The Open UniversitySkip to content

The VLT-FLAMES Tarantula Survey XXIII. Two massive double-lined binaries in 30 Doradus

Howarth, I. D.; Dufton, P. L.; Dunstall, P. R.; Evans, C. J.; Almeida, L. A.; Bonanos, A. Z.; Clark, J. S.; Langer, N.; Sana, H.; Simón-Díaz, S.; Soszyński, I. and Taylor, W. D. (2015). The VLT-FLAMES Tarantula Survey XXIII. Two massive double-lined binaries in 30 Doradus. Astronomy & Astrophysics, 582, article no. A73.

Full text available as:
PDF (Version of Record) - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
Download (1MB) | Preview
DOI (Digital Object Identifier) Link:
Google Scholar: Look up in Google Scholar


Aims. We investigate the characteristics of two newly discovered short-period, double-lined, massive binary systems in the Large Magellanic Cloud, VFTS 450 (O9.7 II–Ib + O7::) and VFTS 652 (B1 Ib + O9: III:).

Methods. We perform model-atmosphere analyses to characterise the photospheric properties of both members of each binary (denoting the “primary” as the spectroscopically more conspicuous component). Radial velocities and optical photometry are used to estimate the binary-system parameters.

Results. We estimate Teff = 27 kK, log g = 2.9 (cgs) for the VFTS 450 primary spectrum (34 kK, 3.6: for the secondary spectrum); and Teff = 22 kK, log g = 2.8 for the VFTS 652 primary spectrum (35 kK, 3.7: for the secondary spectrum). Both primaries show surface nitrogen enrichments (of more than 1 dex for VFTS 652), and probable moderate oxygen depletions relative to reference LMC abundances. We determine orbital periods of 6.89 d and 8.59 d for VFTS 450 and VFTS 652, respectively, and argue that the primaries must be close to filling their Roche lobes. Supposing this to be the case, we estimate component masses in the range ∼20–50 M.

Conclusions. The secondary spectra are associated with the more massive components, suggesting that both systems are high-mass analogues of classical Algol systems, undergoing case-A mass transfer. Difficulties in reconciling the spectroscopic analyses with the light-curves and with evolutionary considerations suggest that the secondary spectra are contaminated by (or arise in) accretion disks.

Item Type: Journal Item
Copyright Holders: 2015 ESO
ISSN: 1432-0746
Keywords: binaries: eclipsing; binaries: close; binaries: spectroscopic
Academic Unit/School: Faculty of Science, Technology, Engineering and Mathematics (STEM) > Physical Sciences
Faculty of Science, Technology, Engineering and Mathematics (STEM)
Research Group: Astronomy
Related URLs:
Item ID: 53983
Depositing User: J. Simon Clark
Date Deposited: 28 Mar 2018 10:25
Last Modified: 08 Dec 2018 17:49
Share this page:


Altmetrics from Altmetric

Citations from Dimensions

Download history for this item

These details should be considered as only a guide to the number of downloads performed manually. Algorithmic methods have been applied in an attempt to remove automated downloads from the displayed statistics but no guarantee can be made as to the accuracy of the figures.

Actions (login may be required)

Policies | Disclaimer

© The Open University   contact the OU