AAS 195th Meeting, January 2000
Session 53. ISM: Ionized Gas
Display, Thursday, January 13, 2000, 9:20am-6:30pm, Grand Hall

[Previous] | [Session 53] | [Next]

[53.15] H2O Maser Emission in W49N

E. J. McGrath (Vassar College), W. M. Goss (NRAO), C. G. De Pree (Agnes Scott College)

We present observations from the Very Large Array (VLA) in A and B configuration at 43 GHz and 22 GHz of the energetic star forming region W49N. Maser features in this source extend between velocities -260 km/s and +270 km/s. Positions and fluxes were calculated for 312 H2O masers with resolutions between 0.045" and 0.30". The weak continuum was cross calibrated with a strong maser feature that appears at v=170.7 km/s in the line data. The masers were then aligned to the continuum by using this reference line at v=170.7 km/s. Alignment errors are at the level of ~0.01" (5.6x10-4 pc, or 115 AU at a distance of 11.4 kpc as determined by proper motion studies of Gwinn, Moran, & Reid 1992), which is a factor of ten better than previous observations. The center of outflow of these maser features appears to be located between two ultra-compact (UC) HII regions, within 0.2" of the bright source G2.

This work was supported by the NSF sponsored REU program. The National Radio Astronomy Observatory is facility of the National Science Foundation operated under a cooperative agreement by Associated Universities, Inc.

The author(s) of this abstract have provided an email address for comments about the abstract: elmcgrath@vassar.edu

[Previous] | [Session 53] | [Next]