The Phenomenological Studies On Dark Matter In μNMSSM Model

The existence of dark matter has been supported by many astronomical observational evidences,among which the typical representative is the observation results of bullet galaxy clusters.The lightest neutrino of the supersymmetric standard model belongs to the WIMP particle and is a good candidate for dark matter particles.As dark matter detection experiments become more and more restrictive on the parameter space of this particle,the study of the expansion of the usual supersymmetric model has become very practical.This paper studies the μNMSSM model obtained by breaking the Z3 symmetry with a minimal μ term.Phenomenological methods are used to explore the feasibility of the Singlino-dominated lightest neutralino χ10 as a dark matter particle.Specifically,the properties of the particle as dark matter（such as parameter dependence,annihilation process,scattering with laboratory nucleons）and the survival of the parameter space under experimental constraints are studied in detail.After theoretical calculation and analysis,we found that the annihilation crosssections of the main dark matter annihilation process of χ10 all have a stronger effect on the dependency of parameters κ and λ.The spin-dependent（SD）cross section betweenχ10 and the laboratory nucleus has a weak dependence on the parameter κ.However,the spin-independent（SI）scattering cross section has a very sensitive dependence on the parameters λ and μtot,and these two parameters can be strongly restricted from direct dark matter detection experiments.In addition,the parameter x can also significantly change the scattering cross section.Further,we used high-energy physics calculation packages and statistical methods（such as Bayesian method and profile likelihood method）for numerical analysis.Considering the influence of Higgs particles on the research,we separately discussed the lightest and second lightest CP even Higgs particles as the standard model like Higgs bosons,namely,h≡h1 and h≡h2.The research results show that the best annihilation process of χ10 as a dark matter particle is χ10χ10→hsAs.Under the experimental limit of the experimental platform XENON-1T for SI scattering in 2018 and SD scattering in 2019,there is still a large area of survival area of cross-section for the scattering between χ10 and the experiment nucleon,where the best value of the SI cross-section is 10-48 cm2 and the lowest value is 10-51 cm2,and the best value of SD cross section is 10-44 cm2 and the lowest value is 10-46 cm2.The model parameter dependencies of experimental data tendencies are 2κ/λ>1,and（?）.The mass selection range of the experimental data preference is 240 GeV～407 GeV in the case of h≡h1 and the best value is 350 GeV,and 181 GeV～346 GeV in the case of h≡h2 and the best value is 250 GeV.The physical simulation results of the collider combined with the latest di-lepton case of ATLAS show that the current LHC experiment only has certain weak restrictions on the h≡h2 situation.Under the experimental limit of XENON-1T,there is still a large range of parameter space to survive for χ10 as a dark matter particle,and the LHC experiment cannot provide reliable limits for the mass parameter of χ10.Therefore,the current experimental sensitivity cannot provide sufficient data limits for the parameter space when χ10 is used as a dark matter particle.μNMSSM model’s Singlino-dominated lightest neutralino can be used as dark matter candidate particles,and its annihilation process can be passed throughχ10χ10→hsAs to achieve.