GEM: Mode Conversion and Kinetic Alfven Waves at the Magnetopause and Their Effects in the Magnetosphere

从太阳风到磁层的质量和动量的传输仍然是一个重要但尚未完全了解的问题。这项提议将研究波诱导的粒子扩散过程作为日侧磁层顶的一种传输机制。特别是，该小组将研究磁流体动力(MHD)快模波到动能Alfven波(KAWS)的转换过程。改用KAWS可能是一种有效的运输机制。这里涉及的过程在实验室和天体物理等离子体以及磁层顶中可能是非常重要的。这项研究是基础等离子体物理研究的一个重要组成部分。方法是使用混合模拟(自洽电磁场中的动能离子和流体电子)来研究局部边界层中的模式转换。该小组将研究1)模式转换的三维非线性物理，2)由自洽产生的前震压缩波引起的模式转换的物理，3)模式转换的观测特征和模式转换对行星际磁场(IMF)和太阳风条件的依赖，4)由模式转换引起的KAW与由重联引起的KAW之间的差异，5)KAWS通过Poynting通量和场向电流对电离层的影响。模拟结果将与THEMIS在磁层的观测和DMSP在电离层的观测进行比较。这项研究将为研究生提供支持。

The transport of mass and momentum into the magnetosphere from the solar wind remains an important but incompletely understood problem. This proposal will study wave-induced particle diffusive processes as a transport mechanism at the dayside magnetopause. In particular the team will investigate the processes involved in the conversion of magnetohydrodynamic (MHD) fast mode waves to kinetic Alfven waves (KAWs). The conversion to KAWs may be an effective mechanism for transport. The processes involved here may be very important in laboratory and astrophysical plasmas as well as at the magnetopause. This research has an important element of basic plasma physics research.The approach will be to use hybrid simulations (kinetic ions and fluid electrons in self-consistent electromagnetic fields) to investigate mode conversion in a local boundary layer. The team will investigate 1) the 3-D nonlinear physics of mode conversion, 2) the physics of mode conversion due to self-consistently generated foreshock compressional waves, 3) the observed signatures of mode conversion and the dependence of mode conversion on interplanetary magnetic field ( IMF) and solar wind conditions, 4) the differences between KAWs due to mode conversion and those due to reconnection and 5) the impact of KAWs on the ionosphere through Poynting fluxes and field aligned currents. Comparison will be made between the simulation results and THEMIS observations in the magnetosphere and DMSP observations in the ionosphere.The research will support a graduate student.