ABSTRACT. We present observations of a new low-mass, double-lined eclipsing binary system discovered using repeat observations of the celestial equator from the Sloan Digital Sky Survey II. Using near-infrared photometry and optical spectroscopy we have measured the properties of this short-period [P = 0.407037(14) days] system and its two components. We find the following parameters for the two components: M₁ = 0.272 ± 0.020 M, R₁ = 0.268 ± 0.010 R, M₂ = 0.240 ± 0.022 M, R₂ = 0.248 ± 0.0090 R, T₁ = 3320 ± 130 K, and T₂ = 3300 ± 130 K. The masses and radii of the two components of this system agree well with theoretical expectations based on models of low-mass stars, within the admittedly large errors. Future synoptic surveys like Pan-STARRS and LSST will produce a wealth of information about low-mass eclipsing systems and should make it possible, with an increased reliance on follow-up observations, to detect many systems with low-mass and substellar companions. With the large numbers of objects for which these surveys will produce high-quality photometry, we suggest that it becomes possible to identify such systems even with sparse time sampling and a relatively small number of individual observations.

Subject headings: binaries: eclipsing; stars: low-mass, brown dwarfs

Print publication: Issue 1 (2008 September 1)
Received 2007 June 26, accepted for publication 2008 April 21