The Nonlinear Evolution of Ion Cyclotron Waves in the Earth's Magnetosheath  

作　　者：郭俊 杨忠炜 陆全明 王水 

机构地区：[1]School of Mathematics and Physics,Qingdao University of Science and Technology [2]State Key Laboratory of Space Weather,Center for Space Science and Applied Research,Chinese Academy of Sciences [3]School of Earth and Space Sciences,University of Science and Technology of China

出　　处：《Plasma Science and Technology》2009年第3期274-278,共5页等离子体科学和技术（英文版）

基　　金：supported by National Natural Science Foundation of China (Nos.40725013,40674093);the Open Research Program Foundation of State Key Laboratory for Space Weather,Chinese Academy Sciences

摘　　要：With one-dimensional （l-D） hybrid simulations we investigate the nonlinear evolu- tion of the ion cyclotron waves excited by the H＋ and He2＋ temperature anisotropies, and analyze the evolution by using the wavelet analysis method. The results show that the proton cyclotron waves with the dominant frequency higher than the helium gyro-frequency （ΩHe = 0.5Ωp, with Ωp and ΩHe the proton and helium gyro-frequencies respectively ） are firstly excited, and then the helium cyclotron waves with the dominant frequency lower than the helium gyro-frequency are excited. The relation of our simulation results to the BIF（bifurcated） （there are two peaks in the wave spectrum： one above and one below ΩHe） and CON（continuous） （continuous spectrum from 0.1 Ωp to 1.0 Ωp） wave spectra observed in the magnetosheath are discussed.With one-dimensional （l-D） hybrid simulations we investigate the nonlinear evolu- tion of the ion cyclotron waves excited by the H＋ and He2＋ temperature anisotropies, and analyze the evolution by using the wavelet analysis method. The results show that the proton cyclotron waves with the dominant frequency higher than the helium gyro-frequency （ΩHe = 0.5Ωp, with Ωp and ΩHe the proton and helium gyro-frequencies respectively ） are firstly excited, and then the helium cyclotron waves with the dominant frequency lower than the helium gyro-frequency are excited. The relation of our simulation results to the BIF（bifurcated） （there are two peaks in the wave spectrum： one above and one below ΩHe） and CON（continuous） （continuous spectrum from 0.1 Ωp to 1.0 Ωp） wave spectra observed in the magnetosheath are discussed.

关 键 词：ion cyclotron wave hybrid simulation temperature anisotropy 

分 类 号：P183[天文地球—天文学]