A Survey for Planetary Transits in the Field of NGC 7789
astro-ph
/ Authors
D. M. Bramich, Keith Horne, I. A. Bond, R. A. Street, A. Collier Cameron, B. Hood, J. Cooke, D. James, T. A. Lister, D. Mitchell
and 5 more authors
K. Pearson, A. Penny, A. Quirrenbach, N. Safizadeh, Y. Tsapras
/ Abstract
We present results from 30 nights of observations of the open cluster NGC 7789 with the WFC camera on the INT telescope in La Palma. From ~900 epochs, we obtained lightcurves and Sloan r-i colours for ~33000 stars, with ~2400 stars with better than 1% precision. We expected to detect ~2 transiting hot Jupiter planets if 1% of stars host such a companion and that a typical hot Jupiter radius is ~1.2RJ. We find 24 transit candidates, 14 of which we can assign a period. We rule out the transiting planet model for 21 of these candidates using various robust arguments. For 2 candidates we are unable to decide on their nature, although it seems most likely that they are eclipsing binaries as well. We have one candidate exhibiting a single eclipse for which we derive a radius of 1.81+0.09-0.00RJ. Three candidates remain that require follow-up observations in order to determine their nature.