The Relaxation of Reconnected Open Magnetic Field Lines in the Earth's Magnetosphere

Abstract

Magnetic reconnection is a fundamental and important physical process that can release magnetic energy and change magnetic topology. A statistic study of reconnected magnetic field lines has been carried out by Cluster spacecraft 1 during 58 current sheet crossing events. We calculated the values of $| {B}_{n}/B| $ at different distances from reconnection site to describe the loosing process of magnetic field lines. Our results suggest that current sheets in ion diffusion regions have small values of $| {B}_{n}/B| $ . As the distance from reconnection site increases, the reconnected magnetic field lines relax, and subsequently have relatively large values of $| {B}_{n}/B| $ . However, such large values of $| {B}_{n}/B| $ are found to be closely related to open magnetic field lines that connect the Earth's magnetosphere and the solar wind.