A search for planetary transits in open clusters

We report on the progress of a photometric search for planetary transits of stars in the open clusters NGC 6819, NGC 6940, and NGC 7789. The data were obtained during two allocations of ten nights with the Wide Field Camera on the Isaac Newton Telescope, La Palma, in mid-1999. These old, rich open clusters give numerous bright stars within the WFC field of view, allowing roughly 40 000 lower-main-sequence cluster stars to be monitored with comparable numbers of field stars. We have developed a semi-automated data-reduction pipeline to process the data and highlight potential transit candidates. We report the accuracy achieved in the photometry using a subset of the data and on factors affecting this accuracy, in addition to the variables found and the progress made in searching for transits.