A possible extension of the Standard Model that addresses the hierarchy problem
in a natural way involves the existence of a new strongly-interacting sector, of which
the Higgs boson would be a pseudo-Goldstone boson of a spontaneously-broken global
symmetry. One particular realization of this scenario, referred to as "Composite Higgs",
predicts the existence of new fermionic resonances...
The search for heavy Higgs bosons at the LHC represents an intense experimental program, carried out by the ATLAS and CMS collaborations, as well as the hunt of invisible Higgs decays and dark matter candidates. No significant deviations from the SM backgrounds have been observed in any of these searches, imposing important constraints over the parameter space of different new physics models...
Supersymmetric extensions of the standard model provides a solution the the hierarchy problem and the possibility to give observable signals at the LHC. When R-parity is broken and the right-handed neutrinos are included in the spectrum many interesting interpretations are possible. After a brief introduction of the simplest model including many useful interpretations and desirable properties,...
Analysis and implementations by the UBA group at ATLAS
In the Minimal Supersymmetric Standard Model (MSSM) searches for the heaviest CP-even and CP-odd Higgs H, A to tau-lepton pairs severely constrain the parameter region for large values of tanβ and light Higgs bosons H, A. We demonstrate how the exper- imental constraint can be avoided by new decays to light third-generation sfermions, whose left-right couplings to H can be maximised in regions...