Oblique penetration of solar-wind filaments into the magnetosphere

In this paper, a set of two-dimensional simulations for resistive magnetohy drodynamical equations are performed to investigate the interaction between a solar-wind filament and the magnetosphere when the filament is obliquely oriented with respect to the direction of the magnetospheric field. Detail ed pictures for the interaction are given. For typical parameters near the magnetopause, a filament with a sufficiently large excess flow velocity wil l penetrate into the magnetosphere, and will then be repelled back towards the magnetopause by the highly compressed and bent magnetospheric field. Fi nally, the filament will be smeared along the magnetospheric field near the magnetopause. When the angle is small, the filament will penetrate deeply into the magnetosphere before it is repelled back. Therefore there is a max imum depth a penetrated filament may reach into the magnetosphere. The effe ct of spontaneous reconnections behind a penetrating filament on the penetr ation appears to be negligible.