Effect Of Seed Electron Injection On Radiation Belt Energetic Electron

For many years the Earth's magnetosphere has been a mysterious space. As human space activities and space probes increased in recent years, for example, the United States RBSP project, SAMPEX satellite, more and more studies have been focused on dynamic evolution of energetic particle distributions in the Earth's radiation belts. Since 1958, radiation belts have drawn much attention, due to rapid and dramatic changes in fluxes of energetic elections and many spacecrafts happening there. So far, there are many scientific phenomena to be revealed and the outer radiation belt energetic particles would harm orbiting spacecraft and astronauts. This allows human beings to further continue in exploring the Earth's radiation dynamics evolution of high-energy electrons, in particular related to the acceleration of energetic electrons, loss process and transport processes.Part of the radiation belt high-energy electrons comes from the magnetotail with tens to hundreds ke V energy in substorms, usually called seed electrons. Seed electrons can become energetic radiation belt particles in gaining energy via various acceleration processes, including radial diffusion inward towards the Earth; resonant interaction between whistler-mode chorus and electrons. In the meanwhile, those injected seed electrons may also undergo a series of loss processes, including radial diffusion outwards away from the Earth and resonant scattering of energetic electrons by hiss and electromagnetic ion cyclotron waves.At first, we introduces the basic structure of the magnetosphere and magn etospheric plasma waves and describes the theory of particle motion in the ma gnetosphere.We then derive local and bounce-averaged diffusion coefficients by wave-p article interaction. We also solve the evolution of phase space density by the di ffusion equation in the pitch angle-momentum space. Specifically, we perform q uantitative modeling of the effect of injected seed electron on evolution of radi ation belt electrons driven by chorus waves.We use a three-dimensional Fokker–Planck diffusion equation which incorporates wave-particle inter-action, Coulomb collisions and radial diffusion. Numer ical simulations show that under the short time(?1 h) injection of low ener gy(0.1~0.2Me V) fluxes of radiation belt energetic electrons can increase durin g the entire storm period. During the main and recovery phases, such injection efficiently enhances chorus-driven acceleration of radiation belt energetic electr ons, allowing fluxes of energetic electrons by a factor of 1–2 orders higher tha n those in the absence of injection. The current results indicate that substorm i nduced electron injection must be incorporated to investigate the evolution of r adiation belt energetic electrons.