Phenomenological Studies On The Physics Beyond The Standard Model With Neutrino And Dark Matter

Particle physics is the branch of physics that studies the interactions and prop-erties of elementary particles.The standard model（SM）of particle physics is based on quantum field theory,which successfully describes three fundamental interactions between elementary particles,including electromagnetic interactions,weak interac-tions,and strong interactions.With the discovery of the Higgs boson in 2012,the establishment of the SM has been basically completed.Although the SM has been fully tested in theory and experiment over the past few decades,there are still some phenomenologies that cannot be explained,such as the origin of neutrino mass,the identity of dark matter and the asymmetry between matter and antimatter in the Universe.In addition,with development of theoretical and experimental techniques,some physical quantities measured experimentally have deviation from the predicted values of the SM.Therefore,the search for the physics beyond the SM has become one of the primary tasks in theoretical and experimental particle physics.The neutrino oscillation experiments have firmly established that neutrinos are massive.Due to the absence of the right-handed neutrino field in the SM,neutrinos cannot acquire Dirac mass terms as other fermions.As the only electrically neutral fermions in the SM,neutrinos can be either Dirac fermions or Majorana fermions.Although the mass of neutrinos has not been determined by current experiments,it is known that their masses are much smaller than other elementary fermions based on the upper limits of neutrino mass.In order to determine the type of neutrino mass and naturally introduce neutrino mass terms into the SM,many new physics models beyond the SM have been proposed.The existence of dark matter has been established,but its nature is not yet known to us.To determine the identity of the dark matter is one of the most important frontiers in particle physics.Based on the properties of dark matter,there is no suitable particle in the SM that can serve as candidate for dark matter.Hence,dark matter candidates can only be found in new physics models beyond the SM.In the phenomenological studies on the physics beyond the SM,it is an interesting question to consider the correlation between the origin of neutrino mass and dark matter.Accurate testing of the SM is one of the important method to search for new physics.The anomalous magnetic moments of the muon and electron is the most precise type of measurement in particle physics experiments,but there has been a significant deviation between the theoretical and experimental values.The anomalies also include the ratios R_K（*）and R_D（*）in B-decays,pointing towards the lepton flavor universality violation.These intensity frontier precision measurements are crucial to probe the physics beyond SM.In this thesis,we have investigated the mechanism of neutrino mass origin,the identity of dark matter,the matter-antimatter asymmetry in the Universe and the anomalous phenomena observed,and studied the correlations between them.We per-form a detailed study of scalar dark matter with triplet Higgs extensions of the SM in order to study the flavor structure and explain the cosmic ray electron and positron spectrum reported by AMS-02 and DAMPE.We find that the hybrid triplet Higgs portal model can provide much better fit,especially for the inverted hierarchy neu-trino mass scenario.We also perform a fit to the DAMPE electron/positron data using the hybrid triplet Higgs portal model and find that the NH scenario has favored re-gion for fitting both the AMS-02 and the DAMPE signals.We construct a scotogenic Georgi-Machacek model by extending the SM with a Higgs doublet,two Higgs triplets and vector fermion doublets,in order to study common origin of neutrino mass,dark matter relic density and asymmetry of between matter and antimatter in the Universe.In this model,the neutrino masses are generated via one-loop diagram,the lightest neutral scalar particle originating from the mixing of scalar triplets can serve as the dark matter candidate and the leptogenesis mechanism is implemented for generating matter-antimatter asymmetry from decaying vector fermions.We extend the contents of the SM by introducing Te V-scale scalar leptoquarks to generate neutrino masses and explain some current observed deviations from the SM predictions,including the anomalous magnetic moments of charged leptons and B-physics anomalies.We study the relevant experimental constraints and conclude there is an appropriate parameter space accommodate to combined explanation for these anomalies and deviations.