Poster abstract

Double-lined eclipsing binary systems (EBs) provide the most accurate way to measure fundamental properties, such as the mass and radius, of very low-mass stars and brown dwarfs (BDs). We present here the WFCAM Transit Survey (WTS); an ambitious, near-IR photometric monitoring campaign of ~6000 M-dwarfs across four 1.5 sq deg fields situated >5 degrees above and below the galactic plane. We utilise a unique opportunity provided by the highly efficient queue-scheduled operational mode of the UKIRT to observe our fields, with at least one visible at any time, when atmospheric conditions and RA coverage are unsuitable for other ongoing UKIRT programs. By probing the peak of the M-dwarf spectral energy distribution (13 < J < 17), we obtain a statistically significant sample of low-mass stars, which allows us to place meaningful constraints on the occurrence and formation of substellar objects around M-dwarfs. In addition, we can accurately measure the distribution of their masses, radii, mass ratios and separations. The WTS has achieved one thousand epochs after 2 years in one of our target fields and will continue until April 2012. We are probing orbital periods between 0.1-10 days. Our light curves have a per data point photometric precision of ~3-4 mmag for the brightest objects, with RMS scatter < 1% for J < 16, which is amply sufficient to detect BDs and can even reveal Earth-size companions around M-dwarfs. I report here on the goals of our survey, our most recent low-mass EBs results and the properties of our M-dwarf target sample. I also discuss our processing methods and how we combat the challenges encountered when observing occultations of faint red stars and the spectroscopic follow-up required to confirm them.