III: Generation of Turbulence and Wave-Induced Heating During Ionospheric Modification

PI将采用一种新的数值方法来研究高频加热器产生的朗缪尔波如何受到加热器强度分布高度变化的影响，以及-在较长的流体动力学时间尺度上-加热器引起的等离子体密度空间畸变。 为了量化电离层不均匀性对朗缪尔波能量的影响，PI将根据观测和理论模型，以数值方式确定驱动密度和加热器强度分布绝对不稳定性的修正阈值。 这两个部分的研究将共同回答：（1）加热器能量在电离层中（预处理前后）在何处以及如何转换为朗缪尔波？ (2)什么是朗缪尔波和电子的自洽动力学非线性演化？（3）在加热区外观察到的加速电子的分布是什么？

The PI will employ a new numerical approach for studying how the generation of Langmuir waves by the HF heater is influence by altitude variation in the heater intensity profile, and - on longer hydrodynamical time scales - by heater-induced spatial distortions in the plasma density. In order to quantify the effects ionospheric inhomogeneity has on Langmuir wave energy, the PI will numerically determine modified thresholds for driving absolute instabilities for density and heater-intensity profiles based on observations and theoretical models. Together, these two components of the research will answer: (1) where and how is heater energy conve3rted to Langmuir waves in the ionosphere (before and after preconditioning)? (2) what is the self-consistent kinetic nonlinear evolution of Langmuir waves and electrons? And (3) what is the distribution of accelerated electrons observed outside the heated region?