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Detection of additional Wolf-Rayet stars in the starburst cluster Westerlund 1 with SOAR

J. H. Groh·A. Damineli·M. Teodoro·C. L. Barbosa
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Abstract

We report the detection of 3 additional Wolf-Rayet stars in the young cluster Westerlund 1. They were selected as emission-line star candidates based on 1 micron narrow-band imaging of the cluster carried out at OPD/LNA (Brazil), and then confirmed as Wolf-Rayet stars by K-band spectroscopy performed at the 4.1 m SOAR telescope (Chile). Together with previous works, this increases the population of Wolf-Rayet stars detected in the cluster to 22 members. Moreover, it is presented for the first time a K-band spectrum of the luminous blue variable W243, which apparently implies in a higher temperature than that derived from optical spectra taken in 2003. The WC9 star WR-F was also observed, showing clear evidence of dust emission in the K-band.

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J. H. Groh, A. Damineli, M. Teodoro, C. L. Barbosa. 2006-06-20. Detection of additional Wolf-Rayet stars in the starburst cluster Westerlund 1 with SOAR. https://doi.org/10.1051/0004-6361%3A20064929

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