An extended interval of perturbed magnetospheric conditions in November 2016 supported increased convection and sunward transport of plasmaspheric material. During this period of time the Magnetospheric Multiscale satellites, with their apogees along Earth's dusk‐side outer magnetosphere, encountered several cold plasma density structures at the same time as plasma bulk flows capable of accelerating hidden cold plasma occurred. Investigating the charged particle and fields data during two subintervals showed that the satellites made direct measurements of cold plasmaspheric ions embedded within multicomponent hot plasmas as well as electromagnetic emissions consistent with electromagnetic ion cyclotron (EMIC) waves. The complex in situ ion composition measurements were applied to linear wave modeling to interpret the impacts of cold and hot ion species on wave growth and band structure. Although the waves for both intervals were predicted to have peak growth rate below Ω_He+, substantial differences were observed among all other dispersive properties. The modeling also showed EMIC waves generated in the presence of heavy ions had growth rates and unstable wave numbers always smaller than predicted for a pure proton‐electron plasma. The results provide implications for future investigation of EMIC wave generation with and without direct measurements of the cold and hot plasma composition as well as of subsequent wave‐particle interactions.

中文翻译：

---

冷热等离子体成分测量在研究对黄昏侧电磁离子回旋波的影响中的应用

2016年11月磁层大气状况的延长间隔支持了对流层和等离子层物质向阳输送的增加。在这段时间里，磁层多尺度卫星的最高点沿地球黄昏侧的外磁层，同时遇到了能够加速隐藏的冷等离子体的等离子体大体积流，同时遇到了几种冷等离子体密度结构。调查两个子间隔期间的带电粒子和场数据表明，卫星直接测量了嵌入多组分热等离子体中的冷等离子体球离子以及与电磁离子回旋加速器（EMIC）波一致的电磁辐射。将复杂的原位离子成分测量结果应用于线性波建模，以解释冷离子和热离子种类对波生长和能带结构的影响。尽管两个时间间隔的波都预测其峰值增长率低于Ω_{He +}，在所有其他色散特性之间观察到实质性差异。该模型还显示，在存在重离子的情况下产生的EMIC波具有增长速度，不稳定波数始终小于纯质子电子等离子体的预测值。结果为将来有没有直接测量冷，热等离子体成分以及随后的波粒相互作用的EMIC波的产生提供了启示。