Search

Differently from the canonical seesaw mechanism, which is grounded in grand unified theories, the inverse seesaw mechanism lacks a special framework that realizes it naturally. In this work we advocate that the 3-3-1 model with right-handed neutrinos has such an appropriate framework to accommodate the inverse seesaw mechanism. We also discuss the smallness of the lepton number violating mass and estimate the branching ratio for the rare lepton flavor violation process μ → eγ. [ABSTRACT FROM AUTHOR]

In this work we build a gauge model based on the SU(3)c ⊗ SU(3)L ⊗ U(l)N symmetry with heavy neutrinos and show that we can have two wealdy interacting cold dark matter candidates in its spectrum. This is achieved by noticing that a global U(1) symmetry can be imposed on the model in such a way that the stability of the dark matter is guaranteed. We obtain their relic abundance and analyze their compatibility with recent direct detection experiments, also exploring the possibility of explaining the two events reported by CDMSII. An interesting outcome of this 3-3-1 model, concerning direct detection of these WIMPs, is a strong bound on the symmetry breaking scale, which imposes it to be above 3 TeV. [ABSTRACT FROM AUTHOR]

The minimal 3-3-1 model is perturbative until energies around 4-5 TeV, posing a challenge to generate neutrino masses at eV scale, mainly if one aims to take advantage of the seesaw mechanism. As a means to circumvent this problem, we propose a modification of the model such that it accommodates the type I and type II seesaw mechanisms altogether. We show that the conjunction of both mechanisms yield a neutrino mass expression suppressed by a high power of the cutoff scale, M5, in its denominator. With such a suppression term, we naturally obtain neutrino masses at eV scale when M is around few TeV. We also investigate the size of lepton flavor violation through the process µ → ey. [ABSTRACT FROM AUTHOR]

We investigate the Higgs boson production through gluon fusion and its decay into two photons at the LHC in the context of the minimal 3-3-1 model and its alternative version with exotic leptons. The diphoton Higgs decay channel presents an enhanced signal in this model compared to the standard model due to the presence of an extra singly charged vector boson and a doubly charged one. Prospects for the Higgs boson detection at 7 TeV center-of-mass energy with up to 10 fb-1 are presented. Our results suggest that a Higgs boson from these 3-3-1 models can potentially explain the small excess for mH ≤ 145 GeV observed at the LHC. Otherwise, if this excess reveals to be only a statistical fluctuation of the standard model backgrounds, severe constraints can be put on these models. [ABSTRACT FROM AUTHOR]