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S.M. Dougherty, J.S. Clark, I. Negueruela, T.W. Johnson & J.M. Chapman

Radio emission from the massive stars in Westerlund 1

(Volume 80 - Année 2011)
Article
Open Access

Abstract

The diverse massive stellar population in the young massive clusterWesterlund 1 (Wd 1) provides an ideal laboratory to observe and constrain mass-loss processes throughout the transitional phase of massive star evolution. A set of high sensitivity radio observations of Wd 1 leads to the detection of 18 cluster members, a sample dominated by cool hypergiants, but with detections among hotter OB supergiants and WR stars. Here the diverse radio properties of the detected sample are briefly described. The mass-loss rates of the detected objects are surprisingly similar across the whole transitional phase of massive star evolution, at ~ 10-5 Mo yr−1. Such a rate is insufficient to strip away the H-rich mantle in a massive star lifetime, unless the stars go through a period of enhanced mass-loss. The radio luminous star W9 provides an example of such an object, with evidence for two eras of mass-loss with rates of ~ 10−4 Mo yr−1.

To cite this article

S.M. Dougherty, J.S. Clark, I. Negueruela, T.W. Johnson & J.M. Chapman, «Radio emission from the massive stars in Westerlund 1», Bulletin de la Société Royale des Sciences de Liège [En ligne], Volume 80 - Année 2011, 134 - 138 URL : https://popups.ulg.ac.be/0037-9565/index.php?id=2587.

About: S.M. Dougherty

NRC-HIA, Penticton, Canada, and Institute for Space Imaging Science, University of Calgary, Canada

About: J.S. Clark

Open University, Milton Keynes, UK.

About: I. Negueruela

University de Alicante, Alicante, Spain

About: T.W. Johnson

NRC-HIA, Penticton, Canada, and University of Victoria, Victoria, BC, Canada

About: J.M. Chapman

Australia Telescope National Facility, Sydney, Australia