Phenomenological Study Of Charged-current Non-standard Neutrino Interaction

The Standard Model(SM)is the most successful theoretical model currently to describe the properties and interactions of elementary particles.A large number of experimental studies have proved that its predictions have very high accuracy.However,the neutrino mass,dark matter and dark energy problems show signs of new physics beyond the SM.It is generally believed that the SM is only an effective theory at the electroweak scale,and more fundamental theories need to be introduced to explain these problems at the high-energy scale.We focus on the problem that the small mass of neutrinos,which clearly requires new theories of physics beyond the SM.Most of these theories are often accompanied by new interactions between neutrinos and other fermions induced by vector or scalar particles,called non-standard neutrino interaction(NSI).NSI not only has a great impact on the precision measurement of neutrino oscillation experiments,it is also an important platform for searching for new physics in the high energy collider experiments.Many new physics models have predicted the new gauge boson W’,in which W’ can induce charged-current non-standard neutrino interaction(CC NSI).At present,there are few theoretical studies on the CC NSI.In order to discover the experimental signals of NSI in the current and future high-energy collider experiments,our focus is on studying the constraints of low-energy and high-energy experiments on the CC NSI induced by W’.Based on an overview of relevant theoretical knowledge,we first investigate the constraints of the low-energy experiments on the CC NSI parameters induced by W’,and the results show that the tightest low-energy constraint comes from the upper limit of the lepton flavor violating decay μ→eγ at the one-loop level.The theoretical constraints of W’-related parameters are studied from the aspects of perturbation unitarity of the ff→V1V2 process and W’ decays,and then the theoretical constraints of the CC NSI parameters are given.On the basis of these theoretical constraints,the possibilities of detecting the CC NSI at proton-proton collider and proton-electron collider are studied.We perform a Monte Carlo simulation of the signals of the pp→lν process and their backgrounds,and through some optimized kinematic cuts,the backgrounds are strongly depressed,while the signals can be well preserved.In terms of statistical significance,the expected constraints of the LHC and HL-LHC on the CC NSI parameters are obtained.Similarly,the sensitivities of the e-p→νej process to the CC NSI parameters induced by W’ are obtained at the LHeC and FCC-eh.The results show that the interference effect is not negligible and should be considered.Neglecting the influence of energy scale change on the CC NSI parameters,we found that the expected constraints on the CC NSI parameters at the LHC are about an order of magnitude tighter than those from low-energy observables.The sensitivities of LHeC to CC NSI parameters are similar to that of LHC,while the sensitivities of FCC-eh to CC NSI parameters are two orders of magnitude smaller than HL-LHC.