Outflows and Jets from Collapsing Magnetized Cloud Cores

Star formation is usually accompanied by outflow phenomena. There is strong evidence that these outflows and jets are launched from the protostellar disk by magneto-rotational processes. Here, we report on our three dimensional, adaptive mesh, magneto-hydrodynamic simulations of collapsing, rotating, magnetized Bonnor-Ebert-Spheres whose properties are taken directly from observations. In contrast to the pure hydro case where no outflows are seen, our present simulations show an outflow from the protodisk surface at ∼ 130AU and a jet at ∼ 0.07AU after a strong toroidal magnetic field build up. The large scale outflow, which extends up to ∼ 600AU at the end of our simulation, is driven by toroidal magnetic pressure (spring), whereas the jet is powered by magneto-centrifugal force (fling). At the final stage of our simulation these winds are still confined within two respective shock fronts. Furthermore, we find that the jet-wind and the disk-anchored magnetic field extracts a considerable amount of angular momentum from the protostellar disk. The initial spin of our cloud core was chosen high enough to produce a binary system. We indeed find a close binary system (separation ∼ 3R⊙) which results from the fragmentation of an earlier formed ring structure. The magnetic field strength in these protostars reaches ∼ 3kGauss and becomes about 3Gauss at 1AU from the center in agreement with recent observational results. Subject headings: accretion, accretion disks, magneto-hydrodynamics, ISM: clouds, evolution, methods: numerical