The OB association LH 90 in the LMC : its age structure and Wolf-Rayet stars.
Abstract
We present new photometric and spectroscopic data of the stellar members of two tight clusters in the OB association LH 90 in the 30 Dor region. The α cluster contains an 09.7 and M 3 supergiant as well as two Wolf-Rayet stars of WN 6-7 and WC 4 subtype. We obtain an HR diagram of the whole association and find that it consists of at least two sub-populations: one with an age of 3-4 Myr and the other with an age of 7-8 Myr. The younger members are predominantly located in the western and central parts of the association. There are now seven confirmed Wolf- Rayet stars in the association. Their luminosities range from M_bol_~-7.9- -10.4 mag. We suggest that Brey 58 is an example of a Wolf- Rayet star which is in a post-red-supergiant phase. It appears that the stars in the a cluster are not coeval.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- December 1993
- Bibcode:
- 1993A&A...280..426T
- Keywords:
-
- B Stars;
- Magellanic Clouds;
- O Stars;
- Open Clusters;
- Star Distribution;
- Wolf-Rayet Stars;
- Astronomical Photometry;
- Astronomical Spectroscopy;
- Data Reduction;
- Hertzsprung-Russell Diagram;
- Spectrophotometers;
- Spectrum Analysis;
- Astronomy