Search for Dark Matter Produced in Association With a Higgs Boson in the Four Leptons Final State Using Run II Data at $\sqrt{s}$ = 13 TeV With the CMS Experiment

This thesis presents the search for dark matter candidates produced in association with a Higgs boson. The search is performed using proton proton collision data collected by CMSexperiment during Run II and corresponding to a total integrated luminosity of 137 $fb$$^{−1}$ atcenter of mass energy of 13 TeV. The Higgs boson decay channel considered in the searchis the Higgs decay to a pair of Z bosons which decay to four leptons with three possiblefinal states (4$\mu$, 4e and 2$e$2$\mu$). The experimental signature is characterized by significantamount of missing transverse energy $p$$_{T}^{miss}$ accompanied with four leptons from the HiggsTdecay products. This search is referred as “Mono-Higgs” search, where the Higgs boson isused as a candle to tag the presence of the dark matter candidate. The results obtainedare interpreted in the context of the two Higgs doublet simplified model extended by lightpseudoscalar. This model has been inspected with the Higgs → ZZ → 4l decay channel inCMS, for the fist time.