The Origin of Collisionless Dissipation in Magnetic Reconnection

"The mechanism of collisionless reconnection in magnetized plasmas is studied in terms of coalescence of two flux tubes using implicit particle simulation. The motional electric field resulting from magnetic attraction generates the non-MHD (magnetohydrodynamic), scalar electrical potential of a quadrupole configuration across the x-point. This electric field transports the plasma and magnetic flux into and out of the diffusion layer, and also accelerates the finite mass electrons to produce the current J_parallel along the helical magnetic field. These processes provide equivalent dissipation which makes magnetic reconnection possible in collisionless magnetized plasmas.