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We report the discovery of WTS-2 b, a typical hot Jupiter in an unusually close 1.02-day orbit to a K-dwarf star. This is the second planet to be discovered in the infrared light curves of the WFCAM Transit Survey (WTS) and is only one-and-a-half times the separation from its host star at which is would be destroyed by Roche lobe overflow. The predicted remaining lifetime of the planet is just 38 Myrs, assuming a tidal dissipation quality factor ofQ'* = 106. The magnitude ofQ'* is largely unconstrained by observations, thus WTS-2 b provides a useful calibration point for theories describing how frictional processes within a host star affect the tidal orbital evolution of its companion giant planets. It is expected that stars with large convective envelopes are more efficient at dissipating the orbital energy of the planet, and WTS-2 b provides an observational constraint in the sparsely populated K-dwarf regime. In addition, despite its relatively faint magnitude, the favourable size ratio of the WTS-2 star-planet system and the predicted hot equilibrium temperature of the planet will make it possible to characterise the planet's atmosphere via secondary eclipse measurements using existing ground-based instrumentation. [ABSTRACT FROM AUTHOR]

We present an analysis of the photometric variability ofMdwarfs in theWFCAM Transit Survey, selected from spectral types inferred by their WTS and SDSS colours, with periods detected using a Lomb-Scargle Periodogram Analisys. We estimate population membership of these objects from their tangential velocities and photometric parralaxes. Examples of M dwarfs with variable light curve morphologuies are found. We discuss possible causes for this and make use of models of spotted stars in our interpretation of the results. [ABSTRACT FROM AUTHOR]

The Wide Field Camera Transit Survey is a pioneer program aimed to search for extra-solar planets in the near-infrared. The standard data reduction pipeline of the program uses aperture photometry to construct the light curves. We alternatively apply the difference imaging method for the most complete field in the survey and carry out a quantitative comparison between the photometric precision of both methods. We also report an implementation on the box-fitting detection algorithm, which performs a trapezoid-fit to the folded light curve. Subsequently we apply a set of selection criteria to the light curves to search for transit candidates, incorporating a parameter to characterize the shape of the transit. We carry out a detailed analysis of 11 candidates and provide a classification scheme to separate binary from planet candidates. Furthermore we report the detection of five faint extremely-short period eclipsing binary systems with periods shorter than 0.23 days and one candidate M-dwarf/M-dwarf eclipsing binary. [ABSTRACT FROM AUTHOR]

We report the discovery of WTS1 b, the first extrasolar planet found by the WFCAM Transit Survey. For one of the most promising transiting candidates, high-resolution spectra taken at the Hobby- Eberly Telescope (HET) allowed us to estimate the spectroscopic parameters of the host star, a late-F main sequence dwarf (V = 16.13), and to measure its radial velocity variations. The combined analysis of the light curves and spectroscopic data resulted in an orbital period of the companion of 3.35 days, a planetary mass of 4.01 ± 0.35MJ, and a planetary radius of 1.49-0.18+0.16 RJ . WTS1 b has one of the largest radius anomalies among the known hot Jupiters in the mass range 3-5MJ. [ABSTRACT FROM AUTHOR]