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地球内、外辐射带电子通量的变化对于空间飞行器,尤其是中低轨卫星的防护有着非常重要的影响.基于回旋共振波粒相互作用的准线性理论,使用地基高频发射器发射电波调制低电离层背景电流可以人工激励ELF/VLF波,这些波能使辐射带相对论电子发生抛射角散射沉降进入大气层从而降低其生存期.为了定量地分析人工激励ELF/VLF波散射辐射带高能粒子的可行性,针对内、外辐射带,本文选取了两个典型区域:L=4.6和L=1.5.数值计算结果表明,在内、外辐射带由于ELF/VLF波的人工注入而造成的高能电子损失时间尺度很大程度上取决于冷等离子体参量α*(∝B2/N0,这里B是背景磁场,N0是电子数密度)、电波频谱特性和功率,以及与波发生回旋共振的电子能量.一般来讲,在外辐射带人工ELF/VLF哨声波散射相对论电子使之沉降到大气层要容易得多;低能量的高能电子(200 keV)要比高能量的相对论电子(500 keV)更有效地通过抛射角散射进入大气层.考虑到高频电波加热电离层激励的ELF/VLF波可能会被捕获在磁层空腔中,来回反射从而得到增强,因此在适当的条件下,地基高频加热装置发射足够的电波功率进入电离层诱导大幅度ELF/VLF波注入到内磁层,能够在1至3天的时间尺度内快速散射外辐射带相对论电子使之沉降,也能够在10天量级的时间尺度里散射生存周期一般为100天甚至更长的内辐射带相对论电子.
The variation of electron flux inside and outside the radiative band has a very important influence on the protection of spacecraft, especially for medium and low orbit satellites.Based on the quasi-linear theory of the cyclotron resonance wave particle interaction, the ground-based high frequency transmitter is used to transmit the radio wave modulation Low ionospheric background currents can artificially excite ELF / VLF waves, which can scatter and scatter the relativistic electrons in the radiation band into the atmosphere at a scattering angle to reduce their lifetime. In order to quantitatively analyze the ELF / VLF waves with artificial excitation, Feasibility, for the inner and outer radiation zones, two typical regions are selected in this paper: L = 4.6 and L = 1.5. The numerical results show that the energetic electrons due to the artificial injection of ELF / VLF waves The time scale of loss largely depends on the cold plasma parameter α * (αB2 / N0, where B is the background magnetic field, and N0 is the electron density), the spectral properties and power of the radio waves, and the electron energy cyclotron resonance with the wave. In general, it is much easier to scatter relativistic electrons in the out-band artificial ELF / VLF whistle waves to the atmosphere; low-energy, high-energy electrons (200 keV) Of the relativistic electrons (500 keV) scatter more efficiently into the atmosphere by the projectile angle Considering that the ELF / VLF waves excited by high-frequency waves heating the ionosphere may be trapped in the magnetosphere cavity and are reflected back and forth and thus enhanced Under appropriate conditions, the ground-based high-frequency heating device emits enough radio wave power into the ionosphere to induce a substantial ELF / VLF wave injection into the inner magnetosphere, which can rapidly scatter the external radiation band relativistic electrons in a time scale of 1-3 days Sedimentation can also scatter internal radiation relativistic electrons with lifetimes of 100 days or more on the 10-day scale.