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基于高斯分布的哨声波谱密度分布、偶极子背景磁场模型以及建立在卫星观测数据基础上的半经验电子密度纬度分布模型,对于等离子体层顶以外区域(4≤L≤7),计算了准线性当地及弹跳平均电子共振扩散系数,并估算了与磁层哨声波回旋共振导致的辐射带电子损失及加速时间尺度.结果表明,波粒共振相互作用区域取决于电子能量、波谱分布、电子赤道抛射角以及当地电子密度及背景磁场.哨声波共振频率除了与以上5个参量有关外,还与地磁纬度有关.赤道哨声波主要影响较低能量辐射带电子的加速,中高纬度哨声波主要作用于较高能量辐射带电子的沉降损失.对于较低能量(约200keV)的辐射带电子,磁层哨声波可以在几个小时内使之沉降,对于较高能量(约1MeV)的电子,则需要一到数天;对低能量(约200keV)电子的加热可以在数小时内完成,回旋加速较高能量(约1MeV)电子一般则需要3—4d.电子密度分布的改变能够明显影响电子共振损失时间尺度,但是对电子共振加速时间尺度的作用很小.随着电子密度增强幅度随纬度的上升而增大,电子共振损失时间尺度会随之增大,但是电子共振加速时间尺度基本上不变化.另外,哨声波幅度及频谱随L及纬度的分布也显著影响它对辐射带电子的共振扩散效果,这些作用一般要大于电子密度分布变化带来的影响.
Based on Gaussian distribution of the whistler spectral density, the dipole background magnetic field model and the semi-empirical electron density and latitude distribution model based on satellite observations, for the region outside the plasma dome (4≤L≤7) The results show that the region of resonant interaction of wavelets depends on the energy of the electron, the distribution of the electron spectrum, the distribution of the electrons The equatorial projectile angle and the local electron density and the background magnetic field.The whistle wave resonance frequency is related to the geomagnetic latitudes except for the above five parameters.The equatorial whistle wave mainly affects the acceleration of electrons with lower energy radiation band and the whistle wave in the middle and high latitudes For a lower energy (about 200 keV) radiant band electrons, the magnetospheric whistle wave can settle within a few hours, and for higher energies (about 1 MeV) of electrons, It can take a few days; the heating of a low-energy (about 200 keV) electron can be completed in a few hours and the cyclotron accelerates at a higher energy (about 1 MeV) The electron density distribution changes obviously affect the time scale of electron resonance loss, but it has little effect on the time scale of electron resonance acceleration.With the increase of electron density increasing with latitude, the electron resonance loss The time scale will increase, but the time scale of electron resonance acceleration basically does not change.In addition, the distribution of whistler wave amplitude and spectrum with L and latitude also significantly affects its resonance diffusion effect on the radiation band, and these effects are generally greater than Effect of changes in electron density distribution.