Abstract

The ion pressure in the regions of ionospheric projections of the plasma mantle, polar cusp, low-latitude boundary layer, and the region of structured precipitation of the auroral oval during magnetic calm is studied based on data from the DMSP F6 and F7 low-altitude spacecraft. It is shown that the level of ion pressure in all of these regions does not depend on either the polarity or the value of the Bz component of the IMF. The ion pressure in the mantle varies from 0.02 to 0.06 nPa and does not depend on the magnitude of the solar wind dynamic pressure. The average pressure level is \(\left\langle {Pm} \right\rangle \) = 0.03 ± 0.01 nPa. In the cusp area at IMF Bz > 0, the ion pressure (Pc) does not depend on the solar wind dynamic pressure (Psw), while the pressure at IMF Bz < 0 increases significantly with the increasing in Psw. The average pressure level is \(\left\langle {Pc} \right\rangle \) = 1.0 ± 0.3 nPa, which is almost two orders of magnitude higher than that in the mantle. The ion pressure also increases with the solar wind dynamic pressure in both the LLBL and the auroral oval precipitation (AOP). The average pressure in the LLBL is \(\left\langle {{{P}_{L}}} \right\rangle \) = 0.27 ± 0.07 nPa, while in the AOP region its average value is two times lower. The MLT pressure pattern in LLBL shows a pronounced increase in the noon sector (~11–14 MLT), the value of which increases with increasing in the solar wind dynamic pressure. In the AOP region the pressure is distributed over MLT fairly evenly, which results in a significant pressure difference (ΔP = P_L – P_A) in the noon sector between the low-latitude boundary layer and the auroral oval.

中文翻译：

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白天极光降水不同区域的离子压力

摘要

基于DMSP F6和F7低海拔地区的数据，研究了等离子地幔，极尖，低纬度边界层的电离层投影区域和极光椭圆形的结构性降水区域中的离子压力。飞船。可以看出，所有这些区域中的离子压力水平均不取决于IMF的极性或Bz分量的值。地幔中的离子压力在0.02至0.06 nPa之间变化，并且与太阳风动压力的大小无关。平均压力水平为\（\ left \ langle {Pm} \ right \ rangle \） = 0.03±0.01 nPa。在IMF Bz > 0的尖端区域，离子压力（Pc）并不取决于太阳风动压（Psw），而IMF Bz <0时的压力随Psw的增加而显着增加。平均压力水平为\（\ left \ langle {Pc} \ right \ rangle \） = 1.0±0.3 nPa，这几乎比地幔中的压力高两个数量级。在LLBL和极光椭圆形降水（AOP）中，离子压力也随太阳风动压力而增加。LLBL中的平均压力为\（\ left \ langle {{{P} _ {L}}} \ right \ rangle \） = 0.27±0.07 nPa，而在AOP区域中，其平均值要低两倍。LLBL中的MLT压力模式表示中午扇区明显增加（〜11-14 MLT），其值随着太阳风动压力的增加而增加。在AOP区域，压力均匀分布在MLT上，这导致了低纬度边界层和极光椭圆之间的正午扇形区的压力差（ΔP = P _L – P _A）。