The interaction of hydrodynamic shocks with self-gravitating clouds

We describe the results of 3D simulations of the interaction of hydrodynamic shocks with Bonnor-Ebert spheres performed with an Adaptive Mesh Refinement code. The calculations are isothermal and the clouds are embedded in a medium in which the sound speed is either four or ten times that in the cloud. The strengths of the shocks are such that they induce gravitational collapse in some cases and not in others and we derive a simple estimate for the shock strength required for this to occur. These results are relevant to dense cores and Bok globules in star forming regions subjected to shocks produced by stellar feedback.