DARK MATTER AND HIGGS PHENOMENOLOGY BEYOND STANDARD MODEL

Abstract

The Standard Model (SM) of Particles is a very successful theory, which with the input of a fewfree parameters is capable to explain a plethora of experimental data. However, the Dark Matter(DM) and Dark Energy (DE) problem, the non-inclusion of gravity, the strong CP problem, thenature of the electroweak symmetry breaking and others, make us to believe that this is not theultimate theory.In this Thesis we explored two different ways to go beyond the SM looking at different problems.In the first work we would like to urge the exploration of the inert Two-Higgs doublet model(i2HDM), a minimal consistent DM model which is very well motivated by different theoreticaland experimental arguments. We present preliminary studies on DM relic density and colliderphenomenology. At the same time this model can be potentially tested at the LHC via differentsignatures for potentially accessible production of Dark Matter. We examine limits from presentday 8 TeV and projected 13 TeV LHC data, concentrating on limits from monojet processes.In the second work, we consider a possible extension of the SM where an effective Lagrangianis built, motivated by dynamical electroweak symmetry breaking models. In this particular modelwe consider that the Higgs boson and two new vector resonances come from a strongly interactingsector which originates the Fermi scale. Using the ATLAS measurements of the dijet spectrumwe set limits on the masses of the resonances. Additionally, we compute the Higgs boson decayinto two photons and find a small excess which is compatible with ATLAS measurements. Finallywe make prediction for Higgs-strahlung processes for the LHC running at 14 TeV.