Modelo eletrofraco com dois dubletos e simetria extra local U(1).

Abstract

In this work we study two Higgs doublet models (2HDM) with extra local U (1) symmetry. We show how the U (1) symmetry can solve the problem of favor changing neutral currents, which arises in this model due to the presence of extra scalars. We describe how the anomalies from the addition of this new local symmetry can be canceled in various 2HDM types. Subsequently we study a particular type of 2HDM, wherein fermions are all neutral by U (1), known as Dark 2HDM. We discuss the features of this model and its phenomenology in accelerators, assessing the constraints coming from several high energy experiments and discussing the feasibility of Z0, the U (1) gauge boson, to be light (mZ0 . O(1) GeV), motivated by the explanation of astrophysical anomalies in the context of dark matter.