Low-mass stars like our Sun are formed in the dense cores of large molecular gas clouds. The star-formation process is hidden from view at optical wavelengths due to the large amounts of gas and dust surrounding the forming star, and even at infrared wavelengths the most deeply embedded protostars are often difficult to study. Most of this gas and dust is relatively cool, and observations at submillimeter wavelengths (a few tenths to one millimeter) are the best probes of the physical conditions during star-formation. Disks and bipolar outflows are now known to a be a integral part of the star-formation process. Observations of the thermal dust emission and spectral lines of molecules enable the physics and kinematics of the large scale envelope and the small-scale disk surrounding the protostar, and the outflow, to be studied in detail. The magnetic field geometry can be determined through polarization observations of charged dust grains. Importantly, interferometer observations allow most of the emission from the large-scale envelope to be filtered out, enabling high-resolution studies of the disks and inner- envelopes, where accretion of gas onto the protostar occurs, and where the initial conditions for planet formation are determined. Such observations are important as they inform us about the conditions under which our own Solar System and exoplanetary systems formed. Astronomers are using the SMA to study dense cores before the on-set of star-formation, and to probe the disks and outflows around protostars, in cores containing only one new star, and in cores containing small groups.

• PROSAC Project

CfA:

Tyler Bourke, David Wilner, Philip Myers, Paula Teixeira, Kevin Covey, Qizhou Zhang

ASIAA:

Chin-Fei Lee, Naomi Hirano, Shigehisa Takakuwa, Hsien Shang, Nagayoshi Ohashi, Ram Rao

On-going collaborators, previously at CfA

Jes Jørgensen, James Di Francesco, Paola Caselli, José Miguel Girart