Exoplanet Atmospheric Refraction Effects in the Kepler Sample

Dereck Lizotte ( Université de Montréal )

We present a detailed analysis regarding the viability of detection of refraction effects in exoplanet atmospheres in the Kepler/CKS sample using binning techniques for the Kepler light curves and comparing them with simulated refraction effects. We split the Kepler/CKS planet into sub-populations according to the Period-Radius valley, applying the feasibility of detection of refraction effects towards measuring their sensitivity with regards to planetary and atmospheric properties. Specifically, we test whether planets above the Period-Radius valley have H/He atmospheres, which would then be possibly evaporated by high radiation from stellar activity, leaving rocky cores (below the valley). It is shown that optically thin, H/He dominated atmospheres are not common in the observed planetary population, very likely owing to their small orbital period. This would cause the planets to have hotter atmospheres susceptible to strong opacity sources, effectively removing or reducing any potential refraction effects.