损失锥电子速度分布激发的哨声波  

Whistler Waves Excited by Loss-cone Distribution Electrons

作　　者：周立辉[1,2] 陆全明[1] 郭俊[3] 王水[1] 

机构地区：[1]中国科学技术大学地球和空间科学学院,合肥230026 [2]中国科学院空间科学与应用研究中心空间天气学国家重点实验室 [3]青岛科技大学数理学院

出　　处：《空间科学学报》2009年第4期402-408,共7页Chinese Journal of Space Science

基　　金：国家自然科学基金项目(40874075;40725013;40674093);中国科学院知识创新工程重要方向性项目(KZCX2-YWN28)共同资助

摘　　要：利用一维粒子模拟方法研究了损失锥电子速度分布激发的哨声波非线性演化过程,并与双麦克斯韦电子分布激发哨声波的情况进行了比较。结果表明,这两种情况下,在线性增长阶段哨声波的主导频率(能量最集中的一个频率)是一样的,波动的激发使得平行于背景磁场方向的电子温度有所提高。比较而言,在损失锥分布情况下,哨声波具有主导频率的波模可较早地被激发,而在线性增长阶段,哨声波的能量更倾向于集中在高频(短波长)波段。部分粒子被散射到损失锥中,而使损失锥分布得以补充。本文还研究了不同各向异性分布和磁场强度条件下的激发过程。One-dimensional particle-in-cell simulations are performed in this paper to investigate the nonlinear evolution of whistler waves excited by the electron temperature anisotropy of loss-cone distribution, and compared with the results of bi-Maxwellian distribution. The simulation results indicate that the dominant frequencies in linear growth stage, which contain the most power, are the same in both situations, and that the electron temperature parallel to the background magnetic field is enhanced by the excitation of the waves. The whistler waves with the dominant frequency can be excited earlier with loss-cone distribution and the power is more concentrated in higher frequency （shorter wavelength）. different magnetic fields are also The excitations of whistler waves in different anisotropies and studied

关 键 词：粒子模拟 损失锥分布 哨声波 

分 类 号：P353[天文地球—空间物理学]