Abstract This paper exploits capabilities implicit in DMSP plasma and field data through which users may infer local IGRF magnetic fields ( B → 0 ), as well as components of magnetic perturbations ( δ B → ⊥ ) and plasma drift ( V → ⊥ ) vectors perpendicular to B → 0 . We use relations between V → ⊥ and δ B → ⊥ , associated with Region 2 (R-2) field-aligned currents (FACs), consistent with Faraday's law, to determine Alfvenic reflection coefficients (α). Early main-phase measurements from three DMSP satellites, F16, F17 and F18 during the 17 March 2015 storm confirm the predicted V → ⊥ and δ B → ⊥ relationships. Data also show that high-latitude limits of R-2 FACs lie close to the equatorward boundaries of precipitating auroral electrons. Measurable fluxes of down-coming, ring-current ions are restricted to the vicinity of this auroral boundary. It thus remains an open question as to what particle population is responsible for carrying the downward FACs (j||) and Poynting fluxes (S||), inferred from δ B → ⊥ measurements acquired over the full latitudinal ranges of storm-time R-2.

中文翻译：

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从 DMSP 推断的环形电流的早期主相电动力学

摘要 本文利用隐含在 DMSP 等离子体和场数据中的功能，用户可以通过这些功能推断局部 IGRF 磁场 ( B → 0 )，以及磁扰动 ( δ B → ⊥ ) 和等离子体漂移 ( V → ⊥ ) 向量的垂直分量。到 B → 0 。我们使用 V → ⊥ 和 δ B → ⊥ 之间的关系，与区域 2 (R-2) 场对齐电流 (FAC) 相关联，与法拉第定律一致，以确定阿尔芬反射系数 (α)。2015 年 3 月 17 日风暴期间三颗 DMSP 卫星 F16、F17 和 F18 的早期主相位测量证实了预测的 V → ⊥ 和 δ B → ⊥ 关系。数据还表明，R-2 FAC 的高纬度范围靠近极光电子的赤道边界。下降的环形电流离子的可测量通量被限制在这个极光边界附近。