Automated analysis of eclipsing binary light curves - II. Statistical analysis of OGLE LMC eclipsing binaries
Abstract
In the first paper of this series, we presented EBAS – Eclipsing Binary Automated Solver, a new fully automated algorithm to analyse the light curves of eclipsing binaries, based on the EBOP code. Here, we apply the new algorithm to the whole sample of 2580 binaries found in the Optical Gravitational Lensing Experiment (OGLE) Large Magellanic Cloud (LMC) photometric survey and derive the orbital elements for 1931 systems. To obtain the statistical properties of the short-period binaries of the LMC, we construct a well-defined subsample of 938 eclipsing binaries with main-sequence B-type primaries. Correcting for observational selection effects, we derive the distributions of the fractional radii of the two components and their sum, the brightness ratios and the periods of the short-period binaries. Somewhat surprisingly, the results are consistent with a flat distribution in log P between 2 and 10 d. We also estimate the total number of binaries in the LMC with the same characteristics, and not only the eclipsing binaries, to be about 5000. This figure leads us to suggest that (0.7 ± 0.4) per cent of the main-sequence B-type stars in the LMC are found in binaries with periods shorter than 10 d. This frequency is substantially smaller than the fraction of binaries found by small Galactic radial-velocity surveys of B stars. On the other hand, the binary frequency found by Hubble Space Telescope (HST) photometric searches within the late main-sequence stars of 47 Tuc is only slightly higher and still consistent with the frequency we deduced for the B stars in the LMC.
Additional Information
© 2006 The Authors. Journal compilation © 2006 RAS. In original form 2005 September 26. Received 2005 November 30. Accepted 2006 January 9. First published online April 21, 2006. We are grateful to the OGLE team, and to L. Wyrzykowski in particular, for the excellent photometric data set and the eclipsing binary analysis that was available to us. We thank J. Devor, G. Torres and I. Ribas for very useful comments. The remarks and suggestions of the referee, T. Zwitter, helped us to substantially improve the algorithm and this paper. This work was supported by the Israeli Science Foundation through grant no. 03/233.Attached Files
Published - MNRAS-2006-Mazeh-1531-42.pdf
Submitted - 0601201.pdf
Supplemental Material - mnras0367-1531-SD1.pdf
Supplemental Material - mnras0367-1531-SD2.pdf
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Additional details
- Eprint ID
- 71902
- Resolver ID
- CaltechAUTHORS:20161109-163450950
- 03/233
- Israel Science Foundation
- Created
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2016-11-17Created from EPrint's datestamp field
- Updated
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2021-11-11Created from EPrint's last_modified field