Using energetic ion composition data at the dayside magnetopause measured by Magnetospheric Multiscale (MMS) satellites, we study the responses of H⁺, O⁺ density (1–40 keV), and their ratio to geomagnetic activity and solar wind conditions; their spatial distributions in the XY_GSM plane for different ranges of the above parameters are presented as well. The dependencies of the H⁺ and O⁺ fluxes spatial distributions on different energy ranges are also investigated. Statistical results show that the dependencies of the H⁺ density on SYM‐H index, IMF By, and IMF Bz are weak, while the O⁺ density and its abundance (O⁺/H⁺) vary with SYM‐H index and solar wind dynamic pressure exponentially. The IMF directions not only affect the O⁺ density and its abundance but also play a major role in their spatial distributions. The O⁺ density shows duskside asymmetry under southward IMF with positive IMF By and shows dawnside asymmetry under northward IMF with negative IMF By. The influence of the dawn‐dusk IMF direction on dawn‐dusk asymmetry is significant. The positive and negative IMF By can strengthen the O⁺ duskside asymmetry and dawnside asymmetry when the IMF is southward and northward, respectively. Otherwise, as particle energy enhances from ~10 to ~35 keV, the H⁺ fluxes concentrate more on the duskside magnetopause boundary layer while the O⁺ fluxes dawn‐dusk asymmetry shows minor difference. This suggests that the H⁺ and O⁺ at energies below 40 keV experience different processes when they are transported to the dayside magnetopause boundary layer.

中文翻译：

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隔日磁层边界层中氧离子丰度和空间分布的统计研究：MMS观测

利用磁层多尺度（MMS）卫星在日间绝经期所含的高能离子组成数据，我们研究了H ⁺，O ⁺密度（1–40 keV）的响应及其与地磁活动和太阳风条件的比值；还给出了上述参数不同范围在XY _GSM平面中的空间分布。还研究了H ⁺和O ⁺通量空间分布对不同能量范围的依赖性。统计结果表明，H ⁺密度对SYM‐H指数，IMF By和IMF Bz的依赖性很弱，而O ⁺密度及其丰度（O ⁺ / H ⁺）随SYM‐H指数和太阳风动压呈指数变化。IMF方向不仅影响O ⁺密度及其丰度，而且在其空间分布中也起着重要作用。O ⁺密度在IMF南为正的情况下在IMF By下显示黄昏侧的不对称性，在IMF By为负的北向IMF下显示为黄昏侧的不对称性。黎明-黄昏IMF方向对黎明-黄昏不对称性的影响很大。当IMF分别向南和向北时，正负IMF By可以增强O ⁺黄昏侧的不对称性和黎明侧的不对称性。否则，随着粒子能量从〜10 keV增加到〜35 keV，H ⁺通量更多地集中在黄昏的磁层顶边界层上，而O⁺通量黎明黄昏的不对称性显示出微小的差异。这表明，当能量低于40 keV的H ⁺和O ⁺传输到日间磁更年期边界层时，它们经历不同的过程。