arXiv subjects
Publications and source records attributed to N. Poveda.
We consider the Two Higgs Doublet Model (2HDM) of type III which leads to Flavour Changing Neutral Currents (FCNC) at tree level. In the framework of this model we calculate the NLO contribution for b->s γand the branchings for the meson decays B^+ -> l^+ ν. We examine the limits on the new parameters λ_{bb} and M_{H^\pm}. We take into account the relationship between λ_{tt} and λ_{bb} coming from the validness of perturbation theory.
A supersymmetric version of the $SU(3)_L \otimes U(1)_X$ gauge model is presented. The model is embedded in a $SU(6)_L \otimes U(1)_X$ gauge group and it has been built up completely quiral anomaly free and without any exotic charges in the fermionic content. The Minimal Supersymmetric Standard Model can be seen as an effective theory of this larger symmetry. We analyze how the spectrum of the new model can shift the upper bound on the CP-even Higgs boson and we find that it can be moved up to 143 GeV.
Anomalous moments of the top quark arises from one loop corrections to the vertices $\bar t t g$ and $\bar t t γ$. We study these anomalous couplings in different frameworks: effective theories, Standard Model and 2HDM. We use available experimental results in order to get bounds on these anomalous couplings.