2015 Seminar List:
A massive envelope and a strong bipolar outflow are the two main structures characterizing the youngest protostellar systems.
In order to understand the physical properties of a bipolar outflow and the relationship with those of the envelope, we obtained a mosaic map covering the whole bipolar outflow of the youngest protostellar system L1157 with about 5" angular resolution in CO J=2-1 using the Combined Array for Research in Millimeter-wave Astronomy.
By fitting these observations of the whole bipolar outflow, we estimate its physical properties and show that they are consistent with multiple jets.
We also constrain a preferred precession direction.
In addition, we observed the central envelope structure with 2" resolution in the Lambda = 1.3 and 3 mm continua and various molecular lines: C17O, C18O, 13CO, CS, CN, N2H+, CH3OH, H2O, SO, and SO2.
All the CO isotopes and CS, CN, and N2H+ have been imaged.
We marginally detected the features that can be interpreted by a rotating inner envelope in C17O and C18O and by an infalling outer envelope in N2H+. We also estimated the envelope and central protostellar masses and found that the dust opacity spectral index changes with radius.