Mass enhancement and critical behavior in technicolor theories
نویسندگان
چکیده
منابع مشابه
Mass enhancement and critical behavior in technicolor theories.
Quark and lepton masses in technicolor theories can be enhanced if the high energy, extended technicolor (ETC) interactions play an important role in electroweak symmetry breaking. This happens when the ETC coupling and the technicolor gauge coupling at high energies lie close to a certain critical line. The enhancement has been associated with the existence of composite scalars made mainly of ...
متن کاملTechnicolor Theories with Negative S
We show that the pseudo Nambu–Goldstone boson contribution to the Peskin–Takeuchi electroweak parameter S can be negative in a class of technicolor theories. This negative contribution can be large enough to cancel the positive techni-hadron contribution, showing that electroweak precision tests alone cannot be used to rule out technicolor as the mechanism of electroweak symmetry breaking. PACS...
متن کاملNonoblique corrections in technicolor theories revisited.
In extended technicolor (ETC) theories, while the sideways ETC boson exchange decreases the width Γb ≡ Γ(Z → bb̄), the flavor-diagonal ETC boson exchange tends to increase it, and the ETC-corrected Rb ≡ Γb/Γhad value could agree with recent measurements. The τ asymmetry parameter may also increase in a way consistent with experiment. The weak-interaction ρ parameter receives a correction from di...
متن کاملComposite Scalars at LEP: Constraining Technicolor Theories
LEP I and LEP II data can be used to constrain technicolor models with light, neutral pseudo-NambuGoldstone bosons, P. We use published limits on branching ratios and cross sections for final states with photons, large missing energy, jet pairs, or bb pairs to constrain the anomalous PZZ, PZγ, and Pγγ couplings. From these results, we derive bounds on the size of the technicolor gauge group and...
متن کاملProbing technicolor theories with staggered fermions
One exciting possibility of new physics beyond the Standard Model is that the fundamental Higgs sector is replaced by a strongly-interacting gauge theory, known as technicolor. A viable theory must break chiral symmetry dynamically, like in QCD, to generate Goldstone bosons which become the longitudinal components of the W± and Z. By measuring the eigenvalues of the Dirac operator, one can dete...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Physical Review D
سال: 1991
ISSN: 0556-2821
DOI: 10.1103/physrevd.44.871