Speaker
Description
Abstract
Recently, there has been great interest in beyond-the-Standard Model (BSM) physics involving new low-mass matter and mediator particles. One such model, U(1)T3R, proposes a new U(1) gauge symmetry under which only right-handed fermions of the standard model are charged, as well as the addition of new vector-like fermions (e.g., chi_t) and a new dark scalar particle (phi) whose vacuum expectation value breaks the U(1)T3R symmetry. For this work, we perform a feasibility study to
explore the mass ranges for which these new particles can be probed at the LHC. We consider the interaction pp -> chi_t + t + phi in which the top quark decays purely hadronically, the chi_t decays semileptonically (chi_t -> W + b -> I nu b), and the phi decays to two photons. The proposed search is expected to achieve a discovery reach with signal significance greater than 5sigma for chi_t masses up to 1.8 TeV and phi masses as low as 1 MeV, assuming an integrated luminosity of 3000 fb-1.
