Spacecrafts observe signatures of duskside magnetic reconnection in the Earth's magnetotail associated with the presence of oxygen $\left({\mathrm{O}}^{+}\right)$ ions of ionospheric origin. The exact role of ${\mathrm{O}}^{+}$ ions in mediating reconnection remains largely unknown due to the local nature of observational techniques. We analyze results from global three-dimensional hybrid (kinetic ions, fluid electrons) simulations of ${\mathrm{O}}^{+}$ outflows and demonstrate that oxygen ions, escaping from the top of the ionosphere into the lobes, may cause disruptions on the duskside of the proton-formed magnetotail, adding up to its turbulent, unsteady nature. These ${\mathrm{O}}^{+}$ ions are shown to be capable of inducing magnetic flux ropes in the current sheet that thins out toward the dusk flank of the magnetotail due to Hall and ion kinetic effects. Unlike magnetohydrodynamics (MHD) simulations, where dawn-dusk magnetotail asymmetries may develop due to nonuniform ionospheric conductivity, the hybrid simulations demonstrate duskside tail disruptions on much faster ion gyroscales.

中文翻译：

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近地磁尾中 O+ 流出诱导的磁通绳：三维混合模拟


航天器观察到地球磁尾中黄昏磁重联的特征，这与电离层起源的氧 $（{\mathrm{O}}^{+}）$ 离子的存在有关。由于观测技术的局部性质，${\mathrm{O}}^{+}$ 离子在介导重新连接中的确切作用在很大程度上仍然未知。我们分析了 ${\mathrm{O}}^{+}$ 流出的全局三维混合（动离子、流体电子）模拟的结果，并证明氧离子从电离层顶部逃逸到波瓣中，可能会在质子形成的磁尾的黄昏侧造成破坏，从而增加其湍流、不稳定的性质。这些 ${\mathrm{O}}^{+}$ 离子被证明能够在电流片中感应出磁通绳，由于霍尔和离子动力学效应，磁通绳向磁尾的黄昏侧面变薄。与磁流体动力学 （MHD） 模拟不同，在磁流体动力学 （MHD） 中，由于电离层电导率不均匀，可能会形成磁尾不对称性，而混合模拟则展示了在更快的离子陀螺尺度上出现黄昏尾部中断。