A Heavy Top Quark and the Zbb̄ Vertex in Non-Commuting Extended Technicolor
نویسندگان
چکیده
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 mt ∼ 150 GeV there exist potentially large corrections to the Z decay width to b-quarks. Interestingly, in contrast to the situation in ETC models where the gauge-boson which generates the top-quark mass is a weak SU(2) singlet, the corrections may increase the Z → bb̄ branching ratio.
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