SuperWASP Observations of the Transiting Extrasolar planet XO-1b
  We report on observations of 11 transit events of the transiting extrasolar planet XO-1b by the SuperWASP-North observatory. From our data, obtained during May-September 2004, we find that the XO-1b orbital period is 3.941634 +/- 0.000137 days, the planetary radius is 1.34 +/- 0.12 Rjup and the inclination is 88.92 +/- 1.04 degrees, in good agreement with previously published values. We tabulate the transit timings from 2004 SuperWASP and XO data, which are the earliest obtained for XO-1b, and which will therefore be useful for future investigations of timing variations caused by additional perturbing planets. We also present an ephemeris for the transits. See http://www.superwasp.org for general project details. 
D. M. Wilson, B. Enoch, D. J. Christian, W. I. Clarkson, A. Collier   Cameron, H. J. Deeg, A. Evans, C. A. Haswell, C. Helli...