On 17 January 2013, relativistic electron precipitation (REP) was observed on Balloon Array for Radiation Belt Relativistic Electron Losses (BARREL) payloads, National Oceanic and Atmospheric Administration Polar orbiting Operational Environmental Satellites (NOAA POES), and European Space Agency (ESA) MetOp between 2:44 to 15:04 h UT, scattered across dusk to early morning magnetic local time (MLT) sectors. The observations could be grouped into multiple observations of seven REP events spatially separated by more than 2 h in MLT and at least 1 h in UT. Almost all the events were localized in L shell with dL < 0.5 and MLT with dMLT < 3. A net loss of ∼5% of the relativistic electrons from the radiation belts is estimated between 2:44 to 15:04 h UT (∼13.5 h). A majority of atmospheric REP (nearly 75% through six REP events) was observed before the onset of a minor storm around 14:00 UT; the rest (25% through one REP event) was observed during the commencement of the storm which was followed by a major dropout of MeV electrons from the radiation belts during the main phase. However, no atmospheric precipitation was observed during the main phase, indicating that the dropouts may not have been caused by particle loss into the atmosphere.

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2013年1月17日大气相对论电子降水的量化

2013年1月17日，在辐射带相对论电子损失（BARREL）有效载荷，国家海洋和大气管理局极地轨道运行环境卫星（NOAA POES）和欧洲航天局（ESA）MetOp的气球阵列上观察到相对论电子沉淀（REP）在UT的2:44到15:04 h之间，散布在黄昏到清晨的磁性当地时间（MLT）扇区。可以将这些观察结果分组为对七个REP事件的多个观察结果，这些事件在MLT中间隔2小时以上，在UT中间隔至少1小时。几乎所有的事件中L壳层局部用DI <0.5和MLT与dMLT <3 A的净损失〜从所述辐射带被估计为15:04ħUT 2:44之间的相对论电子的5％（ 〜13.5小时）。在美国东部时间14:00左右发生小暴风雨之前，观测到大部分大气REP（通过6次REP事件近75％）。其余的（通过一次REP事件占25％）在暴风雨开始时被观测到，随后在主相期间MeV电子从辐射带大量掉落。但是，在主相期间未观察到大气降水，这表明该损失可能不是由于颗粒向大气中损失引起的。