Probing vector-like top partner from same-sign dilepton events at the LHC

The standard model is a successful theory but is lacking a mechanism for neutrino mass generation as well as a solution to the naturalness problem.In the models that are proposed to simultaneously solve the two problems,heavy Majorana neutrinos and top partners are usually predicted to lead to a new decay mode of the top partner mediated by the heavy Majorana neutrinos:T→b W^+→b l^+l^+qq^1.In this paper,we will study the observability of such a new signature via the pair production process of a top partner pp→TT→2 b+l^±l^±+4 j in a model independent way.By performing Monte Carlo simulations,we present the 2σexclusion limits of the top partner mass and mixing parameters at the HL-LHC.