Characterization of 9380 contact binaries from the CRTS Variable Sources Catalogue

Creators: Marsh, F. M.; Prince, T. A.; Mahabal, A. A.; Bellm, E. C.; Drake, A. J.; Djorgovski, S. G.

Abstract

We construct a sample of 9380 contact binaries (W UMa systems) by using the Catalina Real-Time Transient Survey Variables Sources Catalogue. By measuring brightness change rates, light-curve statistics, and temperatures for this sample, we improve the understanding of contact binary light-curve characteristics, and luminosity variability on decadal time-scales. We show that binaries with convective outer envelopes have a different distribution of light-curve amplitudes and magnitude differences between eclipse minima than binaries with radiative outer envelopes. We find that more than 2000 binaries exhibit a linear change in mean brightness over the 8-yr timespan of observations with at least 3σ significance. We note that 25.9 per cent of binaries with convective outer envelopes exhibit a significant change in brightness, while only 10.5 per cent of radiative binaries exhibit a significant change in brightness. In 205 binaries (2.2 per cent), we find that a sinusoid model better describes the luminosity trend within the 8-yr observation timespan. For these binaries, we report the amplitudes and periods (as estimated using observed half-periods) of this sinusoidal brightness variation and discuss possible mechanisms driving the variation.

Additional Information

© 2016 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. Accepted 2016 August 19. Received 2016 August 18; in original form 2016 June 20. This work made use of data products from the CSS survey. The CSS survey is funded by the National Aeronautics and Space Administration under Grant No. NNG05GF22G issued through the Science Mission Directorate Near-Earth Objects Observations Program. The CRTS survey is supported by the US National Science Foundation under grants AST-0909182, AST-1313422, AST-1413600, and AST-1518308. This work made use of data products from the SDSS-III survey. Funding for SDSS-III has been provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Science Foundation, and the US Department of Energy Office of Science. The SDSS-III web site is http://www.sdss3.org/. SDSS-III is managed by the Astrophysical Research Consortium for the Participating Institutions of the SDSS-III Collaboration including the University of Arizona, the Brazilian Participation Group, Brookhaven National Laboratory, Carnegie Mellon University, University of Florida, the French Participation Group, the German Participation Group, Harvard University, the Instituto de Astrofisica de Canarias, the Michigan State/Notre Dame/JINA Participation Group, Johns Hopkins University, Lawrence Berkeley National Laboratory, Max Planck Institute for Astrophysics, Max Planck Institute for Extraterrestrial Physics, New Mexico State University, New York University, Ohio State University, Pennsylvania State University, University of Portsmouth, Princeton University, the Spanish Participation Group, University of Tokyo, University of Utah, Vanderbilt University, University of Virginia, University of Washington, and Yale University. I would like to acknowledge the California Institute of Technology Summer Undergraduate Research Fellowship program for their financial support. I thank an anonymous reviewer for providing comments which greatly improved the paper. I thank James Davenport and Lynne Hillenbrand for their helpful comments, Jake VanderPlas for his help with gatspy, and John McBride for his help preparing the manuscript.

Attached Files

Published - stw2110.pdf

Supplemental Material - stw2110_Supp.zip

Files

stw2110.pdf

Files (4.5 MB)

Name	Size	Download all
stw2110.pdf md5:eedee57dc5cf31d09f065e7793a9ff00	3.6 MB	Preview Download
stw2110_Supp.zip md5:590a1f3d3bc886eebeca36b49be797b2	886.8 kB	Preview Download

Additional details

	All versions	This version
Views	0	0
Downloads	0	0
Data volume	0 Bytes	0 Bytes