ATMOSPHERE AND SPECTRAL MODELS OF THEKEPLER-FIELD PLANETS HAT-P-7b AND TrES-2

We develop atmosphere models of two of the three Kepler -field planets that were known prior to the start of the Kepler mission (HAT-P-7b and TrES-2). We find that published Kepler and Spitzer data for HAT-P-7b appear to require an extremely hot upper atmosphere on the dayside, with a strong thermal inversion and little day–night redistribution. The Spitzer data for TrES-2 suggest a mild thermal inversion with moderate day–night redistribution. We examine the effect of nonequilibrium chemistry on TrES-2 model atmospheres and find that methane levels must be adjusted by extreme amounts in order to cause even mild changes in atmospheric structure and emergent spectra. Our best-fit models to the Spitzer data for TrES-2 lead us to predict a low secondary eclipse planet–star flux ratio (≲2 × 10 −5 ) in the Kepler bandpass, which is consistent with what very recent observations have found. Finally, we consider how the Kepler -band optical flux from a hot exoplanet depends on the strength of a possible extra optical absorber in the upper atmosphere. We find that the optical flux is not monotonic in optical opacity, and the non-monotonicity is greater for brighter, hotter stars.