Effect of Chorus Latitudinal Distribution on Evolution of Outer Radiation Belt Electrons  

作　　者：肖伏良 李君求 唐立军 贺艺华 厉江帆 

机构地区：[1]School of Physics and Electronic Sciences,Changsha University of Science and Technology [2]State Key Laboratory of Space Weather,Chinese Academy of Sciences

出　　处：《Plasma Science and Technology》2009年第5期544-549,共6页等离子体科学和技术（英文版）

基　　金：National Natural Science Foundation of China (Nos.40774078,40774079 and 40874076);the Special Fund for Public Welfare Industry of China (Meteorology)CYHY200806024;the Visiting Scholar Foundation of State Key Laboratory for Space Weather,CAS

摘　　要：Primary result on the impact of the latitudinal distribution of whistler-mode chorus upon temporal evolution of the phase space density （PSD） of outer radiation belt energetic electrons was presented. We evaluate diffusion rates in pitch angle and momentum due to a band of chorus frequency distributed at a standard Gaussian spectrum, and solve a 2-D bounce-averaged momentum-pitch-angle Fokker-Planck equation at L = 4.5. It is shown that chorus is effective in accelerating electrons and can increase PSD for energy of ～1 MeV by a factor of 10 or more in about one day, which is consistent with observation. Moreover, the latitudinal distribution of chorus has a great impact on the acceleration of electrons. As the latitudinal distribution increases, the efficient acceleration region extends from higher pitch angles to lower pitch angles, and even covers the entire pitch angle region when chorus power reaches the maximum latitude λm = 45°.Primary result on the impact of the latitudinal distribution of whistler-mode chorus upon temporal evolution of the phase space density （PSD） of outer radiation belt energetic electrons was presented. We evaluate diffusion rates in pitch angle and momentum due to a band of chorus frequency distributed at a standard Gaussian spectrum, and solve a 2-D bounce-averaged momentum-pitch-angle Fokker-Planck equation at L = 4.5. It is shown that chorus is effective in accelerating electrons and can increase PSD for energy of ～1 MeV by a factor of 10 or more in about one day, which is consistent with observation. Moreover, the latitudinal distribution of chorus has a great impact on the acceleration of electrons. As the latitudinal distribution increases, the efficient acceleration region extends from higher pitch angles to lower pitch angles, and even covers the entire pitch angle region when chorus power reaches the maximum latitude λm = 45°.

关 键 词：wave-particle interaction acceleration of energetic electrons whistler-modechorus latitudinal distribution 

分 类 号：O462[理学—电子物理学]