Oral Presentation

Numerical simulations of the reflection-symmetric bi-polar outflow HH211

Anthony Moraghan(ASIAA), Chin-Fei Lee (ASIAA), Po-Sheng Huang (ASIAA), Bhargav Vaidya (Torino)

Protostellar jets and outflows are an essential component in the star formation process. They regulate the rotating collapse of a star forming cloud into a young star by removing excess angular momentum from the system. This occurs as the removal of excess accretion material which is collimated and accelerated away at supersonic velocities from the central source by the bipolar jets. The jets then entrain ambient cloud material forming the bipolar outflows. Shocked emission produced by these bipolar outflows are observed as the Herbig Haro (HH) objects. By studying these large scale extended structures we learn about the small scale region around the heavily obscured protostar.

HH211 is an interesting bi-polar outflow. Recent SMA observations have shown it to possess a refection-symmetric wiggle. An explanation for this is that the jet source is part of a protobinary system.

Here we are testing this assumption through 3D hydrodynamic simulations of HH211 using the PLUTO code with a molecular chemistry and cooling module. The module allows us to plot synthetic CO emission channel maps and position-velocity diagrams for direct comparison with observations. This enables us to test the observational assumptions, and put constraints of the physical parameters of the HH211 source.