Crater Structure Behind Reconnection Front

Abstract

Magnetic reconnection is the physical process that converts the energy from the fields to the plasmas in space, astrophysical and laboratory plasmas. The Reconnection front (RF) is the structure generated in the reconnection outflow region and participates in the energy release budget. Here, we first report a novel crater structure of magnetic field behind the RF, which is well supported by both the in‐situ observations from the Magnetospheric Multiscale mission and kinetic particle‐in‐cell simulations. The theoretical explanations from the simulations suggests that the formation of the crater structure is possibly due to that high‐speed outflow electron jet from inner electron diffusion region constantly strikes the RF. From another perspective, the crater structure is the continuous impact of the electron jet. Our results can establish a new understanding of the RF and energy conversion during magnetic reconnection.

Guide Field Dependence of Energy Conversion and Magnetic Topologies in Reconnection Turbulent Outflow

“…We take advantage of the 2.5D PIC simulation code of GPIC (Xiong, Huang, Yuan, Jiang, Wei, et al, 2023;. The double Harris current sheet reconnection model has been used in previous studies (e.g., Xiong et al, 2022aXiong et al, , 2022bXiong et al, , 2022cHuang et al, 2014Huang et al, , 2024Huang, Zhou, et al, 2015;Zhou et al, 2012Zhou et al, , 2014. For the initial condition of the magnetic field, we set two localized perturbations in the same current sheet, and it forms multiple X points to generate turbulent outflow due to Kelvin-Helmholtz instability (e.g., Huang et al, 2017;Huang, Lu, et al, 2015;Lu et al, 2023).…”

In Situ Observations of Magnetic Reconnection Caused by the Interactions of Two Dipolarization Fronts

“…Thus, how to reduce the B normal and bypass the stabilization threshold is vital to the onset of reconnection in the magnetotail. magnetotail to the Earth (e.g., Birn et al, 2011;Fu et al, 2019;Huang et al, 2024;Nakamura et al, 2009). The typical features of a DF include an abrupt increase of B z within a short duration, a decrease in plasma density, and earthward plasma flow (e.g., Runov et al, 2009).…”

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

“…Dipolarization fronts (DFs) are the leading edge of high-speed plasma flow, which are essential carriers of mass, energy, and magnetic flux from the magnetotail to the Earth or other planets (e.g., Birn et al, 2011;Huang et al, 2024;Lin et al, 2023;Nakamura et al, 2002;Runov et al, 2009;Xu et al, 2021Xu et al, , 2022. As ion-scale tangential discontinuities between fast plasma flows and ambient plasmas, DFs are dynamic.…”