Plasma structures with enhanced dynamic pressure, density, or speed are often observed in Earth's magnetosheath. We present a statistical study of these structures, known as jets and fast plasmoids, in the magnetosheath, downstream of both the quasi‐perpendicular and quasi‐parallel bow shocks. Using measurements from the four Magnetospheric Multiscale (MMS) spacecraft and OMNI solar wind data from 2015–2017, we present observations of jets during different upstream conditions and in the wide range of distances from the bow shock. Jets observed downstream of the quasi‐parallel bow shock are seen to propagate deeper and faster into the magnetosheath and on toward the magnetopause. We estimate the shape of the structures by treating the leading edge as a shock surface, and the result is that the jets are elongated in the direction of propagation but also that they expand more quickly in the perpendicular direction as they propagate through the magnetosheath.

中文翻译：

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准垂直弓形激波下游高速射流和等离子体的演变

通常在地球的磁石中观察到具有增强的动态压力，密度或速度的等离子体结构。我们对准垂直弓形冲击和准平行弓形冲击下游的磁石中的这些结构（称为射流和快速等离子体）进行了统计研究。使用来自四个磁层多尺度（MMS）航天器的测量值和OMNI 2015-2017年的太阳风数据，我们提供了在不同上游条件下以及在距弓首冲击距离较宽的范围内对喷气机的观测结果。在准平行弓形激波下游观察到的喷气流可以更深，更快地传播到磁层，然后向磁绝顶传播。我们通过将前缘视为冲击面来估算结构的形状，