Related papers: Nonoblique Effects and Weak-Isospin Breaking from …
In extended technicolor (ETC) theories, while the sideways ETC boson exchange decreases the width $\Gamma_b \equiv \Gamma (Z\rightarrow b \bar{b})$, the flavor-diagonal ETC boson exchange tends to increase it, and the ETC-corrected $R_b…
We study the effect of the diagonal extended technicolor(ETC) gauge boson on the oblique correction parameters. It is shown that in the $T$ parameter is unacceptably large when the $Zbb$ vertex correction and $S$ parameter are consistent…
Extended technicolor (ETC) theories typically require ETC gauge bosons lighter than of order 1 TeV, to perturbatively generate the $t$ quark mass. We point out that explicit models of $t-b$ mass splitting also typically contain additional…
We show that the flavor-diagonal gauge boson of the extended technicolor theory contributes with opposite sign to the standard model correction for the $Zbb$ vertex. This mechanism can naturally explain the deviation of the LEP result from…
We study radiative corrections on $Zb{\bar b}$ vertex generated by the ETC gauge bosons, ``diagonal'' as well as sideways. Although the oblique corrections due to the ETC bosons are small in comparison with the oblique correction due to the…
We explore corrections to electroweak parameters in the context of Extended Technicolor (ETC) models in which the ETC gauge-boson which generates the top-quark mass carries weak $SU(2)$ charge. For $m_t \sim 150$ GeV there exist potentially…
We estimate the correction to the Zbb-bar vertex arising from the exchanges of the sideways extended technicolor (ETC) boson and the flavor-diagonal ETC boson in the multiscale walking technicolor model. The obtained result is too large to…
The deviation of the experimental value of $R_b \equiv \Gamma_b/\Gamma_h$ from the standard-model prediction can be naturally explained in the extended technicolor scenario.The diagonal extended technicolor gauge boson which…
LEP precision measurements of the $Zb\bar{b}$ vertex coupling are sufficiently accurate to see the non-oblique corrections from the heavy gauge boson responsible for the large top mass in standard extended tecnicolour models. If the ETC…
Many types of physics beyond the standard model include an extended electroweak gauge group. If these extensions are associated with flavor symmetry breaking, the gauge interactions will not be flavor-universal. In this note we update the…
A massive gauge boson coupling to the third family but not lighter families mixes with the $Z$. The $Z$ partial width to $b\overline{b}$ increases, the $\tau$ asymmetry parameter increases, the invisible width of the $Z$ decreases, and…
Extended technicolor theories generate potentially large corrections to the $\Zbb$ vertex which can be observed in current experiments at LEP.
New strong gauge interactions remain a viable source for the electroweak symmetry breaking. However, addressing the generation of fermion masses remains a challenge. A basic observable which provides stringent constraints on the flavor…
We analyze the diagonal and transition magnetic and electric dipole moments of charged leptons in extended technicolor (ETC) models, taking account of the multiscale nature of the ETC gauge symmetry breaking, conformal (walking) behavior of…
We parameterize the non-universal couplings of t-t-Z and t-b-W in the electroweak chiral lagrangian approach, and examine the constraints on these parameters from the LEP data. We also study how the SLC, Tevatron, LHC and NLC can improve…
In topcolor-assisted technicolor models (TC2) the hitherto unconstrained lepton flavor mixing induced by the new gauge boson $Z'$ will lead to the lepton flavor violating productions of $\tau\bar \mu$, $\tau\bar e$ and $\mu\bar e$ in…
These two lectures on technicolor and extended technicolor (ETC) were presented at l'Ecole de GIF at LAPP, Annecy-le-Vieux, France, in September 2001. In Lecture I, the motivation and structure of this theory of dynamical breaking of…
We analyze the constraints on the the vacuum polarization of the standard model gauge bosons from a minimal set of flavor observables valid for a general class of models of dynamical electroweak symmetry breaking. We will show that the…
We investigate the potential of the ILC for measuring anomalous quartic gauge couplings, both in production of three electroweak gauge bosons as well as in vector boson scattering. Any new physics that could possibly couple to the…
We study the impact of LEP2 constraints on the dimensionless coefficients of the electroweak chiral Lagrangian on the precision observables using the improved renormalization group equations. We find that the current uncertainty in the…