GIM violation and new dynamics of the third generation

Abstract

In strong dynamical schemes for electroweak symmetry breaking the third generation must be treated in a special manner, owing to the heavy top quark. This potentially leads to new flavor physics involving the members of the third generation in concert with the adjoining generations, with potential novel effects in b-flavored and charm physics. We give a general discussion and formulation of this kind of physics, abstracted largely from top-color models which we elaborate in detail. We identify sensitive channels for such new physics accessible to current and future experiments.

The processe e in topcolour-assisted technicolour models

“…These new particles treat the third generation fermions differently from those in the first and second generations. The couplings of the gauge boson Z ′ relevant to our calculation can be written as [11,12]:…”

“…To obtain the top quark condensation and not form the bottom quark condensation, there must be tan θ ′ ≪ 1 [9,11].…”

Detecting the non-universal gauge boson Z at high-energy e+e collider

“…To completely avoid the problems, such as triviality and unnaturaless arising from the elementary Higgs in the SM, various kinds of dynamical models are proposed and among which T C2 models and flavor-universal T C2 models are very interesting because they can explain the large top quark mass and provide possible dynamics of elecroweak symmetry breaking(EWSB) [3]. A common feature of these models is that the SM gauge groups are extended at energy well above the weak scale.…”

“…The flavor-diagonal couplings of the non-universal gauge boson Z ′ to fermions, which are related our calculation, can be written as [3,7]:…”

“…New Physics(NP) should exist at energy scales around T eV . Many models of NP beyond the SM, such as string theory [1], grand unified theory [2], strong top dynamical models [3], predict the presence of massive Z ′ gauge bosons. If these new particles are discovered, they would represent irrefutable proof of NP, most likely that the SM gauge groups must be extended [4].…”