论文标题
在弓冲击处漂移不稳定性上的随机离子和电子加热
Stochastic ion and electron heating on drift instabilities at the bow shock
论文作者
论文摘要
对垂直弓冲击中波含量的分析表明，离子的加热与低杂交饮用（LHD）不稳定性以及电子加热到电子循环（ECD）不稳定性有关。这两个过程均代表由两个不稳定性产生的电子吉拉迪端尺度上的电场梯度引起的随机加速度。随机加热是一种单个粒子机制，其中大梯度破坏绝热的不变性并将颗粒暴露于DC和波场直接加速。加速度由函数控制$χ= m_iq_i^{ - 1} b^{ - 2} $ div（$ \ mathbf {e} $），该工具代表了电磁场和颗粒之间的能量转移过程的一般诊断工具，以及局部电荷非中性无中性的量度。通过从磁层多尺度航天器（MMS）获得的多点测量值进行识别。 LHD不稳定性的来源是离子的磁性漂移，而对于ECD不稳定性，源是电子的EXB漂移。结论得到了霍尔离子推进器中ECD不稳定性的实验室诊断。
The analysis of the wave content inside a perpendicular bow shock indicates that heating of ions is related to the Lower-Hybrid-Drift (LHD) instability, and heating of electrons to the Electron-Cyclotron-Drift (ECD) instability. Both processes represent stochastic acceleration caused by the electric field gradients on the electron gyroradius scales, produced by the two instabilities. Stochastic heating is a single particle mechanism where large gradients break adiabatic invariants and expose particles to direct acceleration by the DC- and wave-fields. The acceleration is controlled by function $χ= m_iq_i^{-1} B^{-2}$div($\mathbf{E}$), which represents a general diagnostic tool for processes of energy transfer between electromagnetic fields and particles, and the measure of the local charge non-neutrality. The identification was made with multipoint measurements obtained from the Magnetospheric Multiscale spacecraft (MMS). The source for the LHD instability is the diamagnetic drift of ions, and for the ECD instability the source is ExB drift of electrons. The conclusions are supported by laboratory diagnostics of the ECD instability in Hall ion thrusters.
