The very rich massive post - main - sequence star population of the open cluster Westerlund 1
نویسندگان
چکیده
We report the discovery of a population of Wolf-Rayet stars in the young Galactic open cluster Westerlund 1. In an incomplete shallow spectro-scopic survey, we find six nitrogen-rich (WN) and five carbon-rich (WC) WR stars. We also confirm the presence of a large population of yellow supergiants, some of which are candidate hypergiants. Given this population, Westerlund 1 is likely to be one of the more massive young clusters in the Local Group.
منابع مشابه
A hidden population of Wolf-Rayet stars in the massive galactic cluster Westerlund 1
We report the discovery of a hitherto undetected population of Wolf-Rayet stars in the young galactic open cluster Westerlund 1. Optical spectroscopy of the cluster identified 11 such objects; provisional classification suggests that 6 are nitrogen rich (WN) and 5 carbon rich (WC). Including the previously identified Blue, Yellow & Red Super& Hypergiants, Westerlund 1 clearly has a very rich po...
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