EPoS Contribution
EPoS Contribution
Time-Resolved AU-Scale Outflow Trajectories Traced by Masers in the IRAS16293-2422 Core

Al Wootten
NRAO, Charlottesville, Va, USA
The motions of water masers associated with the nearby low-mass IRAS16293-2422 system were measured over four epochs separated by several weeks from each other. The masers trace outflows originating from two separate origins consistent with locations at the sources A1 and A2. The flow near A2 agrees in position angle (60$^o$) with recent observations of bipolar ejection of ionized material in that source, which show a projected velocity of 30 to 80 km s$^{?1}$ away from A2. Over the course of our observations, a little over three months, this maser separated from the fiducial maser nearly 4 AU, which translates to a transverse velocity of 65 km s?1, in agreement with the velocities observed in the ionized plasma a decade later.
Caption: A closeup view of the masers profile in April near A1 in IRAS16293-2422. One tickmark is 0.01 arcsec, or about 1.4 AU at a 140pc distance to the source. The bright spot near center is a center of symmetry for blue and redshifted features, and contains components of both. Clearly the outflow commences extremely close to the spot, arguably within a distance less than the distance of Mercury from the Sun in the solar system.
M. Claussen, NRAO, USA
K. Marvel, American Astronomical Society, USA
B. A. Wilking, U. Missouri St. Louis, USA
Key publication