Abstract—

During geomagnetic substorms, the current sheet in the Earth’s magnetotail can transversely reduce in thickness from a few radii of the Earth (R_E) to one to several proton gyroradii, 250–2000 km. It is the key structure in which the energy of the magnetic field is stored and later released due to the development of instability and magnetic reconnection during the substorm period. Despite its small thickness, the thin current sheet has a complex multiscale structure with a hierarchy of embedded layers that determines its properties. During substorms, single-charged oxygen ions enter the Earth’s magnetotail from the ionosphere and their concentrations can be comparable to those of protons. The interaction of oxygen ions with the current sheet, which results in changes in its structure and properties, is not well studied. The self-consistent profiles of the magnetic field, current densities, and plasma in the multicomponent magnetotail plasma are analyzed in a wide range of system parameters within the hybrid model of the quasi-equilibrium current sheet. It is shown that the current sheet is a multiscale structure embedded in a wide plasma layer. The increase in the concentration of oxygen ions in the current sheet leads to its thickening and formation of additional embedded scale. At the same time, breaks characterizing the transition from the oxygen-ion dominated region in the current sheet to the proton- and electron-dominated region appear on the profiles of the magnetic field and current density. The amplitude of the current density of such an embedded layer decreases in proportion to the concentration of oxygen ions. The dependence of the embedding parameter on relative concentrations of heavy ions, as well as their thermal and drift velocities, is studied.

中文翻译：

---

氧离子对地球磁尾中薄电流片结构的影响

摘要—

在地磁亚暴期间，地球磁尾中的当前薄层可以从地球的几个半径（R _E）到250至2000公里的一到几个质子回旋半径。这是关键的结构，由于亚暴期间不稳定和磁重新连接的发展，磁场的能量被存储并随后释放。尽管厚度薄，但薄的电流板仍具有复杂的多尺度结构，该结构具有决定其特性的嵌入层的层次结构。在亚暴期间，单电荷的氧离子从电离层进入地球的磁尾，其浓度可与质子相当。氧离子与电流板之间的相互作用会导致其结构和性能发生变化，对此尚未进行很好的研究。磁场，电流密度，在准平衡电流表的混合模型中，在广泛的系统参数中分析了多组分磁尾等离子体中的等离子体和等离子体。结果表明，当前的薄片是嵌入宽等离子体层中的多尺度结构。当前板中氧离子浓度的增加导致其增稠并形成附加的嵌入水垢。同时，在磁场和电流密度的轮廓上出现了一些断点，这些断点从电流片中的氧离子占主导的区域过渡到质子和电子占主导的区域。这种嵌入层的电流密度的幅度与氧离子的浓度成比例地减小。嵌入参数对重离子相对浓度的依赖性，