Abstract
We discuss 2-D MHD numerical simulations for the interaction of high-velocit y clouds with a magnetized Galactic disk. The initial magnetic field is oriented parallel to the disk, and we consider two different field topologies: parallel and perpendicular to the plane of motion of the clouds. The impinging clouds move in oblique trajectories and fall toward the plane with different initial velocities. The B-field lines are distorted and compressed during the collision, preventing the cloud from penetrating into the disk. The perturbation creates a complex, turbulent, pattern of MHD waves that induce oscillations on both sides of the plane, and can trigger the Parker instability . The field efficiently transmits the perturbation over a large volume, while acting like a shield that inhibits the mass exchange between halo and disk. For non-magnetized disk cases, the shocked layer generates a tail that oscillates, creating vorticity and turbulent flows along its trajectory.
