavy, unmixed, sequential fermions. Present data still allow for the presence of a new quark and/or lepton doublet with masses greater than $M_Z/2$,…
The lightest Higgs scalar boson mass in supersymmetry can be raised significantly by extra vector-like quark and lepton supermultiplets with large Yukawa couplings but dominantly electroweak-singlet masses. I consider models of this type…
The present status of precision electroweak data is reviewed. These data include measurements of e+e- -> f+fbar, taken at the Z resonance at LEP, which are used to determine the mass and width of the Z boson. In addition, measurements have…
Experiments at the LHC are sensitive to the presence or absence of matter quanta at mass scales far beyond the scales they can probe directly. The production of $Z$ boson pairs by gluon-gluon fusion is greatly enhanced if there are…
Although often quoted as a discovery collider, the LHC will also allow for precise measurements. In particular, in the electroweak sector, the determination of the masses of the top quark and the W boson will benefit from high statistics…
The electroweak theory has been tested to high precision, with measurements probing its predictions at the loop level. The current generation of particle accelerators will produce enough W and Z bosons through hadron collisions to…
Precise determinations of the masses of the $W$ boson and of the top quark could stringently test the radiative structure of the Standard Model (SM) or provide evidence for new physics. We analyze the excellent prospects at a muon collider…
Within the Constrained Minimal Supersymmetric Model (CMSSM) it is possible to predict the low energy gauge couplings and masses of the 3 generation particles from a few supergravity inspired parameters at the GUT scale. Moreover, the CMSSM…
A model for electroweak unification of quarks and leptons, in a gauge group $SU_{C}(3)\times SU(4)\times U_{X}(1)$ is constructed. The model requires, three generations of quarks and leptons which are replicas (mirror) of the standard…
We discuss upper limits on the electric dipole moments (EDM) of the tau-lepton, heavy quarks, and W-boson, which follow from the precision measurements of the electron and neutron EDM.
We show that the $m_W$ measurement is a direct probe of New Physics (NP) contributing to lepton and missing transverse momentum ($\ell+MET$), independently from indirect tests via the electroweak fit. Such NP modifies the kinematic…
We discuss extension of the electroweak gauge group to $SU(3)_L \times SU(3)_R \times U(1)_{XL} \times U(1)_{XR}$. This adds new leptons to the familiar 331-model. The explanation for three light quark-lepton families remains but new…
Effects of electroweak phase transition (EWPT) in balance between baryon excess and the excess of stable quarks of new generation is studied. With the conservation of SU(2) symmetry and other quantum numbers, it makes possible sphaleron…
SU(2)xU(1) electroweak gauge model without Higgs sector is extended by a new vector field C interacting with leptons and quarks of both chiralities. This interaction is treated under a dynamical assumption in a self-consistent…