1997A&A...317..563W

High-resolution radio continuum observations of the southern HII complex RCW49 are presented. The observations were carried out with the Molonglo Observatory Synthesis Telescope (MOST) at 0.843GHz, and the Australia Telescope Compact Array (ATCA) at 1.38 and 2.38GHz. Two wind-blown shells have been discovered in the core region of RCW49, the more massive of which surrounds the Westerlund 2 cluster and exhibits a remarkable blister structure. The second shell, surrounding the recently-discovered star WR20b, is an example of a Wolf-Rayet ring nebula.