Little Higgs and Custodial SU ( 2 )
نویسنده
چکیده
In this note we present a little Higgs model that has custodial SU (2) as an approximate symmetry. This theory is a simple modification of the " Minimal Moose " with SO(5) global symmetries protecting the Higgs mass. This allows for a simple limit where TeV physics makes small contributions to precision electroweak observables. The spectrum of particles and their couplings to Standard Model fields are studied in detail. At low energies this model has two Higgs doublets and it favours a light Higgs from precision electroweak bounds, though for different reasons than in the Standard Model. The limit on the breaking scale, f , is roughly 700 GeV, with a top partner of 2 TeV, W ′ and B ′ of 2.5 TeV, and heavy Higgs partners of 2 TeV. These particles are easily accessible at hadron colliders.
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