Interactions between magnetohydrodynamical shocks and denser clouds

A two-dimensional computer code, which was recently developed for magnetohydrodynamical (MHD) shock problems, is used to simulate the interaction between a MHD shock and a denser cloud. The cloud is modeled as a cylinder along the direction perpendicular to the simulation domain and with a circular cross section. The tangential part of the magnetic field is initially along the cylinder. Various Mach numbers for the incident shock and various density contrasts between the cloud and its surrounding are used. Detailed pictures for the interaction are provided, and important time and length scales involved in the interaction are given in this paper.