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Fermion and scalar phenomenology of a 2-Higgs doublet model with $S_3$

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 نشر من قبل Ivo de Medeiros Varzielas
 تاريخ النشر 2015
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We propose a 2-Higgs doublet model where the symmetry is extended by $S_{3}otimes Z_{3}otimes Z_{3}^{prime }otimes Z_{14}$ and the field content is enlarged by extra $SU(2)_{L}$ singlet scalar fields. $S_3$ makes the model predictive and leads to viable fermion masses and mixing. The observed hierarchy of the quark masses arises from the $Z_{3}^{prime }$ and $Z_{14}$ symmetries. The light neutrino masses are generated through a type I seesaw mechanism with two heavy Majorana neutrinos. In the lepton sector we obtain mixing angles that are nearly tri-bi-maximal, in an excellent agreement with the observed lepton parameters. The vacuum expectation values required for the model are naturally obtained from the scalar potential, and we analyze the scalar sector properties further constraining the model through the $gamma gamma$ decay channel and the $T$ and $S$ parameters.



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