A Gas Giant Circumbinary Planet Transiting the F Star Primary of the Eclipsing Binary Star KIC 4862625 and the Independent Discovery and Characterization of the two transiting planets in the Kepler-47 System
We report the discovery of a transiting, gas giant circumbinary planet orbiting the eclipsing binary KIC 4862625 and describe our independent discovery of the two transiting planets orbiting Kepler-47 (Orosz et al. 2012). We describe a simple and semi-automated procedure for identifying individual transits in light curves and present our follow-up measurements of the two circumbinary systems. For the KIC 4862625 system, the 0.52+/-0.018 RJup radius planet revolves every ~138 days and occults the 1.47+/-0.08 MSun, 1.7 +/-0.06 RSun F8 IV primary star producing aperiodic transits of variable durations commensurate with the configuration of the eclipsing binary star. Our best-fit model indicates the orbit has a semi-major axis of 0.64 AU and is slightly eccentric, e=0.1. For the Kepler-47 system, we confirm the results of Orosz et al. (2012). Modulations in the radial velocity of KIC 4862625A are measured both spectroscopically and photometrically, i.e. via Doppler boosting, and produce similar results.