FORMATION OF FAST MAGNETOSONIC SHOCK-WAVES DURING A 2-CURRENT-LOOP COLLISION IN SOLAR-FLARES

We present a numerical simulation of the fast magnetosonic shock wave formation during a two-current-loop collision by using a magnetohydrod ynamical model. It is shown that the rarefaction waves are generated i n the initial stage when the two current loops start to collide. After the rarefaction waves propagate away from the excited region, the fas t magnetosonic waves with density enhancement can be produced for the simulation when the current strength of the loop is weak. As the curre nt becomes strong enough, the magnetosonic shock waves can be generate d in the direction perpendicular to that of the two-loop collision.