The principal aim of the LHC after the discovery of the last miss- ing particle in the Standard Model puzzel, the Higgs boson, in the Run I, is to search for new phenomena beyond the Standard Model. In the Run II where the total energy of the LHC has been increased, so many opportunities arise to search for phenomena beyond the SM. Some of these phenomena maybe associated with the production of di-boson final states. In this thesis, the channel that I focused in, is the production of an heavy

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... aviton which decays to two Z bosons, out of which one Z boson decays leptonically into two muons and the second decays into a q q ? pair . Because of the high mass of the graviton, the decay products of the Z bosons are heavily boosted. This may cause the q q ? pair to merge into one jet ("FatJet"). For the generation of the process I used the Monte Carlo generator MadGraph5. The MadGraph5 is a parton-level gen- erator, therefore the generated events should first pass through a parton shower Monte Carlo such as PYTHIA. The resulted particles are grouped into jets using an anti-kt jet-algorithm and the FastJet program. Then I calculate the invariant mass of the jets reconstructed by FastJet, and I select the events with a jet with mass close to the Z mass. The rest of the events are passed again trought FastJet to form two smaller jets, from which I select only the events with a pair of jets with an invariant mass close to the mass of the Z boson. Having selected the "interesting" events, that is events with either one "fatjet" or two jets consistent with the mass of the Z boson, I calculate the invariant mass of the system (two leptons plus the Fatjet or two leptons plus the two jets), which should be consistent with the mass of the generated Randall-Sundrum graviton. The aim of this thesis is to study the properties of the signal and define variables to maximize the signal selection over the background rejection. In this work I explain in detail how I succeed to essentially eliminate the background, by reducing its contri [...]