Infall and outflow around the HH 212 protostellar system

HH212 is a highly collimated jet discovered in H-2 powered by a young Class 0 source, IRAS 05413-0104, in the L1630 cloud of Orion. We have mapped around it in 1.33 mm continuum, (CO)-C-12 (J = 2-1), (CO)-C-13 (J = 2-1), (CO)-O-18 (J = 2-1), and SO (N-J = 5(6)-4(5)) emission at similar to 2."5 resolution with the Submillimeter Array. A dust core is seen in the continuum around the source. A flattened envelope is seen in (CO)-O-18 around the source in the equator perpendicular to the jet axis, with its inner part seen in (CO)-C-13. The structure and kinematics of the envelope can be roughly reproduced by a simple edge-on disk model with both infall and rotation. In this model, the density of the disk is assumed to have a power-law index of p = -1.5 or -2, as found in other low-mass envelopes. The envelope seems dynamically infalling toward the source with slow rotation because the kinematics is found to be roughly consistent with a free fall toward the source plus a rotation of a constant specific angular momentum. A (CO)-C-12 outflow is seen surrounding the H-2 jet, with a narrow waist around the source. Jetlike structures are also seen in (CO)-C-12 near the source aligned with the H-2 jet at high velocities. The morphological relationship between the H-2 jet and the (CO)-C-12 outflow, and the kinematics of the (CO)-C-12 outflow along the jet axis, are both consistent with those seen in a jet-driven bow shock model. SO emission is seen around the source and the H-2 knotty shocks in the south, tracing shocked emission around them.