Effects of electron pressure gradient in magnetic reconnection

The effects electron pressure gradient terms in the generalized Ohm's law to the magnetic reconnection of dayside magnetopause are studied by means of 3-D MHD electromagnetic code in the case of high plasma Beta and large ion inertial length. The electron pressure gradient term and Hall term are of the same order. The electron pressure gradient term reduces the velocity of electrons and protons in the reconnection region. Thus the field aligned current correspondingly decrease with velocity decrease of particles. Because the close connection between the core field and field aligned current, the core field generated in the reconnection region also decrease.