Relationship between the locations of the midlatitude trough minimum in the ionosphere and plasmapause in the inner magnetosphere has been statistically investigated using global navigation satellite system (GNSS)‐total electron content (TEC) and electron density data obtained from the Arase satellite from March 23, 2017 to May 31, 2020. In this analysis, we identify the midlatitude trough minimum as a minimum value of GNSS‐TEC at subauroral and midlatitude regions, and determine the plasmapause as an electron density decrease by a factor of 5 or more within ΔL < 0.5 in the inner magnetosphere. As a result, the plasmapause does not always coincide with the midlatitude trough minimum in all magnetic local time (MLT) sectors under all geomagnetic conditions. During the geomagnetically quiet periods, the midlatitude trough minimum is located at higher and lower geomagnetic latitudes (GMLATs) of the plasmapause in the MLT ranges of 5–21 and 21–5 h, respectively. This implies that both the features could not be on the same magnetic field line. On the other hand, during the storm main phase, the midlatitude trough minimum and plasmapause move toward a low‐latitude region with day‐night and dawn‐dusk asymmetries and the correlation becomes highest, compared with that under other geomagnetic conditions. Especially, both the features mapped on the ionosphere at a height of 300 km exist near GMLAT in the afternoon‐midnight sectors. This suggests that the midlatitude trough and plasmapause are formed at almost the same location due to an enhanced subauroral polarization stream during the storm main phase.

中文翻译：

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利用GNSS‐TEC和Arase卫星观测资料确定中纬槽位置与血浆Pla象的关系

已使用全球导航卫星系统（GNSS）-总电子含量（TEC）和从Arase卫星获得的3月23日的电子密度数据，对电离层中纬度最低谷位置与内部磁层中等离子体暂停之间的关系进行了统计调查， 2017年至2020年5月31日。在此分析中，我们将中纬度谷最低值确定为极光下和中纬度地区GNSS-TEC的最小值，并确定等离子停留时间为电子密度在ΔL范围内降低5倍或更多。在内部磁层中<0.5。结果，在所有地磁条件下，等离子暂停在所有磁本地时间（MLT）扇区中并不总是与中纬度最低谷值一致。在地磁平静期，中纬度谷最低值分别位于5-21和21-5 h的MLT范围内的等离子暂停的较高和较低的地磁纬度（GMLAT）。这意味着两个特征不能在同一磁场线上。另一方面，在风暴主相期间，与其他地磁条件下相比，中纬度谷最低值和等离子体暂停向昼夜和黎明黄昏不对称的低纬度地区移动，并且相关性最高。尤其，午夜至午夜时分，在GMLAT附近都存在着海拔300 km的电离层上绘制的这两个特征。这表明由于风暴主相期间增强的极光下极化流，中纬度谷和等离子暂停形成在几乎相同的位置。