Speaker
Description
One of the currently most widely researched questions in particle physics is “What is dark matter?”. The Stealth Dark Matter theory identifies it with a stable state in a new, strongly coupled, dark sector extending the Standard Model. The constituents of the new sector, the dark quarks, form bound states in analogy with the SM QCD sector, giving rise to dark mesons, some of which can decay into SM states through Higgs interactions. In my talk I will present the first dedicated search for dark mesons at the LHC, based on gaugephobic Stealth Dark Matter. We search for pair production of dark pions, produced either resonantly via a dark rho or through Drell Yan production, that subsequently decay into top and bottom quarks. The search is done with the full Run 2 dataset with both the SU(2)R and SU(2)L models, with dark pion masses ranging from 200 GeV to 1200 GeV, and with the dark rho at least twice as heavy as the dark pion. Two final states are considered, the all-hadronic and the 1-lepton channel. The all-hadronic channel will have a result public by the time of this talk and the preliminary results will be discussed. My own work is focused on the 1 lepton channel in which the signature contains up to 8 quarks out of which 4 come from b-jets. I will describe how we faced this challenging final state, as well as the large differences in kinematics over the large signal grid, and any results we might have at the time of the talk.
