| The success of the Standard Model is unquestionable.It summarizes human understanding of the composition of elementary particle in the microscopic material world,and brings the other three interactions in nature,namely,strong interaction,weak interaction and electromagnetic interaction,into a unified theoretical framework.As the particles predicted by the standard model are discovered one by one,the quantitative predictions of the standard model are confirmed one by one,and its authenticity is also being increasingly verified.However,there are still many problems in nature that cannot be explained by the standard model,such as neutrino oscillation phenomenon,dark matter,dark energy,mass grade problem,baryon anti baryon asymmetry and CP violation.This paper focuses on the issue of dark matter.As early as the 1920s,astronomers proposed the possible existence of dark matter while observing the Milky Way.Modern cosmological theory estimates that the mass of dark matter accounts for about a quarter of the total matter in the universe,about five times that of ordinary baryonic matter.The gravity provided by baryonic matter and dark matter in the universe jointly maintains the stable structure of the current universe.Dark matter is an indispensable and important component of the universe,but the standard model does not directly provide the microscopic particle composition of dark matter.The type,interaction,and experimental detection of elementary particle of dark matter have become major frontier topics in current particle physics and cosmology.The Scotogenic model framework used in this paper has two dark matter candidates,the lightest singlet fermion and the lightest inert scalar η±,this paper studies the lightest singlet fermion N1 as a candidate for dark objects,N1 spin 1/2,and having odd parity under Z2 symmetries.The research of the paper focuses on the following aspects:(1)Only considering paired annihilation channels N1N1→l+l-vv.we obtain mass spectrum M1<Mη±+<M2<M3 for TeV-scale M1.(2)Considering that the mass spectrum η± can only decay to N1,Theμ-related Yukawa couplings |yiμ| are involved in the production of η± at muon collider.We investigates the dilepton and mono-photon signal research at a 14 TeV muon collider.In order to distinguish the signal from the relevant background as much as possible,case selection was made for the dilepton signature in the study,and the comparison showed that the dimuon signature was the most promising channel.With 200fb-1 data,the 14 TeV MuC is able to unravel most viable samples,except those with small Yukawa coupling |y1μ| or with compressed mass spectrum M1(?)Mη±.But when |y1μ| is too small,the ditau channel becomes more promising.The mono-photon signature μ+μ-→N1N1γ→γ+MET could probe the compressed mass region M1(?)Mη±.Masses of charged scalar η± and dark matter N1 can be further extracted by a binned likelihood fit of the dilepton energy.The combined result is Mη±=2650±7 GeV with M1=1577±9 GeV allowing the actual value within the 1σ range.The work of this paper is of great significance for the development of the Scotogenic model,providing new clues for the search of Fermi dark matter on future 14 TeV muon collider. |
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