Search

Motivated by the upcoming Higgs analyses, we investigate the importance of the complementarity of the Higgs boson chase on the low-mass weakly interacting massive particle (WIMP) search in direct detection experiments and the gamma-ray emission from the Galactic Center measured by the Fermi-LAT telescope in the context of the SU(3)C ⊗ SU(3)L ⊗ U(l)N. We obtain the relic abundance, thermal cross section, and the WIMP-nucleon cross section in the low-mass regime and network them with the branching ratios (BRs) of the Higgs boson in the model. We conclude that the Higgs boson search has a profound connection to the dark matter problem in our model, in particular for the case that (MWIMP < 60 GeV) the BR(H→2 WIMPs) ≳90%. This scenario could explain the gamma-ray emission from the Galactic Center observed by the Fermi-LAT telescope through the b... channel with a WIMP in the mass range of 25-15 GeV, while still being consistent with the current limits from XENON 100 and CDMSII. However, after the recent LHC measurements concerning the Higgs, this window has been completely forfended, implying that MWIMP > MH/2 and, consequently, ruling out any attempt to explain the Fermi-LAT observations, although still offering a region of the parameter space consistent with the current bounds. Lastly, we show that our model has a Standard Model-like Higgs boson for the regime that MWIMP > MH/2, by computing the BRs into bb, γγ and ττ. [ABSTRACT FROM AUTHOR]

Recent simulation studies indicate that right-handed neutrinos may be discovered at future high luminosity LHC runs as long as a new neutral gauge boson, Z', have been discovered first. In this case, when Z' is resonantly produced at the LHC it, subsequently, decays into a pair of right-handed neutrinos with mass up to TeV scale. Then the decay of these neutrinos leave as signature trilepton final states and/or same-sign dimuon and a boost diboson. The prospect of discovering right-handed neutrinos through this mechanism has been developed within Abelian gauge extension of the standard model. In this work we study the processes involved in this discovery mechanism within the framework of a 3-3-1 model. [ABSTRACT FROM AUTHOR]

The simplest non-Abelian gauge extension of the electroweak standard model, the SU(3)c ⊗ SU(3)L ⊗ U(1)N, known as the 3-3-1 model, has a minimal version which demands the least possible fermionic content to account for the whole established phenomenology for the well-known particles and interactions. Nevertheless, in its original form the minimal 3-3-1 model was proposed with a set of three scalar triplets and one sextet in order to yield the spontaneous breaking of the gauge symmetry and generate the observed fermion masses. Such a huge scalar sector turns the task of clearly identifying the physical scalar spectrum into a clumsy labor. It not only adds an obstacle for the development of its phenomenology, but implies a scalar potential plagued with new free coupling constants. In this work, we show that the framework of the minimal 3-3-1 model can be built with only two scalar triplets, but still triggering the desired pattern of spontaneous symmetry breaking and generating the correct fermion masses. We present the exact physical spectrum and also show all the interactions involving the scalars, obtaining a neat minimal 3-3-1 model far more suited for phenomenological studies at the current Large Hadron Collider. [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]