Related papers: V,W and X in Technicolour Models
We study the one-loop sensitivity of the WWV (V=gamma, Z) vertex to the new massive gauge bosons predicted by the minimal SU_L(3) X U_X(1) model, which have unusual couplings to the standard model (SM) gauge bosons. A gauge-fixing procedure…
It has been recently argued that realistic models with warped extra dimensions can have Kaluza-Klein particles accessible at the Large Hadron Collider if a custodial symmetry, SU(2)_V \times P_{LR}, is used to protect the T parameter and…
We present the first calculation of the next-to-leading-order electroweak corrections to W-boson + jet hadroproduction including leptonic W-boson decays. The W-boson resonance is treated consistently using the complex-mass scheme, and all…
We update our analysis of technicolour theories with techniquarks in higher dimensional representations of the technicolour gauge group in the light of the new electroweak precision data on the Z resonance.
We suggest a criterion to minimize the amount of fine-tuning in a composite Higgs model. The paradigm of this type of model is the top-condensate model of Bardeen, Hill and Lindner (BHL). Although "minimally fine-tuned", this model failed…
We discuss the effects of isospin breaking which appear in the vertex corrections for $Zb \bar{b}$, $Z\tau^+\tau^-$ and $W\nu\tau$ in a one-family technicolor model without exact custodial symmetry. By means of the effective lagrangian…
We study the light vector and axial-vector mesons. According to the hadrogenesis conjecture the nature of the two types of states is distinct. The axial-vector mesons are generated dynamically by coupled-channel interactions based on the…
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…
The O(\alpha) electroweak radiative corrections to the process pp, ppbar\to W \to\ell^\pm\nu (\ell=e,\mu) are calculated. The O(\alpha) corrections can be decomposed into separately gauge invariant contributions to the W boson production…
We calculate the electroweak and finite width corrections to the decay of an unpolarized top quark into a bottom quark and a $ W $-gauge boson where the helicities of the $ W $ are specified as longitudinal, transverse-plus and…
Based on previous studies computing coefficients of the electroweak chiral Lagrangian from C.T.Hill's schematic topcolor-assisted technicolor model, we generalize the calculation to K.Lane's prototype natural topcolor-assisted technicolor…
We study the constraints on models of topcolor-assisted technicolor arising from measurements of high-$E_T$ jets and high-mass lepton pairs at the Tevatron collider. Existing data can eliminate models that have appeared in the literature.
A theoretical study of Goldstone boson scattering based on the chiral Lagrangian with vector meson fields is presented. In application of a recently developed novel approach we extrapolate subthreshold partial-wave amplitudes into the…
The cross-section for W^+W^- \to W^+W^- with arbitrarily polarized W bosons is calculated within the Electroweak Standard Model including the complete virtual and soft-photonic O(alpha) corrections. We show the numerical importance of the…
The measurements performed at LEP and SLC have substantially improved the precision of the test of the Minimal Standard Model. The precision is such that there is sensitivity to pure weak radiative corrections. This allows to indirectly…
Bosonic technicolor models accommodate fermion masses via a Higgs doublet that acquires a vacuum expectation value when technifermions condense. We point out that these models are severely constrained by vacuum stability if the Higgs boson…
We identify and compute the main corrections to $R_b$ in Topcolor theories. They are due to the top-pions, the pseudo-Goldstone bosons associated with the chiral symmetry breaking responsible for the top quark mass, and amount to -(1-4)%,…
If electroweak symmetry breaking is driven by a new strongly-coupled dynamical sector, one expects their bound states to appear at the TeV scale or slightly below. However, electroweak precision data imposes severe constraints on most of…
We study a class of leptogenesis models where the light neutrinos acquire their observed small masses by a symmetry-motivated construction. This class of models may naturally include three nearly degenerate heavy Majorana neutrinos that can…
We investigate the modeling of weak boson number densities for leptons and hadrons in practical calculations in the Standard Model. Working in the framework of the Effective $W$ Approximation (EWA) and in $R_\xi$ and axial gauges, we derive…