Thesis

Search for Higgs production in association with top quark pairs

• Call:

  IDPASC Portugal - PHD Programme 2015

• Academic Year:

  2015 / 2016

• Domain:

  Experimental Particle Physics

• Supervisor:

  Michele Gallinaro

• Co-Supervisor:

  Joao Varela

• Institution:

  Instituto Superior Técnico

• Host Institution:

  Laboratório de Instrumentação e Física Experimental de Partículas

• Abstract:

  The subject of this thesis is the search for Higgs production in association with top quark pairs. The top quark pair produced in association with the Higgs boson – ttH channel - with subsequent Higgs decays is interesting because the rate of this process depends on the couplings of the Higgs boson to the top quark as well as to the final state searched for. Measuring these couplings will help to determine whether the new boson observed at the Large Hadron Collider (LHC) with a mass of 125 GeV is indeed the Higgs boson with SM properties. In particular, the work plan is to analyze processes with top quarks in the final state. Top quarks are mostly produced in pairs at the LHC and, according to the SM, each one decays to a W-boson and a b-quark. Depending on the decay mode of the W-boson, either leptonic or hadronic, the final state may contain two, one or no leptons.