Curtain precipitation is a recently discovered stationary, persistent, and latitudinally narrow electron precipitation phenomenon in low Earth orbit. Curtains are observed over consecutive passes of the dual AeroCube‐6 CubeSats while their in‐track lag varied from a fraction of a second to 65 s, with dosimeters that are sensitive to >35‐keV electrons. This study uses the AeroCube‐6 mission to quantify the statistical properties of 1,634 curtains observed over 3 years. We found that many curtains are narrower than 10 km in the latitudinal direction with 90% narrower than 20 km. We examined the geographic, magnetic local time, and geomagnetic dependence of curtains. We found that curtains are observed in the late‐morning and premidnight magnetic local times, with a higher occurrence rate at premidnight, and curtains are observed more often during times of enhanced Auroral Electrojet. We found a few curtains in the bounce loss cone region above the North Atlantic, whose electrons were continuously scattered for at least 6 s. Such observations suggest that continuous curtain precipitation may be a significant loss of >35‐keV electrons from the magnetosphere into the atmosphere. We hypothesize that the curtains observed in the bounce loss cone were accelerated by parallel electric fields, and we show that this mechanism is consistent with the observations.

中文翻译：

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使用 AeroCube-6 估算的电子幕降水的统计特性

幕降水是近地轨道上最近发现的一种静止、持续、纬度狭窄的电子降水现象。在双 AeroCube-6 CubeSat 的连续通过中观察到窗帘，而它们的轨道滞后从几分之一秒到 65 秒不等，剂量计对 >35 keV 电子敏感。本研究使用 AeroCube‐6 任务来量化 3 年来观察到的 1,634 个窗帘的统计特性。我们发现，许多窗帘在纬度方向上的宽度都小于10公里，其中90％的宽度小于20公里。我们研究了窗帘的地理、当地磁时和地磁依赖性。我们发现，在当地时间上午晚些时候和午夜前，可以观测到帷幕，其中午夜前的发生率较高，并且在增强极光电射流期间，观测到帷幕的频率更高。我们在北大西洋上空的弹跳损失锥区域发现了一些帘子，其电子连续散射至少6秒。这些观测结果表明，连续的幕降水可能导致>35 keV 的电子从磁层到大气中的大量损失。我们假设在弹跳损失锥体中观察到的帘幕被平行电场加速，并且我们证明这种机制与观察结果一致。