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arXiv · hep-ph/0701040

Little Higgs models with a light T quark

R. Barcelo·M. Masip·M. Moreno-Torres
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Abstract

We study Little Higgs models based on a SU(3)_1 x SU(3)_2 global symmetry and with two scales (the two vacuum expectation values f_{1,2}) substantially different. We show that all the extra vector boson fields present in these models may be much heavier than the vectorlike T quark necessary to cancel top-quark quadratic corrections. In this case the models become an extension of the standard model with a light (500 GeV) T quark and a scalar Higgs field with a large singlet component. We obtain that the Yukawa and the gauge couplings of the Higgs are smaller than in the standard model, a fact that reduces significantly the Higgs production rate through glu-glu and WW fusion. The T-quark decay into Higgs boson becomes then a dominant Higgs production channel in hadron colliders.

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R. Barcelo, M. Masip, M. Moreno-Torres. 2007-05-24. Little Higgs models with a light T quark. https://doi.org/10.1016/j.nuclphysb.2007.05.014

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