| Magnetic reconnection is a mechanism which can rapidly transfer the magnetic energy into kinetic and thermal energy,which has been widely accepted by physicists and proved directly or indirectly with observations.And the accelerating mechanism of high-energy ions and electrons is also an important problem being researched in magnetic reconnection.The various radiation phenomena in solar flare show that great number of energetic electrons can be created in such explosive events.Magnetic reconnection as an important mechanism to trigger the solar flares is closely related to these electromagnetic radiation phenomena in the course of flares.Observations show that electron acceleration in solar flares occurs in magnetic reconnection regions above the soft X-ray flare loops in the corona,which accelerated by a super-Dreicer electric field in a reconnecting current sheet appears to be the most direct way of producing electrons with the energy in range from 10keV to 10MeV.We use such a numerical simulation method and add test electrons to the electromagnetic field in magnetic Recormection,then study the electron acceleration problem and analyze the physics mechanism.The electromagnetic fields from two and half-dimensional hybrid simulating magnetic reconnection are used as the background.The stable driving Petschek reconnection model is used in simulation. Some electrons can be effectively accelerated by the inductive electric field during magnetic reconnection.The major reason is that electrons can be captured by the special electromagnetic configuration.The magnetic field in acceleration region is weak,but it just can capture the low speed electrons in x,z plane,thus electrons can be driven and accelerated by the inductive electric field Ey.The primary force to drive electrons to high speed is the electric field force.When the electrons are speedy enough,they can no longer be captured by the magnetic field configuration,are deflected by the magnetic field.The speed in y direction is transferred to the reconnection plane,forming as a high speed of outflow in x,z plane.Such electromagnetic configurations are few in the electromagnetic field in magnetic reconnection,which are near the magnetic island and X point.This mechanism may be useful to interpret the generation of relativistic ions in large impulsive flares.Some studies found that there are cavities in magnetic reconnection and these cavities are a nonlinear manifestation of the kinetic Alfvén wave.When the spatial scale of plasmas disturbance is close to the gyroradius of the ions or the inertial length of electrons,the dispersion relation of ordinary Alfven wave in the ideal magnetophydrodynamic(MHD)plasmas is revised,and Kinetic Alfven waves(KAWs) are the nonlinear structures of the KAWs and are formed as the dispersion effects and the nonlinear effects in the plasma attain equilibrium.Since both KAWs and SKAWs have the magnetic-filed-aligned electric field,these waves are applied to the acceleration and heating of plasmas in magnetosphere widely.It is very significant to study the physics characteristic of the SKAW.In the two-fluid model in the limit case ofα>>1(α=β/2Q,βis the ratio of the Thermal Pressure to the magnetic pressure,Q=m_e/m_i),the Solitary Kinetic Alfvén Waves(SKAWs)were simulated.When simulating the collision of two SKAWs,we found that after the collision,the two SKAWs would remain in their own shapes and speeds which they owned before.This indicates that the SKAWs have some properties of mass particles.The Sagdeev equation governing SKAWs can be reformed to KDV equation approximately in case of small-amplitude,so the behavior of the SKAWs is just like the standard solitons.The simulation also shows that there will be a reflection wave and a transmission wave when SKAWs are crossing the discontinuity to a higher density side.The transmission is a SKAW with amplitude increased and the reflection is a small amplitude disturbance.
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