Related papers: Precision Electroweak Constraints on Top-Color Ass…
We compute the leading corrections to the properties of W and Z bosons induced at the one-loop level in the SU(5)/SO(5) Littlest Higgs model with T parity, and perform a global fit to precision electroweak data to determine the constraints…
Assuming a heavy electroweak singlet scalar, which couples to the Standard Model gauge bosons only through loop-induced couplings, SU(2)_L x U(1)_Y gauge invariance imposes interesting patterns on its decays into electroweak gauge bosons,…
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 discuss electroweak precision constraints on dimension-6 operators in the effective theory beyond the standard model. We identify the combinations of these operators that are constrained by the pole observables (the W and Z masses and…
LHC searches for the standard model Higgs Boson in di-photon or di-tau decay modes place strong constraints on the light top-pion state predicted in technicolor models that include colored technifermions. Compared with the standard Higgs…
We obtain a new bound on the value of Peskin-Takeuchi S parameter in a wide class of bottom-up holographic models for technicolor. Namely, we show that weakly coupled holographic description in these models implies S>>0.2. Our bound is in…
We perform the fit of electroweak precision observables within the Standard Model with a 126 GeV Higgs boson, compare the results with the theoretical predictions and discuss the impact of recent experimental and theoretical improvements.…
This note presents constraints on Standard Model parameters using published and preliminary precision electroweak results measured at the electron-positron colliders LEP and SLC. The results are compared with precise electroweak…
We consider a gauge extension of the electroweak sector of the Standard Model based on the group G_2 x SU(2)x U(1). The exceptional group G_2 is the smallest rank two group that contains SU(3) as a subgroup; the SU(3) prediction sin^2…
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 ${\l}$…
Future high energy linear electron positron colliders with centre-of-mass enegies between 90 and 1000 GeV offer a unique opportunity to study precisely the Standard Model and phenomena from new physics. Most important, the mechanism of…
We survey the phenomenological constraints on abelian gauge bosons having masses in the MeV to multi-GeV mass range (using precision electroweak measurements, neutrino-electron and neutrino-nucleon scattering, electron and muon anomalous…
Precision electroweak data, a light higgs and LHC searches for new spin one particles are all very constraining on technicolor models. We use a holographic model of walking techicolor (WTC) gauge dynamics, tuned to produce a light higgs and…
We present the one-loop correction to the $W$ boson mass in U(1)$_z$ type extensions of the standard model. We compare it to an approximation, often used in high energy physics tools. We point out that if the $Z'$ boson -- predicted in…
A realistic technicolor model is presented with the dynamics below $150$ TeV treated explicitly. Electroweak symmetry is broken by the condensates of a `minimal' doublet of technifermions. The new feature of the model is that the the third…
We investigate radiative corrections to electroweak precision observables, specifically the Peskin--Takeuchi parameters $\mathrm{S}$, $\mathrm{T}$, and $\mathrm{U}$, in the $SU(3)_C \times SU(3)_L \times U(1)_X$ (331) model with $\beta =…
Using Big Bang Nucleosynthesis limits on the number of light neutrinos we derive a cosmological lower bound of $\approx 2$ TeV on the scale of extended technicolor interactions (or any other new interactions) for the third family in models…
The renormalizable coloron model is the minimal extension of the standard model color sector, in which the color gauge group is enlarged to SU(3)_{1c} x SU(3)_{2c}. In this paper we discuss the constraints on this model derived from the…
A linear realization of a model of dynamical electroweak symmetry breaking describing additional heavy vector bosons is proposed. The model is a SU(2)_L x U(1) x SU(2)_L' x SU(2)_R' gauge theory, breaking at some high scale u to SU(2)_weak…
Overall, the Standard Model describes electroweak precision data rather well. There are however a few areas of tension (charged current universality, NuTeV, (g-2)_\mu, b quark asymmetries), which I review emphasizing recent theoretical and…