W49A - Bipolar Morphology

https://www.nrao.edu/archives/plugins/Dropbox/files/W49A-BipolarRegion_hi.jpg

Description

The bipolar W49A/A region as imaged with the VLA at (a) 3.6 cm, (b) 6 cm, and (c) 7 mm. This comparison indicates the importance of multifrequency, subarcsecond resolution imaging in determining the nature of UC HII regions like W49A/A. Source A has a distinctly bipolar morphology at the resolution of the 3.6 cm observations (beam =0.8"). The high-resolution 6 cm VLA image (beam =0.4"; Welch et al. 1987) indicates that the bipolar lobes are strongly edge-brightened. Finally a high-resolution (beam =0.04") 7 mm view of the source indicates that the central peak is itself an edge-brightened shell , having a center-to-edge brightness ratio consistent with an inclined ring of emission (see De Pree et al. 2000).

Creator

Legacy Astronomical Images

Rights

NRAO/AUI/NSF does not hold full copyright for this image. Contact the archivist for details.

Type

Legacy Astronomical Image

Object Name

W49A

Investigators

Chris De Pree, Miller Goss, Jack Welch, David Wilner

Telescope

Very Large Array (VLA)

Observation Date

2001-00-00

Type of Observation

continuum

Center of Image

RA 19:10:15.650, Dec: 9:6:5.500 (J2000)

Field of View

0.002778 x 0.002778 degrees

Link to NRAO Newsletter article

Notes

Contact the archivist for a high resolution tif of this image.

Series

Galactic Sources Series

Unit

Star Forming Regions Unit

Citation

Legacy Astronomical Images, “W49A - Bipolar Morphology,” NRAO Archives, accessed December 3, 2021, https://www.nrao.edu/archives/items/show/33487.