On the Gradient of the Electron Pressure in Anti-Parallel Magnetic Reconnection

【摘要】 We first perform a two-dimensional particle-in-cell simulation of anti-parallel magnetic reconnection to verify that in the electron diffusion region the reconnection electric field is mainly balanced by the gradient of the electron pressure.Then,by following typical electron trajectories in the fixed electromagnetic field of antiparallel reconnection,we calculate the gradient of the electron pressure.We find that the resulted gradient of the electron pressure is equal to the reconnection electric held.This indicates that in the electron diffusion region the reconnection electric field is balanced by the gradient of the electron pressure,which results from the electron nongyrotropic motions.Our result gives a microphysical explanation of the balance between the reconnection electric field and the gradient of the electron pressure.更多还原

【Abstract】 We first perform a two-dimensional particle-in-cell simulation of anti-parallel magnetic reconnection to verify that in the electron diffusion region the reconnection electric field is mainly balanced by the gradient of the electron pressure.Then,by following typical electron trajectories in the fixed electromagnetic field of antiparallel reconnection,we calculate the gradient of the electron pressure.We find that the resulted gradient of the electron pressure is equal to the reconnection electric Geld.This indicates that in the electron diffusion region the reconnection electric Geld is balanced by the gradient of the electron pressure,which results from the electron nongyrotropic motions.Our result gives a microphysical explanation of the balance between the reconnection electric Geld and the gradient of the electron pressure.更多还原