Volume 584, December 2015
|Number of page(s)||19|
|Section||Galactic structure, stellar clusters and populations|
|Published online||13 November 2015|
2dF-AAOmega spectroscopy of massive stars in the Magellanic Clouds
1 UK Astronomy Technology Centre, Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ, UK
2 Astrophysics Group, School of Physical and Geographical Sciences, Lennard-Jones Laboratories, Keele University, ST5 5BG, UK
3 Institute for Physics and Astronomy, University of Potsdam, 14476 Potsdam, Germany
4 Astrophysics Research Institute, Liverpool John Moores University, Liverpool Science Park ic2, 146 Brownlow Hill, Liverpool L3 5RF, UK
Received: 13 February 2015
Accepted: 5 August 2015
We present spectral classifications from optical spectroscopy of 263 massive stars in the north-eastern region of the Large Magellanic Cloud. The observed two-degree field includes the massive 30 Doradus star-forming region, the environs of SN1987A, and a number of star-forming complexes to the south of 30 Dor. These are the first classifications for the majority (203) of the stars and include eleven double-lined spectroscopic binaries. The sample also includes the first examples of early OC-type spectra (AAΩ 30 Dor 248 and 280), distinguished by the weakness of their nitrogen spectra and by C IV λ4658 emission. We propose that these stars have relatively unprocessed CNO abundances compared to morphologically normal O-type stars, indicative of an earlier evolutionary phase. From analysis of observations obtained on two consecutive nights, we present radial-velocity estimates for 233 stars, finding one apparent single-lined binary and nine (>3σ) outliers compared to the systemic velocity; the latter objects could be runaway stars or large-amplitude binary systems and further spectroscopy is required to investigate their nature.
Key words: Magellanic Clouds / stars: early-type / stars: fundamental parameters / open clusters and associations: general
Tables 2–4 are available in electronic form at http://www.aanda.org
Copies of the spectra are only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (126.96.36.199) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/584/A5
© ESO, 2015
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.