Related papers: The Oblique Corrections from the Diagonal ETC Inte…
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…
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…
Several aspects of the flavor-diagonal extended technicolor (ETC) gauge boson are reviewed. Among them are an increase of $R_b$ that could explain the LEP $R_b$ excess, a sizable, positive correction to the $\tau$ asymmetry parameter…
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…
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…
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…
In a realistic effective one-family extended technicolor(ETC) model without exact custodial symmetry, we calculate the one-loop corrections to the Z-b-(anti-b) and Z-tau-(anti-tau)vertices from the sideways and diagonal ETC bosons exchange.…
Extended technicolor theories generate potentially large corrections to the $\Zbb$ vertex which can be observed in current experiments at LEP.
The full solution of technicolor (TC) Schwinger-Dyson equations should include radiative corrections induced by extended technicolor (ETC) (or other) interactions. We verify that when TC is embedded into a larger theory including also QCD,…
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…
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…
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 calculate the Z boson propagator correction, as described by the S parameter, in technicolor theories with extended technicolor interactions included. Our method is to solve the Bethe-Salpeter equation for the requisite current-current…
In technicolor theories a large radiative correction to the Zbb vertex generally emerges, because of the large top quark mass and SU(2)_L gauge symmetry. The correction can give us an explanation for the deviation of the experimental value…
Extended technicolor theories generate potentially large corrections to the $\Zbb$ vertex. These can be observed in current experiments at LEP.
We investigate the impact of dark Abelian gauge bosons on the electroweak precision measurements at the one-loop level. The dark gauge boson couples to the standard model fermions generally via two kinds of mixing with the electroweak gauge…
We point out a set of operator identities that relate the operators corresponding to the oblique corrections to operators that modify fermion couplings to the gauge bosons as well as operators that modify triple gauge boson couplings. Such…
We relate all $C$-- and $P$--invariant anomalous triple vector--boson couplings to the oblique electroweak parameters. LEP constraints on the latter then yield the strongest and most general simultaneous bounds to date on the former. Even…
Non-decoupling effects of heavy particles present in beyond-the-standard models are studied for the triple gauge boson vertices $\gamma W^+W^-$ and $Z^0W^+W^-$. We show from a general argument that the non-decoupling effects are described…
We study diagonal and transition quark dipole operators in a class of extended technicolor (ETC) models, taking account of the multiscale nature of the ETC gauge symmetry breaking and of the mixing among ETC interaction eigenstates. Because…