PHOTOMETRICALLY DERIVED MASSES AND RADII OF THE PLANET AND STAR IN THE TrES-2 SYSTEM

We measure the mass and radius of the star and planet in the TrES-2 system using 2.7 years of observations by the Kepler spacecraft. The light curve shows evidence for ellipsoidal variations and Doppler beaming on a period consistent with the orbital period of the planet with amplitudes of 2.79(-0.62)(+0.44) and 3.44(-0.37)(+0.32) parts per million (ppm), respectively, and a difference between the dayside and the nightside planetary flux of 3.41(-0.82)(+0.55) ppm. We present an asteroseismic analysis of solar-like oscillations on TrES-2A which we use to calculate the stellar mass of 0.94 +/- 0.05 M-circle dot and radius of 0.95 +/- 0.02 R-circle dot. Using these stellar parameters, a transit model fit and the phase-curve variations, we determine the planetary radius of 1.162(-0.024)(+0.020) R-Jup and derive a mass for TrES-2b from the photometry of 1.44 +/- 0.21 M-Jup. The ratio of the ellipsoidal variation to the Doppler beaming amplitudes agrees to better than 2 sigma with theoretical predications, while our measured planet mass and radius agree within 2s of previously published values based on spectroscopic radial velocity measurements. We measure a geometric albedo of 0.0136(-0.0033)(+0.0022) and an occultation (secondary eclipse) depth of 6.5(-1.8)(+1.7) ppm which we combined with the day/night planetary flux ratio to model the atmosphere of TrES-2b. We find that an atmosphere model that contains a temperature inversion is strongly preferred. We hypothesize that the Kepler bandpass probes a significantly greater atmospheric depth on the night side relative to the day side.