Sub‐Structures of the Separatrix Region During Magnetic Reconnection

Abstract

Utilizing data from the Magnetospheric Multiscale mission, the sub‐structures of the separatrix region during reconnection are investigated. A small current system in the separatrix region is embedded in the large Hall current system, which appears as a quadrupole current. This small current system has an opposite direction to the Hall current and cancels part of the Hall magnetic field. The formation of the quadrupole current is possibly related to the patchy parallel electric field. The electric field in the separatrix region can be divided into three sub‐layers according to the electron frozen‐in condition. En enhances in two outside sub‐layers, where the strong En is supported by the Hall term and electron pressure gradient term, and the nearly zero En, separating the enhanced electric fields, is caused by a small flow and electron density gradient. Our observations imply complex dynamics in the separatrix region during magnetic reconnection.

Effects of Electron Vortices on the Magnetic Structures in the Terrestrial Magnetosheath

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Observations of Energy Conversion Caused by Magnetic Reconnection at a Dipolarization Front

“…Magnetic reconnection is a rapid energy release process, where energy is converted from the magnetic field to particles by reconfiguring the topology of the magnetic field (e.g., Lu, Fu et al., 2022). Reconnection has been widely observed in the Earth's magnetosphere, such as foreshock region (Jiang et al., 2021; Liu et al., 2020), magnetosheath (Phan et al., 2018; Retinò et al., 2007; Wang et al, 2021; Zhong et al., 2022), magnetopause (Burch et al., 2016; Huang et al., 2021; Wang et al., 2019; Zhou et al., 2021), and magnetotail (Huang et al., 2018, 2022; Jiang et al., 2019, 2022; Torbert et al., 2018; Zhou, Deng, et al., 2019). Recently, a new kind of reconnection called electron‐only reconnection, where ions don't respond to the reconnection process, is reported (Phan et al., 2018).…”

Observations of Tilted Electron Vortex Flux Rope in the Magnetic Reconnection Tailward Outflow Region

“…Magnetic reconnection is a universal and explosive energy conversion process in space (e.g., Burch et al., 2016; Huang et al., 2012a, 2018a; Jiang et al., 2022; Torbert et al., 2018; Zhou et al., 2019). Flux rope (FR) is a 3‐D helical magnetic structure, and it can be generated by a single X‐line reconnection and multiple X‐lines reconnection (e.g., Daughton et al., 2006, 2011; Deng et al., 2004; Fermo et al., 2012; Fu et al., 2017; Huang et al., 2016, 2018b, 2019; Sibeck et al., 1984; Slavin et al., 2003a; Zhong et al., 2018).…”