Triggering of magnetic reconnection in the current sheet by shock waves.

Interaction of a shock wave with a current sheet is investigated by the two-dimensional numerical magnetohydrodynamic model. In accordance with the solar coronal conditions, the ratio of the thermal to magnetic pressures of 0.1 and the shock Alfven Mach number of about 1.25 are used. It is found that the shock wave initiates magnetic reconnection process in the current sheet. Further, it is found that the post-shock situation rather than the shock compression is a cause of the magnetic reconnection. Interaction of the shock with the current sheet results in formation of two shocks that propagate away from the current sheet on opposite sides followed by a rarefaction waves region. This dynamic situation causes the current sheet to become gradually thinner and the magnetic reconnection process is initiated probably due to the tearing-mode instability. Presented results support the idea that the solar flare can be triggered by the shock wave from a distant flare.